The Human Brain During the Third Trimester

The HUMAN BRAIN during the THIRD TRIMESTER ATLAS OF HUMAN CENTRAL NERVOUS SYSTEM DEVELOPMENT SERIES Shirley A. Bayer...

Author: Shirley A. Bayer | Joseph Altman

93 downloads 1142 Views 117MB Size Report

This content was uploaded by our users and we assume good faith they have the permission to share this book. If you own the copyright to this book and it is wrongfully on our website, we offer a simple DMCA procedure to remove your content from our site. Start by pressing the button below!
Report copyright / DMCA form

DOWNLOAD PDF

The

HUMAN BRAIN during the THIRD TRIMESTER

ATLAS OF HUMAN CENTRAL NERVOUS SYSTEM DEVELOPMENT SERIES Shirley A. Bayer and Joseph Altman

VOLUME 1 The Spinal Cord from Gestational Week 4 to the 4th Postnatal Month

VOLUME 2 The Human Brain during the Third Trimester

VOLUME 3 The Human Brain during the Second Trimester

VOLUME 4 The Human Brain during the Late First Trimester

VOLUME 5 The Human Brain during the Early First Trimester

The

HUMAN BRAIN during the THIRD TRIMESTER Shirley A. Bayer and Joseph Altman

CRC PR E S S Boca Raton London New York Washington, D.C.

Library of Congress Cataloging-in-Publication Data Catalog record is available from the Library of Congress under LCCN: 2003065455 This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microÞlming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publisher. The consent of CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. SpeciÞc permission must be obtained in writing from CRC Press LLC for such copying. Direct all inquiries to CRC Press LLC, 2000 N.W. Corporate Blvd., Boca Raton, Florida 33431. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identiÞcation and explanation, without intent to infringe.

Visit the CRC Press Web site at www.crcpress.com © 2004 by CRC Press LLC No claim to original U.S. Government works International Standard Book Number 0-8493-1421-6 Library of Congress Card Number Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Printed on acid-free paper

DEDICATION We dedicate this volume to the memory of Dr. Paul Ivan Yakovlev (1894-1983) who spent 42 years (1930-1972) of his productive life in assembling and processing more than 1000 normal and pathological human brain specimens that now constitute the precious Yakovlev Collection.

ACKNOWLEDGMENTS We thank Dr. William DeMyer, pediatric neurologist at Riley Hospital for Children, Indiana University Medical Center, Indianapolis, Indiana, for access to his personal library on human central nervous system development. We also thank the staff of the National Museum of Health and Medicine at the Armed Forces Institute of Pathology, Walter Reed Hospital, Washington, D.C.: Dr. Adrianne Noe, Director; Archibald J. Fobbs, Curator of the Yakovlev Collection; Elizabeth C. Lockett, and William Discher. We are most grateful to Dr. James M. Petras at the Walter Reed Institute of Research who made his dark room facilities available so that we could develop all the photomicrographs on location rather than in our laboratory in Indiana. Finally, we thank Barbara Norwitz, Erika Dery, Samar Haddad, Shayna Murry, and Jonathan Pennell at CRC Press for their personal attention to us and for expert help during production of the manuscript.

CONTENTS PART I. INTRODUCTION --------------------------------------------------------------------- 1 A. Organization of the Atlas --------------------------------------------------------- 1 B. Specimens Used --------------------------------------------------------------------- 1 C. Photography and Computer Processing -------------------------------------- 1 D. Identification of Brain Structures ---------------------------------------------- 2 E. References --------------------------------------------------------------------------- 3

High Magnification Plates 42A, 42B: (Level 16: Section 1221) ------------ 58, 59 High Magnification Plates 43A, 43B: (Level 17: Section 1311) ------------ 60, 61 High Magnification Plates 44A, 44B: (Level 18: Section 1371) ------------ 62, 63 High Magnification Plates 45A, 45B: (Level 19: Section 1501) ------------ 64, 65 High Magnification Plates 46A, 46B: (Levels 20, 21: Sections 1611, 1711) ------------------------------------------- 66, 67

PART II. GW37 CORONAL --------------------------------------------------------------------- 4 Low Magnification Plate 1 (Level 1: Section 161) ---------------------------------- 6 Low Magnification Plate 2 (Level 2: Section 281) ---------------------------------- 7 Low Magnification Plate 3 (Level 3: Section 361) ---------------------------------- 8 Low Magnification Plate 4 (Level 4: Section 511) ---------------------------------- 9 Low Magnification Plate 5 (Level 5: Section 611) -------------------------------- 10 Low Magnification Plate 6 (Level 6: Section 691) -------------------------------- 11 Low Magnification Plate 7 (Level 7: Section 721) -------------------------------- 12 Low Magnification Plate 8 (Level 8: Section 761) -------------------------------- 13 Low Magnification Plate 9 (Level 9: Section 831) -------------------------------- 14 Low Magnification Plate 10 (Level 10: Section 881) ----------------------------- 15 Low Magnification Plate 11 (Level 11: Section 981) ----------------------------- 16 Low Magnification Plate 12 (Level 12: Section 1021) --------------------------- 17 Low Magnification Plate 13 (Level 13: Section 1081) --------------------------- 18 Low Magnification Plate 14 (Level 14: Section 1141) --------------------------- 19 Low Magnification Plate 15 (Level 15: Section 1181) --------------------------- 20 Low Magnification Plate 16 (Level 16: Section 1221) --------------------------- 21 Low Magnification Plate 17 (Level 17: Section 1311) --------------------------- 22 Low Magnification Plate 18 (Level 18: Section 1371) --------------------------- 23 Low Magnification Plate 19 (Level 19: Section 1501) --------------------------- 24 Low Magnification Plate 20 (Levels 20, 21: Sections 1611, 1711) ------------- 25 High Magnification Cortex Plate 21: Frontal Cortex ----------------------------- 26 High Magnification Cortex Plate 22: Frontal Cortex ----------------------------- 27 High Magnification Cortex Plate 23: Precentral Gyrus --------------------------- 28 High Magnification Cortex Plate 24: Precentral Gyrus --------------------------- 29 High Magnification Cortex Plate 25: Postcentral Gyrus ------------------------- 30 High Magnification Cortex Plate 26: Postcentral Gyrus ------------------------- 31 High Magnification Cortex Plate 27: Parietal Cortex ----------------------------- 32 High Magnification Cortex Plate 28: Parietal Cortex ----------------------------- 33 High Magnification Cortex Plate 29: Striate/Peristriate Cortical Transition Area ----------------------------------------- 34 High Magnification Cortex Plate 30: Striate/Peristriate Cortical Transition Area ----------------------------------------- 35 High Magnification Plates 31A, 31B: (Level 5: Section 611) --------------- 36, 37 High Magnification Plates 32A, 32B: (Level 6: Section 691) --------------- 38, 39 High Magnification Plates 33A, 33B: (Level 7: Section 721) --------------- 40, 41 High Magnification Plates 34A, 34B: (Level 8: Section 761) --------------- 42, 43 High Magnification Plates 35A, 35B: (Level 9: Section 831) --------------- 44, 45 High Magnification Plates 36A, 36B: (Level 10: Section 881) -------------- 46, 47 High Magnification Plates 37A, 37B: (Level 11: Section 981) -------------- 48, 49 High Magnification Plates 38A, 38B: (Level 12: Section 1021) ------------ 50, 51 High Magnification Plates 39A, 39B: (Level 13: Section 1081) ------------ 52, 53 High Magnification Plates 40A, 40B: (Level 14: Section 1141) ------------ 54, 55 High Magnification Plates 41A, 41B: (Level 15: Section 1181) ------------ 56, 57

PART III. GW37 SAGITTAL ------------------------------------------------------------------- 68 Low Magnification Plate 47 (Level 1: Section 961) ------------------------------ 70 Low Magnification Plate 48 (Level 2: Section 941) ------------------------------ 71 Low Magnification Plate 49 (Level 3: Section 841) ------------------------------ 72 Low Magnification Plate 50 (Level 4: Section 781) ------------------------------ 73 Low Magnification Plate 51 (Level 5: Section 721) ------------------------------ 74 Low Magnification Plate 52 (Level 6: Section 661) ------------------------------ 75 Low Magnification Plate 53 (Level 7: Section 621) ------------------------------ 76 Low Magnification Plate 54 (Level 8: Section 501) ------------------------------ 77 High Magnification Plates 55A, 55B: (Level 1: Section 961) --------------- 78, 79 High Magnification Plates 56A, 56B: (Level 2: Section 941) --------------- 80, 81 High Magnification Plates 57A, 57B: (Level 3: Section 841) --------------- 82, 83 High Magnification Plates 58A, 58B: (Level 4: Section 781) --------------- 84, 85 High Magnification Plates 59A, 59B: (Level 5: Section 721) --------------- 86, 87 High Magnification Plates 60A, 60B: (Level 6: Section 661) --------------- 88, 89 High Magnification Plates 61A, 61B: (Level 7: Section 621) --------------- 90, 91 High Magnification Plates 62A, 62B: (Level 8: Section 501) --------------- 92, 93 High Magnification Cerebellum Plate 63: Nodulus ------------------------------- 94 High Magnification Cerebellum Plate 64: Paramedian Lobule ------------------ 95 PART IV. GW37 HORIZONTAL -------------------------------------------------------------- 96 Low Magnification Plate 65 (Level 1: Section 341) ------------------------------ 98 Low Magnification Plate 66 (Level 2: Section 441) ------------------------------ 99 Low Magnification Plate 67 (Level 3: Section 531) ----------------------------- 100 Low Magnification Plate 68 (Level 4: Section 561) ----------------------------- 101 Low Magnification Plate 69 (Level 5: Section 631) ----------------------------- 102 Low Magnification Plate 70 (Level 6: Section 731) ----------------------------- 103 Low Magnification Plate 71 (Level 7: Section 761) ----------------------------- 104 Low Magnification Plate 72 (Level 8: Section 801) ----------------------------- 105 Low Magnification Plate 73 (Level 9: Section 851) ----------------------------- 106 Low Magnification Plate 74 (Level 10: Section 921) ---------------------------- 107 Low Magnification Plate 75 (Level 11: Section 981) ---------------------------- 108 Low Magnification Plate 76 (Level 12: Section 1051) -------------------------- 109 Low Magnification Plate 77 (Level 13: Section 1111) -------------------------- 110 Low Magnification Plate 78 (Level 14: Section 1161) -------------------------- 111 Low Magnification Plate 79 (Levels 15, 16: Sections 1251, 1311) ------------ 112 Low Magnification Plate 80 (Levels 17, 18, 19: Sections 1331, 1381, 1441) ---------------------------------- 113 High Magnification Plates 81A, 81B: (Level 3: Section 531) ------------ 114, 115 High Magnification Plates 82A, 82B: (Level 4: Section 561) ------------ 116, 117 High Magnification Plates 83A, 83B: (Level 5: Section 631) ------------ 118, 119 High Magnification Plates 84A, 84B: (Level 6: Section 731) ------------ 120, 121 High Magnification Plates 85A, 85B: (Level 7: Section 761) ------------ 122, 123 High Magnification Plates 86A, 86B: (Level 8: Section 801) ------------ 124, 125

CONTENTS High Magnification Plates 87A, 87B: (Level 9: Section 851) ------------ 126, 127 High Magnification Plates 88A, 88B: (Level 10: Section 921) ----------- 128, 129 High Magnification Plates 89A, 89B: (Level 11: Section 981) ----------- 130, 131 High Magnification Plates 90A, 90B: (Level 12: Section 1051) --------- 132, 133 High Magnification Plates 91A, 91B: (Level 13: Section 1111) --------- 134, 135 High Magnification Plates 92A, 92B: (Level 14: Section 1161) --------- 136, 137 High Magnification Plates 93A, 93B: (Level 15: Section 1251) --------- 138, 139 High Magnification Plates 94A, 94B: (Levels 16, 17: Sections 1311, 1331) ---------------------------------------- 140, 141 High Magnification Plates 95A, 95B: (Levels 18, 19: Sections 1381, 1441) ---------------------------------------- 142, 143 PART V. GW32 SAGITTAL ------------------------------------------------------------------ 144 Low Magnification Plate 96 (Level 1: Section 801) ----------------------------- 146 Low Magnification Plate 97 (Level 2: Section 741) ----------------------------- 147 Low Magnification Plate 98 (Level 3: Section 681) ----------------------------- 148 Low Magnification Plate 99 (Level 4: Section 581) ----------------------------- 149 Low Magnification Plate 100 (Level 5: Section 481) ---------------------------- 150 Low Magnification Plate 101 (Level 6: Section 421) ---------------------------- 151 High Magnification Plates 102A, 102B: (Level 1: Section 801) --------- 152, 153 High Magnification Plates 103A, 103B: (Level 2: Section 741) --------- 154, 155 High Magnification Plates 104A, 104B: (Level 3: Section 681) --------- 156, 157 High Magnification Plates 105A, 105B: (Level 4: Section 581) --------- 158, 159 High Magnification Plates 106A, 106B: (Level 5: Section 481) --------- 160, 161 High Magnification Plates 107A, 107B: (Level 6: Section 421) --------- 162, 163 High Magnification Cerebellum Plate 108: Culmen, Lingula ------------------ 164 High Magnification Cerebellum Plate 109: Folium ------------------------------ 165 High Magnification Cerebellum Plate 110: Uvula, Nodulus ------------------- 166 High Magnification Cerebellum Plate 111: Germinal Trigone ----------------- 167 PART VI. GW30 HORIZONTAL ------------------------------------------------------------- 168 Low Magnification Plate 112 (Level 1: Section 261) ---------------------------- 170 Low Magnification Plate 113 (Level 2: Section 400) ---------------------------- 171 Low Magnification Plate 114 (Level 3: Section 441) ---------------------------- 172 Low Magnification Plate 115 (Level 4: Section 521) ---------------------------- 173 Low Magnification Plate 116 (Level 5: Section 621) ---------------------------- 174 Low Magnification Plate 117 (Level 6: Section 671) ---------------------------- 175 Low Magnification Plate 118 (Level 7: Section 701) ---------------------------- 176 Low Magnification Plate 119 (Level 8: Section 721) ---------------------------- 177 Low Magnification Plate 120 (Level 9: Section 761) ---------------------------- 178 Low Magnification Plate 121 (Level 10: Section 801) -------------------------- 179 Low Magnification Plate 122 (Level 11: Section 841) -------------------------- 180 Low Magnification Plate 123 (Level 12: Section 861) -------------------------- 181 Low Magnification Plate 124 (Level 13: Section 881) -------------------------- 182 Low Magnification Plate 125 (Level 14: Section 941) -------------------------- 183 Low Magnification Plate 126 (Level 15: Section 1001) ------------------------- 184 Low Magnification Plate 127 (Level 16: Section 1041) ------------------------- 185 Low Magnification Plate 128 (Levels 17, 18: Sections 1081, 1121) ---------- 186 Low Magnification Plate 129 (Levels 19, 20: Sections 1161, 1201) ---------- 187 Low Magnification Plate 130 (Levels 21, 22: Sections 1241, 1281) ---------- 188 Low Magnification Plate 131 (Levels 23, 24: Sections 1351, 1391) ---------- 189

High Magnification Plates 132A, 132B: (Level 3: Section 441) --------- 190, 191 High Magnification Plates 133A, 133B: (Level 4: Section 521) --------- 192, 193 High Magnification Plates 134A, 134B: (Level 5: Section 621) --------- 194, 195 High Magnification Plates 135A, 135B: (Level 6: Section 671) --------- 196, 197 High Magnification Plates 136A, 136B: (Level 7: Section 701) --------- 198, 199 High Magnification Plates 137A, 137B: (Level 8: Section 721) --------- 200, 201 High Magnification Plates 138A, 138B: (Level 9: Section 761) --------- 202, 203 High Magnification Plates 139A, 139B: (Level 10: Section 801) -------- 204, 205 High Magnification Plates 140A, 140B: (Level 11: Section 841) -------- 206, 207 High Magnification Plates 141A, 141B: (Level 12: Section 861) -------- 208, 209 High Magnification Plates 142A, 142B: (Level 13: Section 881) -------- 210, 211 High Magnification Plates 143A, 143B: (Level 14: Section 941) -------- 212, 213 High Magnification Plates 144A, 144B: (Level 15: Section 1001) ------ 214, 215 High Magnification Plates 145A, 145B: (Level 16: Section 1041) ------ 216, 217 High Magnification Plates 146A, 146B: (Level 17: Section 1081) ------ 218, 219 High Magnification Plates 147A, 147B: (Level 18: Section 1121) ------ 220, 221 High Magnification Plates 148A, 148B: (Level 19: Section 1161) ------ 222, 223 High Magnification Plates 149A, 149B: (Levels 20, 21: Sections 1201, 1241) ---------------------------------------- 224, 225 High Magnification Plates 150A, 150B: (Levels 22, 23, 24: Sections 1281, 1351, 1391) ---------------------------- 226, 227 PART VII. GW29 CORONAL ------------------------------------------------------------------ 228 Low Magnification Plate 151 (Level 1: Section 321) ---------------------------- 230 Low Magnification Plate 152 (Level 2: Section 501) ---------------------------- 231 Low Magnification Plate 153 (Level 3: Section 621) ---------------------------- 232 Low Magnification Plate 154 (Level 4: Section 701) ---------------------------- 233 Low Magnification Plate 155 (Level 5: Section 741) ---------------------------- 234 Low Magnification Plate 156 (Level 6: Section 781) ---------------------------- 235 Low Magnification Plate 157 (Level 7: Section 821) ---------------------------- 236 Low Magnification Plate 158 (Level 8: Section 861) ---------------------------- 237 Low Magnification Plate 159 (Level 9: Section 901) ---------------------------- 238 Low Magnification Plate 160 (Level 10: Section 981) -------------------------- 239 Low Magnification Plate 161 (Level 11: Section 1021) ------------------------- 240 Low Magnification Plate 162 (Level 12: Section 1061) ------------------------- 241 Low Magnification Plate 163 (Level 13: Section 1101) ------------------------- 242 Low Magnification Plate 164 (Level 14: Section 1161) ------------------------- 243 Low Magnification Plate 165 (Level 15: Section 1201) ------------------------- 244 Low Magnification Plate 166 (Level 16: Section 1261) ------------------------- 245 Low Magnification Plate 167 (Level 17: Section 1301) ------------------------- 246 Low Magnification Plate 168 (Level 18: Section 1361) ------------------------- 247 Low Magnification Plate 169 (Level 19: Section 1521) ------------------------- 248 Low Magnification Plate 170 (Level 20: Section 1621) ------------------------- 249 High Magnification Cortex Plate 171: Frontal Cortex --------------------------- 250 High Magnification Cortex Plate 172: Precentral Gyrus ------------------------ 251 High Magnification Cortex Plate 173: Parietal Cortex -------------------------- 252 High Magnification Cortex Plate 174: Striate Cortex ---------------------------- 253 High Magnification Plates 175A, 175B: (Level 4: Section 701) --------- 254, 255 High Magnification Plates 176A, 176B: (Level 5: Section 741) --------- 256, 257 High Magnification Plates 177A, 177B: (Level 6: Section 781) --------- 258, 259 High Magnification Plates 178A, 178B: (Level 7: Section 821) --------- 260, 261

CONTENTS High Magnification Plates 179A, 179B: (Level 8: Section 861) --------- 262, 263 High Magnification Plates 180A, 180B: (Level 9: Section 901) --------- 264, 265 High Magnification Plates 181A, 181B: (Level 10: Section 981) -------- 266, 267 High Magnification Plates 182A, 182B: (Level 11: Section 1021) ------ 268, 269 High Magnification Plates 183A, 183B: (Level 12: Section 1061) ------ 270, 271 High Magnification Plates 184A, 184B: (Level 13: Section 1101) ------ 272, 273 High Magnification Plates 185A, 185B: (Level 14: Section 1161) ------ 274, 275 High Magnification Plates 186A, 186B: (Level 15: Section 1201) ------ 276, 277 High Magnification Plates 187A, 187B: (Level 16: Section 1261) ------ 278, 279 High Magnification Plates 188A, 188B: (Level 17: Section 1301) ------ 280, 281 High Magnification Plates 189A, 189B: (Level 18: Section 1361) ------ 282, 283 PART VIII. GW26 SAGITTAL ------------------------------------------------------------------ 284 Low Magnification Plate 190 (Level 1: Section 501) ---------------------------- 286 Low Magnification Plate 191 (Level 2: Section 481) ---------------------------- 287 Low Magnification Plate 192 (Level 3: Section 461) ---------------------------- 288 Low Magnification Plate 193 (Level 4: Section 421) ---------------------------- 289 Low Magnification Plate 194 (Level 5: Section 381) ---------------------------- 290 Low Magnification Plate 195 (Level 6: Section 361) ---------------------------- 291 Low Magnification Plate 196 (Level 7: Section 341) ---------------------------- 292 Low Magnification Plate 197 (Level 8: Section 321) ---------------------------- 293 Low Magnification Plate 198 (Level 9: Section 261) ---------------------------- 294 Low Magnification Plate 199 (Level 10: Section 221) -------------------------- 295 High Magnification Plates 200A, 200B: (Level 1: Section 501) --------- 296, 297 High Magnification Plates 201A, 201B: (Level 2: Section 481) --------- 298, 299 High Magnification Plates 202A, 202B: (Level 3: Section 461) --------- 300, 301 High Magnification Plates 203A, 203B: (Level 4: Section 421) --------- 302, 303 High Magnification Plates 204A, 204B: (Level 5: Section 381) --------- 304, 305 High Magnification Plates 205A, 205B: (Level 6: Section 361) --------- 306, 307 High Magnification Plates 206A, 206B: (Level 7: Section 341) --------- 308, 309 High Magnification Plates 207A, 207B: (Level 8: Section 321) --------- 310, 311 High Magnification Plates 208A, 208B: (Level 9: Section 261) --------- 312, 313 High Magnification Plates 209A, 209B: (Level 10: Section 221) -------- 314, 315 High Magnification Cerebellum Plate 210: Lingula ----------------------------- 316 High Magnification Cerebellum Plate 211: Culmen ----------------------------- 317 High Magnification Cerebellum Plate 212: Declive ----------------------------- 318 High Magnification Cerebellum Plate 213: Uvula ------------------------------- 319

High Magnification Cerebellum Plate 214: Nodulus ---------------------------- 320 High Magnification Cerebellum Plate 215: Germinal Trigone ----------------- 321 PART IX. GW26 HORIZONTAL ------------------------------------------------------------- 322 Low Magnification Plate 216 (Level 1: Section 240) ---------------------------- 324 Low Magnification Plate 217 (Level 2: Section 340) ---------------------------- 325 Low Magnification Plate 218 (Level 3: Section 400) ---------------------------- 326 Low Magnification Plate 219 (Level 4: Section 460) ---------------------------- 327 Low Magnification Plate 220 (Level 5: Section 520) ---------------------------- 328 Low Magnification Plate 221 (Level 6: Section 560) ---------------------------- 329 Low Magnification Plate 222 (Level 7: Section 620) ---------------------------- 330 Low Magnification Plate 223 (Level 8: Section 660) ---------------------------- 331 Low Magnification Plate 224 (Level 9: Section 700) ---------------------------- 332 Low Magnification Plate 225 (Level 10: Section 740) -------------------------- 333 Low Magnification Plate 226 (Level 11: Section 780) -------------------------- 334 Low Magnification Plate 227 (Level 12: Section 820) -------------------------- 335 Low Magnification Plate 228 (Levels 13, 14: Sections 860, 880) ------------------------------------------------- 336 Low Magnification Plate 229 (Levels 15, 16, 17: Sections 900, 940, 960) --------------------------------------- 337 High Magnification Plates 230A, 230B: (Level 3: Section 400) --------- 338, 339 High Magnification Plates 231A, 231B: (Level 4: Section 460) --------- 340, 341 High Magnification Plates 232A, 232B: (Level 5: Section 520) --------- 342, 343 High Magnification Plates 233A, 233B: (Level 6: Section 560) --------- 344, 345 High Magnification Plates 234A, 234B: (Level 7: Section 620) --------- 346, 347 High Magnification Plates 235A, 235B: (Level 8: Section 660) --------- 348, 349 High Magnification Plates 236A, 236B: (Level 9: Section 700) --------- 350, 351 High Magnification Plates 237A, 237B: (Level 10: Section 740) -------- 352, 353 High Magnification Plates 238A, 238B: (Level 11: Section 780) -------- 354, 355 High Magnification Plates 239A, 239B: (Level 12: Section 820) -------- 356, 357 High Magnification Plates 240A, 240B: (Level 13: Section 860) -------- 358, 359 High Magnification Plates 241A, 241B: (Level 14: Section 880) -------- 360, 361 High Magnification Plates 242A, 242B: (Level 15: Section 900) -------- 362, 363 High Magnification Plates 243A, 243B: (Level 16: Section 940) -------- 364, 365 High Magnification Plates 244A, 244B: (Level 17: Section 960) -------- 366, 367 GLOSSARY

------------------------------------------------------------------------------------------ 368

1

PART PART I: I:

INTRODUCTION INTRODUCTION A. Organization of the Atlas This Atlas focuses on the development of the human brain during the third trimester, and is Volume 2 in the Atlas of Human Central Nervous System Development series. Volume 1 (Bayer and Altman, 2002) provides a record of the development of the spinal cord. The brain specimens presented here are nearing anatomical maturity (at the light microscopic level) and nearly all the structures present in the adult brain are recognizable. Our rationale for starting our brain studies with the most mature specimens is to begin with the known (this volume), then gradually proceed to the unknown – the uncharted territory of human brain development during the midfetal and early embryonic periods (Volumes 3, 4 and 5). The journey will provide a record of when and how known brain structures differentiate, when they first become recognizable, and when they are still absent in less mature specimens. By the third trimester, as seen in the late-fetal specimens illustrated in this volume, only remnants of the embryonic nervous system – the primary neuroepithelium, the secondary germinal matrices, the streams of migrating neurons, and the transitional brain areas – remain. These embryonic structures gradually become more prominent in the younger fetuses to be dealt with in the forthcoming volumes, and are the sole components of the brain in the youngest embryos. This volume contains grayscale photographs of Nissl-stained sections of brains cut in three cardinal planes (coronal, sagittal, and horizontal) of normal specimens from gestational week (GW) 37 in the late third trimester to GW26 in the early third trimester. In this, and in the forthcoming volumes, older specimens precede younger specimens. Virtually every named brain structure is shown in at least one plane, and most structures can be discerned in two or three planes from specimens of the same nominal age or closely matched ages. Hence, this volume provides a comprehensive atlas of the maturing brain as well as of its late-stage development. In this volume, each specimen is presented in a separate part of the Atlas: GW37 in the coronal plane in Part II; GW37 in the sagittal plane in Part III; GW37 in the horizontal plane in Part IV;

GW32 in the sagittal plane in Part V; GW30 in the horizontal plane in Part VI; GW29 in the coronal plane in Part VII; GW26 in the sagittal plane in Part VIII; and GW26 in the horizontal plane in Part IX. Selected coronal plates are presented in order from rostral to caudal; the dorsal part of each section is always toward the top of the page, the ventral part at the bottom, and the midline is in the vertical center of each section. Sagittal plates are ordered from medial to lateral; the anterior part of each section is always facing to the left, posterior to the right. Horizontal plates are ordered from dorsal to ventral; the anterior part of each section is always facing to the left, posterior to the right, and the midline is in the horizontal center of each section. Each Part contains low magnification plates and high magnification companion plates. The low magnification plates appear on single pages that show unlabeled full contrast photos of entire sections on the left side and low contrast copies on the right with superimposed outlines and unabbreviated labels. The main purpose of the low magnification plates is to identify the large structures of the brain, such as the various lobes and gyri of the cerebral cortex, and large subdivisions of the brain core, such as the basal ganglia, thalamus, hypothalamus, midbrain, pons, cerebellum, and medulla. The high magnification companion plates are designated as A and B on facing pages and feature enlarged views of the brain core. The A part of each plate on the left page shows the full contrast photograph without labels; the B part shows low contrast copies of the same photograph on the right page with superimposed outlines of structures and unabbreviated labels. The main purpose of these plates is to identify smaller structures within the brain core. In addition, every coronally-sectioned specimen contains high magnification plates of the cortical plate in different areas of the cerebral cortex, and every sagittally-sectioned specimen contains high magnification plates of different lobules of the cerebellar cortex in the midline vermis. Because our emphasis is on development, transient structures that appear only in immature brains are labeled in italics, either directly in some of the high magnification plates or in bold numbers that refer to italicized labels in a Table. During dissection, embedding, cutting, and staining, some of the sections illustrated were torn; that damage is usually surrounded by dashed lines. Finally, an alphabetized Glossary gives brief definitions of most

labels used in the Plates with expanded definitions of all transient developmental structures.

B. Specimens Used All specimens in this volume (designated by the prefix Y) are from the Yakovlev Collection housed in the National Museum of Health and Medicine, Armed Forces Institute of Pathology, Washington, D.C. (Forthcoming volumes will also contain specimens from the Carnegie and Minot Collections.) Over a 40-year span, Paul I. Yakovlev (1894-1983) collected brains and some spinal cords from about 1500 normal and abnormal human specimens, ranging in age from the early second trimester of fetal development through old age (Haleem, 1990). The specimens were fixed in formalin, embedded in celloidin, and cut at 35 µm. The sections were arranged in two sets of consecutively numbered slides. One set was stained for cell bodies (Nissl) using cresyl violet; the other set was stained for myelin using the Loyez modification of Weigert’s hematoxylin. In selecting the specimens, we rejected those with evidence of pathology, and used only those that were well-preserved during preparation and have not deteriorated since then. We ended up with six Nissl-stained coronal specimens, six horizontal specimens, and sixteen sagittal specimens in the age range between GW37 and GW26. From that group, eight specimens were chosen for presentation in this Atlas as most representative of their respective age groups: two coronally sectioned brains, three sagittally sectioned brains, and three horizontally sectioned brains.

C. Photography and Computer Processing The Nissl-stained sections were photographed at low magnification, using a macro lens (Vivitar, 55 mm 1:2.8 auto macro) attached to a Nikkormat 35-mm camera that was mounted on a stand over a fluorescent light board. The magnification varied for each specimen, according to brain size: the section with the largest area that could be accommodated within the field of view set the magnification for all sections of a particular specimen. For better resolution of select regions and structures, most sections were also photographed

2

INTRODUCTION at higher magnifications with a Nikkormat 35-mm camera attached to a 12-cm Leitz/Wetzlar lens with bellows. All photographs were taken with a green filter to increase the contrast of the black and white film (Kodak technical pan #TP442). The film was developed at 20°C for 6 to 7 minutes in Kodak HC110 developer (dilution F), followed by Kodak stop bath for 30 seconds, Kodak fixer for 5 minutes, Kodak hypo clearing agent for 1 minute, running water rinse for 10 minutes, and a brief rinse in Kodak photo-flo before drying. The negatives were scanned at 2700 dots-per-inch (dpi) with a Nikon Coolscan-1000 35-mm film scanner which was interfaced to a PowerPC G3 Macintosh computer, running Adobe Photoshop (version 5.02) with a plug-in Nikon driver. To capture the subtle shades of gray, the negatives were scanned as color positives, inverted, and converted to grayscale. Using the enhancement features built into Adobe Photoshop and the additional features of Extensis Intellihance, adjustments were made to increase contrast and sharpness. When the image resolution was set to 300 dpi, a full-size photographic file printed at approximately 12 × 10 inches. For the low magnification plates, the images were reduced to fit two images side-by-side on a single plate. For the high magnification plates, the images are shown at full size on separate pages to see structural details in the brain core. Adobe Illustrator was used to superimpose labels and outline structural details on low contrast copies of the Adobe Photoshop files.

D. Identification of Brain Structures The late-fetal brain specimens illustrated in this volume contain virtually all the structures found in the mature brain. Hence, these could be identified with some assurance by relying on classical textbooks of neuroanatomy (Ranson and Clark, 1959; Ariëns Kappers et al., 1967; Crosby et al., 1962; Truex and Carpenter, 1969; Brodal, 1981). We also consulted treatises dealing with specific regions of the mature and maturing human brain: the cerebral cortex (Mai et al., 1997; Warner, 2001); the basal telencephalon (Ulfig, 1989; Martin et al., 1991); the amygdala (Sims and Williams, 1990; Amaral et al., 1992; Setzer and Ulfig, 1999), the thalamus (Walker, 1938; Forutan et al., 2001); the hypothalamus (Nauta and Haymaker, 1969; Koutcherov et al., 2002); the visual system (Polyak, 1957); the auditory brainstem nuclei (Moore, 1987; Moore et al., 1999); the nuclei of the pons and the medulla (Paxinos and Huang, 1995); and the cerebellum (Angevine et al., 1961). Since fiber tracts were not stained in our material, many identifications (particularly in the brainstem) posed some difficulties; any label followed by a question mark indicates that we are not completely sure of the identity. The late-fetal specimens examined in this volume contain only remnants of embryonic brain structures that are prominent at earlier stages of development. In contrast to the mature human brain, there are no comprehensive textbooks available on the morphogenesis of the developing human brain through its entire course. There are several book chapters and reviews available, but these deal with select brain regions and a few stages of human brain development (Moore,

1987; Moore et al., 1999; Setzer and Ulfig, 1999; Forutan et al., 2001; Koutcherov et al., 2002). Therefore we relied heavily on our experimental work in the developing rat brain to identify embryonic structures. For those studies, we labeled proliferating cells in the germinal matrices with 3H-thymidine injections at daily intervals through the entire prenatal period, and every other day up to weaning. By varying survival times after 3H-thymidine exposure, we used autoradiography to establish timetables of neurogenesis, traced the speed and route of neuronal and glial migration, and documented settling patterns in the maturing brain. The results of these studies were published over a period of 30 years in various journals (Journal of Comparative Neurology, Experimental Neurology, International Journal of Developmental Neuroscience, Brain Research, and others), and were summarized in monographs (Altman and Bayer, 1982, 1984, 1986), review articles (Altman, 1992; Altman and Bayer, 2003a; Bayer and Altman, 1995a, 1995b; 2004; Bayer et al., 1995), and books (Bayer and Altman, 1991; Altman and Bayer, 1997, 2001). In an early study (Bayer et al., 1993), we presented evidence for some parallels in the early development of the rat brain and human brain. That motivated us to undertake this extensive and in-depth survey of human brain development and interpret it in the light of our experimental rat data. Based mostly on an analysis of younger fetuses and embryos, we identify several embryonic brain structures that either disappear or leave only vestiges behind in the mature brain. These embryonic structures in third trimester fetuses include: (i) vestiges of the primary germinal matrix, the neuroepithelium, at a few sites; (ii) the secondary germinal matrix, the subventricular zone, that replaces the neuroepithelium at other sites; (iii) other secondary germinal matrices that form at some distance from the ventricles, such as the external germinal layer of the cerebellar cortex or the subgranular zone of the hippocampal dentate gyrus; (iv) migratory streams, such as the rostral and lateral migratory streams of the cerebral cortex; (v) areas that contain neurons that sojourn in transitory fields before settling in their final locations, such as the stratified transitional fields in the neocortex; (vi) glioepithelia along several fiber tracts; and (vii) dispersed sites of glial proliferation that precede the myelination of fiber tracts, known as myelination gliosis. At the outset of its development, the proliferative neuroepithelium is the sole constituent of the brain; it is composed of pluripotent stem cells that are the ultimate source of all the neurons and glia of the central nervous system. Following a precise spatio-temporal pattern, the neuroepithelial cells generate postmitotic large and midsize neurons that move out to form the brain’s gross circuitry. While the cells of the neuroepithelium look alike along the entire neuraxis, regions and patches can be distinguished that differ in the time course of their growth (thickening and expansion) and decline (thinning and shrinking), and in the dynamics of their cell proliferation. At first approximation, these neuroepithelial patches or mosaics are identified by their position and are distinguished in such general terms as the amygdaloid neuroepithelium, hippocampal neuroepithelium, or occipital neuroepithelium. The virtual disappearance of the neuroepithelium by the third trimester indicates that the pro-

duction of the brain’s gross-circuitry neurons has ended earlier. At many sites, the neuroepithelium also gives rise to secondary germinal matrices with more limited potencies. Several secondary germinal matrices persist in the third-trimester brain. Some interneurons may still be generated in the subventricular zone of the cerebral cortex. The cortical subventricular zone is also generating glial cells that will disperse throughout the cortex. There are several secondary germinal matrices at some distance from the ventricles that produce neurons during the third trimester and even for some time after birth. The external germinal layer of the cerebellar cortex is generating granule, basket and stellate cells. The subgranular zone of the hippocampus is generating granule cells of the dentate gyrus. Also prominent are several migratory streams during the third trimester. One of these, the rostral migratory stream contains, among other cell types, granule cells that settle in the olfactory bulb and it is also a source of glia. Migrating cells in some brain regions stop in sojourn zones for varying lengths of time before settling in their final locations. In the human neocortex these sojourning cells form alternating layers with afferent, efferent and commissural (callosal) fibers that we call stratified transitional fields. Banding patterns in these fields differ considerably in the frontal, paracentral, occipital and temporal lobes (Altman and Bayer, 2003b) and their vestiges are still present throughout the third trimester. These fields have been postulated to be sites where connections of the cerebral cortex are established before neurons settle in the cortical plate; that process is still in progress during the third trimester. The mature stratification of the cortical plate, the primordium of the cortical gray matter, starts to be evident during the third trimester and finishes after birth. Glioepithelia are fate-restriced precursors of oligodendrocytes responsible for the myelination of axons in fiber tracts. Several of these are still prominent during the third trimester beneath the corpus callosum, lining the fornix, and adjacent to some fiber tracts. At other sites glia dispersed within fiber tracts appear to proliferate locally before the onset of myelination. This myelination gliosis is evident at the beginning of the third trimester in the cuneate and gracile fasciculi of the medulla and spinal cord (Bayer and Altman, 2002). A final note. In the first volume of this series dealing with spinal cord development from the early embryonic period through infancy (Bayer and Altman, 2002), we provided quantitative summaries of several ontogenetic trends, such as the area of the neuroepithelium, the area of the ventricular lumen, and the expansion of the white matter and gray matter over the entire span of development. Because this volume deals only with the latest phase of fetal brain development, comprehensive quantitative summaries will be featured in Volume 5 of this series when all the brain studies are completed.

3

INTRODUCTION E. References Altman, J. (1992) The early stages of nervous system development: Neurogenesis and neuronal migration. In: A. Björklund, T. Hökfelt and M. Tohyama (eds.) Handbook of Chemical Neuroanatomy. Volume 10. Ontogeny of Transmitters and Peptides in the CNS, pp. 1-31. Amsterdam: Elsevier. Altman, J. and S. A. Bayer (1982) Development of the Cranial Nerve Ganglia and Related Nuclei in the Rat. (Advances in Anatomy, Embryology and Cell Biology, Vol. 74). Berlin: Springer-Verlag. Altman, J. and S. A. Bayer (1984) The Development of the Rat Spinal Cord. (Advances in Anatomy, Emryology and Cell Biology, Vol. 85). Berlin: Springer-Verlag. Altman, J. and S. A. Bayer (1986) The Development of the Rat Hypothalamus. (Advances in Anatomy, Embryology and Cell Biology, Vol.100). Berlin: Springer-Verlag. Altman, J. and S. A. Bayer (1997) Development of the Cerebellar System in Relation to its Evolution, Structure, and Functions. Boca Raton, FL: CRC Press. Altman, J. and S. A. Bayer (2001) Development of the Human Spinal Cord: An Interpretation Based on Experimental Studies in Animals. New York, NY: Oxford University Press. Altman, J. and S. A. Bayer (2003a) Neuroembryology. In: G. Adelman and B. H. Smith (eds.) Encyclopedia of Neuroscience. (Third edition) Amsterdam: Elsevier. (In press) Altman, J. and S. A. Bayer (2003b) Regional differences in the stratified transitional field and the honeycomb matrix of the developing human cerebral cortex. Journal of Neurocytology, 31:613-632. Amaral, D. G., J. L Price, A. Pitkänen, and S. T. Carmichael (1992) Anatomical organization of the primate amygdaloid complex. In: J. P. Aggleton (ed.) The Amygdala: Neurobiological Aspects of Emotion, Memory, and Mental Dysfunction. New York, NY: Wiley-Liss, pp. 1-66. Angevine, J. B., E. L. Mancall, and P. I. Yakovlev (1961) The Human Cerebellum: An Atlas of Gross Topography in Serial Sections. Boston, MA: Little, Brown. Ariëns Kappers, C. U., G. C. Huber, and E. C. Crosby (1936) The Comparative Anatomy of the Nervous System of Vertebrates, Including Man. Volumes 1-3. New York, NY: Hafner Publishing Company. [Reprint, 1967].

Bayer, S. A. and J. Altman (1991) Neocortical Development. New York, NY: Raven Press.

Mai, J. K., J. Assheuer, and G. Paxinos (1997) Atlas of the Human Brain. San Diego, CA: Academic Press.

Bayer, S. A and J. Altman (1995a) Neurogenesis and neuronal migration. In: G. Paxinos (ed.) The Rat Nervous System (Second edition), pp. 1041-1078. San Diego, CA: Academic Press.

Martin, L. J., R. E. Powers, T. L. Dellovade, and D. L. Price (1991) The bed nucleus-amygdala continuum in human and monkey. Journal of Comparative Neurology, 309:445-485.

Bayer, S. A and J. Altman (1995b) Principles of neurogenesis, neuronal migration, and neural circuit formation. In: G. Paxinos (ed.) The Rat Nervous System (Second edition), pp. 1079-1098. San Diego, CA: Academic Press.

Moore, J. K. (1987) The human auditory brainstem: a comparative view. Hearing Research, 29:1-32.

Bayer, S. A. and J. Altman (2002) Atlas of Human Central Nervous System Development. Volume 1: The Spinal Cord from Gestational Week 4 to the 4th Postnatal Month. Boca Raton, FL: CRC Press. Bayer, S. A. and J. Altman (2004) Development of the telencephalon: Neural stem cells, neurogenesis and neuronal migration. In: G. Paxinos (ed.) The Rat Nervous System (Third edition). San Diego, CA: Academic Press. pp. 27-73. Bayer, S. A., J. Altman, R. J. Russo and X. Zhang (1993) Timetables of neurogenesis in the human brain based on experimentally determined patterns in the rat. Neurotoxicology, 14:83-144. Bayer, S. A., J. Altman, R. J. Russo and X. Zhang (1995) Embryology. In: S. Duckett (ed.) Pediatric Neuropathology, pp. 54-107. Baltimore, MD: Williams & Wilkins. Brodal, A. (1981) Neurological Anatomy in Relation to Clinical Medicine. (Third edition). New York, NY: Oxford University Press. Crosby, E. C., T. Humphrey, and E. W. Lauer (1962) Correlative Anatomy of the Nervous System. New York, NY: The Macmillan Company. Forutan, F., J. K. Mai, K. W. S. Ashwell, S. Lensing-Höhn, D. Nohr, T. Voss, J. Bohl, and C. Andressen (2001) Organisation and maturation of the human thalamus as revealed by CD15. Journal of Comparative Neurology, 437:476-495. Haleem, M. (1990) Diagnostic Categories of the Yakovlev Collection of Normal and Pathological Anatomy and Development of the Brain. Washington, D.C.: Armed Forces Institute of Pathology. Koutcherov, Y., J. K. Mai, K. W. S. Ashwell, and G. F. Paxinos (2002) Organisation of human hypothalamus in fetal development. Journal of Comparative Neurology, 446:301-324.

Moore, J. K., D. D. Simmons, and Y-L. Guan (1999) The human olivocochlear system: organization and development. Audiology and Neuro-otology, 4:311-325. Nauta, W. J. H., and W. Haymaker (1969) Hypothalamic nuclei and fiber connections. In: The Hypothalamus, W. Haymaker, E. Anderson, and W. J. H. Nauta (eds.). Springfield, IL: Charles C. Thomas. pp. 136-209. Paxinos, G., and X-F. Huang (1995) Atlas of the Human Brainstem. San Diego, CA: Academic Press. Polyak, S. (1957) The Vertebrate Visual System, H. Klüver (ed.). Chicago, IL: The University of Chicago Press. Ranson, S. W. and S. L. Clark (1959) The Anatomy of the Nervous System: Its Development and Function (Tenth edition). Philadelphia, PA: W. B. Saunders Company. Setzer, M., and N. Ulfig (1999) Differential expression of calbindin and calretinin in the human fetal amygdala. Microscopy Research and Technique, 46:1-17. Sims, K. S., and R. S. Williams (1990) The human amygdaloid complex: A cytologic and histochemical atlas using Nissl, myelin, acetylcholinesterase and nicotinamide adenine dinucleotide phosphate diaphorase staining. Neuroscience, 36:449-472. Truex, R. C., and M. B. Carpenter (1969) Human Neuroanatomy (6th edition). Baltimore, MD: Williams & Wilkins Company. Ulfig, N. (1989) Configuration of the magnocellular nuclei in the basal forebrain of the human adult. Acta Anatomica, 134:100-105. Walker, A. E. (1938) The Primate Thalamus. Chicago, IL: The University of Chicago Press. Warner, J. J., (2001) Atlas of Neuroanatomy with Systems Organization and Case Correlation. Boston, MA: Butterworth-Heinemann.

4

PART PART II: II:

GW37 GW37 CORONAL CORONAL

yr

up r

rf ro

lg

Centra tr l s al g y Post c u s ru

Pre ce

Su pe

NTAL LOB E RO

rio rf r

M

F

P

O

RA

us

Inferior temporal gyrus

L LOBE

CIPITAL L O BE OC

M id d l e t e m poral g y r

ccipital gyri al o t er La

S

BE LO

ar am g

al fissure La t er rus Superior temporal gy

O r bital gy

Insular gyrus

L

io

Angular l gyrus ina

I n f er

Superior parietal lobule

a c ul ntr e

s yru

al g nt

TE

The approximate cutting plane of this brain is indicated in Figure 2 (facing page) with lines superimposed on the GW37 brain from the Larroche (1967) series. The dorsal part of each section is posterior to the ventral part. This brain is nearly even in mediolateral orientation. For example, the temporal poles on right vs. left sides of the brain appear at the same time (Level 5, Section 611). The sections chosen for illustration are more closely spaced to show small structures in the diencephalon, midbrain, pons, and medulla. Illustrated sections are spaced farther apart when they contain only large brain structures, such as the cerebral cortex, basal ganglia, and cerebellum. Photographs of 21 different Nisslstained sections (Levels 1-21) are shown at low magnification in Plates 1-20. Different areas of the cerebral cortex are shown at very high magnification in Plates 21-30. The core of the brain and the cerebellum are shown at high magnification in companion Plates 31AB-46AB for Levels 5-21.

id

rus

This specimen is case number W-217-65 (Perinatal RPSL) in the Yakovlev Collection. A male infant, weighing 3,057 grams, was born alive on August 10, 1965, and survived for 44 hours. Death occurred because a hyaline membrane obstructed the airway to the lungs. Upon autopsy, a subarachnoid hemmorhage in the left temporal/parietal area of the cerebral cortex was noted. The brain itself, cut in the coronal (frontal) plane in 35-µm thick sections, is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). Although there is no photograph of this brain before it was embedded and cut, the photograph of the lateral view of another GW37 brain that Larroche published in 1967 (Figure 1) is similar to the features of the brain in Y217-65. There are definite divisions between major gyri in all lobes of the cerebral hemispheres (labeled in Figure 1).

M

n

us

s gyru

us gyr l ta on s yru g al nt o fr e l d

PARACENTRAL LOBULE PAR IE TA s

Cerebellar hemisphere Spinal cord

Figure 1. Lateral view of a GW37 brain with major structures in the cerebral hemispheres labeled. (From the photographic series of J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

5

GW37 CORONAL SECTION PLANES LEVEL NUMBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

1711

1611

1501

981 1021 1081 1141 1181 1221 1311 1371

611 691 721 761 831 881

511

361

281

161

Y217-65 contains several immature structures. In the cortical regions of the telencephalon, remnants of the germinal matrices are present in all lobes of the cerebral cortex where the neuroepithelium/subventricular zone may still be generating neocortical interneurons. Remnants of migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields, thin in the occipital lobe, and thicker in the frontal, parietal and temporal lobes. Indeed, thickness variations can be used as identifying criteria for designating a particular cortical germinal matrix as occipital or otherwise. Many neurons, glia, and their mitotic precursor cells are still migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Within the lateral parts of the cerebral cortex, streams of neurons and glia are still in the lateral migratory stream. That stream percolates through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus, and the cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a prominent neuroepithelium/ subventricular zone overlying the striatum and nucleus accumbens where neurons are probably still being generated. The striatal portion can be subdivided into anterolateral, anteromedial, and posterior parts. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Other structures in the telencephalon, such as the septum, fornix, and Ammon’s horn part of the hippocampus, have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle.

SECTION NUMBER Figure 2. Lateral view of the same GW37 brain shown in Figure 1 with the approximate locations and cutting angle of the sections of Y217-65. (From the photographic series of J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

Most of the structures in the diencephalon appear to be settled and are maturing, and the third ventricle is lined by a thin glioepithelium/ ependyma. In the midbrain and anterior pons, there is a slightly thicker and more convoluted glioepithelium/ependyma lining the posterior cerebral aqueduct and anterior fourth ventricle. The posterior pons and entire medulla have a thin glioepithelium/ependyma lining the rest of the fourth ventricle. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is still producing basket, stellate, and granule cells. The germinal trigone is still visible at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia may still be originating here.

6

PLATE 1 GW37 Coronal CR 350 mm Y217-65 Level 1: Section 161

Remnants of the germinal matrix, migratory streams, and transitional fields 1 2

Frontal stratified transitional field Subpial granular layer (cortical)

Interhemispheric fissure

Superior frontal gyrus

Frontal lobe

1 Middle frontal gyrus

2

1

1

Cingulate gyrus

Inferior frontal gyrus

1 1

Orbital gyri Damaged areas in section

Superior rostral gyrus Gyrus rectus

Inferior rostral gyrus

Layer I Cortical plate White matter

7

PLATE 2 Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Subpial granular layer (cortical)



Middle frontal gyrus

2


Claustrum

Orbital gyri

1

1 2

Cortical plate White matter

3

2

gyrus

2

Layer I

Frontal lobe

Cingulate

1 2 3

GW37 Coronal CR 350 mm Y217-65 Level 2: Section 281

1

Lateral fissure

1 2

Corpus callosum Damaged areas in section Gyrus rectus

Inferior rostral gyrus

8

PLATE 3 Remnants of the germinal matrix, migratory streams, and transitional fields 1 Rostral migratory stream (source area) 4 Callosal glioepithelium 2 Frontal neuroepithelium and subventricular zone 5 Anterolateral striatal neuroepithelium and subventricular zone 3 Frontal stratified transitional field 6 Subpial granular layer (cortical)



6

Induseum griseum Layer I

Frontal lobe


4

2 Insular gyrus

Corpus callosum (genu)

m u lu ng Ci

Cingulate gyrus


Caudate (head)

5

1

Cingulate gyrus

Orbital gyri


3

L venatera t r ic l le


3

2

Damaged areas in section

Gyrus rectus Inferior rostral gyrus

Olfactory sulcus

Lateral fissure

Claustrum

9

PLATE 4 Remnants of the germinal matrix, migratory streams, and transitional fields 1 Rostral migratory stream 6 Callosal sling 2 Frontal neuroepithelium and subventricular zone 7 Fornical glioepithelium 3 Frontal stratified transitional field 8 Anterolateral striatal neuroepithelium and subventricular zone Frontal neuroepithelium and subventricular zone neuroepithelium and subventricular zone 4 (intermingled with the source of the 9 Accumbent (intermingled with the source of the rostral migratory stream) 10 Subpial granular layer (cortical)

Interhemispheric fissure Induseum griseum


Frontal lobe

10


3

5 2


Orbital gyri

Lateral ventricle

Fornix (in septum pellucidum)

a are

3


8 6 7

m

us s cle ben Nu um c ac

Insular gyrus

Corpus c allosu

9


l osa call Sub

Basal ganglia

Layer I

Cingulum

Ci n gy gula ru te s

Ca uda Int te ( ern hea al c d) aps Pu tam ule en

5

rostral migratory stream) Callosal glioepithelium


Lateral fissure

4 Gyrus rectus

1

Lateral fissure Claustrum

Olfactory sulcus Olfactory peduncle

10


1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream 7 Anterolateral striatal neuroepithelium and subventricular zone Frontal neuroepithelium and subventricular zone 8 Anteromedial striatal neuroepithelium and subventricular zone Frontal stratified transitional field neuroepithelium and subventricular zone 9 Accumbent (intermingled with the source of the rostral migratory stream) Callosal glioepithelium 10 Septal glioepithelium/ependyma Callosal sling Fornical glioepithelium 11 Subpial granular layer (cortical)

See detail of brain core in Plates 31A and B.


Induseum griseum


Frontal lobe

11



Cingulum

Basal ganglia


Corpus cal

5 6 8 10

Lateral ventricle Fornix

Septum

Subcallosal area

Paracentral lobule


us s cle ben Nu um c ac

9

Insular gyrus

losum

ern C al aud cap ate (he sul ad) e

2

7

Cingulate gyrus

Pu tam en

Precentral gyrus

4

I nt

3

Temporal pole

Superior temporal gyrus

1

Gyrus rectus Olfactory sulcus Orbital gyri

Olfactory peduncle

11

PLATE 6 1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream 7 Lateral migratory stream (cortical) Frontal neuroepithelium and subventricular zone 8 Anterolateral striatal neuroepithelium and subventricular zone Frontal stratified transitional field 9 Anteromedial striatal neuroepithelium and subventricular zone Callosal glioepithelium 10 Strionuclear glioepithelium Callosal sling 11 Diencephalic (preoptic) glioepithelium/ependyma Fornical glioepithelium 12 Subpial granular layer (cortical)





11

12

Dark areas are artifacts of mounting medium crystallization


Primary olfactory cortex (piriform) Middle temporal gyrus


Caudate (body)

Bed nucleus of the stria terminalis Anterior commissure

Preoptic area

7

Fornix

Third ventricle

Olfactory tubercle

11

Optic chiasm

Paracentral lobule

rn al ca ps ul Pu e ta m en

5 9 6 10

Lateral ventricle

te

8

4

Cingulate gyrus

Basal ganglia

Insular gyrus

White matter

Corpus callosum

2

Inferior frontal gyrus?

Cortical plate

Cingulum

3 Precentral gyrus

Layer I

Frontal lobe

In


Lateral fissure

Globus pallidus Nucleus accumbens

1

Endopiriform nucleus

Temporal lobe

Claustrum (infiltrated by the lateral migratory stream)

12


1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 7 Anterolateral striatal neuroepithelium and subventricular zone Frontal stratified transitional field 8 Anteromedial striatal neuroepithelium and subventricular zone Callosal glioepithelium 9 Strionuclear glioepithelium Callosal sling 10 Diencephalic (thalamic) glioepithelium/ependyma Fornical glioepithelium 11 Diencephalic (preoptic) glioepithelium/ependyma Lateral migratory stream (cortical) 12 Subpial granular layer (cortical)



12

Superior frontal gyrus Middle frontal gyrus

Frontal lobe

8

6

9 5

Primary olfactory cortex (piriform)



Anterior commissure

Fornix

10

Preoptic area

6

Middle temporal gyrus

Caudate (body)

Lateral ventricle


Basal ganglia

Corpus callosum

4

le su ap c al rn te In

Paracentral lobule

en

Insular gyrus


White matter

m

7

3

Cingulate gyrus

ta

1

Central sulcus

Cortical plate

Pu

Precentral gyrus

Layer I

Cingulum

2

Postcentral gyrus

Induseum griseum

Third ventricle

Bed nucleus of the stria terminalis Globus pallidus Olfactory tubercle

11

Optic chiasm Parolfactory gyrus

Temporal lobe

Lateral fissure


6


13

PLATE 8 Remnants of the germinal matrix, migratory streams, and transitional fields

Callosal glioepithelium Callosal sling Fornical glioepithelium Lateral migratory stream (cortical)


See this area of cortex in Plates 21 and 22


12

Superior frontal gyrus Precentral gyrus

10

Cingulum

2 1

Central sulcus

7

3 8

Insular gyrus


6


Basal ganglia

9

6

Amygdala

10


ior ter lex An omp c

Re Stria medullaris

Fornix

Hypothalamus

11

Paracentral lobule

s obu Gl

Lateral fissure

us llid pa

Anterior commissure

Corticomedial complex

Basolateral complex

Optic tract Arcuate nucleus


Caudate (body)

Fornix

5

Thalamus

White matter

Corpus callosum

Lateral ventricle

Substantia innominata


4

Cingulate gyrus

Cortical plate

men Puta

Postcentral gyrus

Layer I

Frontal lobe

t te r i c u l na a r b lc e ap l t su le

Frontal stratified transitional field

7 Anterolateral striatal neuroepithelium and subventricular zone 8 Anteromedial striatal neuroepithelium and subventricular zone 9 Strionuclear glioepithelium 10 Diencephalic (thalamic) glioepithelium/ependyma 11 Diencephalic (hypothalamic) glioepithelium/ependyma 12 Subpial granular layer (cortical)

In

Frontal neuroepithelium and subventricular zone

Third ventricle

1 2 3 4 5 6


Temporal lobe

Third ventricle (infundibular recess)


14

PLATE 9 1 2 3 4 5 6

Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field

7 Lateral migratory stream (cortical) 8 Amygdaloid glioepithelium/ependyma 9 Posterior striatal neuroepithelium and subventricular zone 10 Strionuclear glioepithelium 11 Diencephalic (thalamic) glioepithelium/ependyma 12 Diencephalic (hypothalamic) glioepithelium/ependyma 13 Subpial granular layer


Superior frontal gyrus Precentral gyrus

13 2

Central sulcus

9

Insular gyrus

3

Cingulate gyrus

5

10

7

11

Basal ganglia Substantia innominata

12 Amygdala

6 Inferior temporal gyrus Damaged areas in section

Corpus callosum

4

8

Hypothalamus

Optic tract Arcuate nucleus

Fornix

Dorsal complex

n ter us In llid pa us b o Gl Anterior Corticocommissure medial complex us cle nu l Basolateral ra nt complex Ce

Parahippocampal gyrus


Paracentral lobule

Caudate (tail)

men Puta


7

White matter

Lateral ventricle

Thalamus


Cortical plate

Cingulum

1 Postcentral gyrus

Layer I

Frontal lobe

V co ent m ra pl l ex al c ap su l e


Remnants of the germinal matrix, migratory streams, and transitional fields

Third ventricle


Entorhinal cortex

Temporal lobe


15

PLATE 10 Remnants of the germinal matrix, migratory streams, and transitional fields Frontal/paracentral neuroepithelium and subventricular zone Frontal/paracentral stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

9 Alvear glioepithelium 10 Lateral migratory stream (cortical) 11 Amygdaloid glioepithelium/ependyma 12 Posterior striatal neuroepithelium and subventricular zone 13 Strionuclear glioepithelium 14 Diencephalic (thalamic) glioepithelium/ependyma 15 Diencephalic (hypothalamic) glioepithelium/ependyma 16 Subpial granular layer



Superior frontal gyrus Precentral gyrus Central sulcus

2 Postcentral gyrus Insular gyrus

1 12

Cingulum

3

Cingulate gyrus

13

Corpus callosum

Lateral ventricle

5 Third ventricle

Caudate (tail)

Dorsal complex


9

11

8

7

Hippocampus

6

Inferior temporal gyrus Parahippocampal gyrus

Mammillary body Entorhinal cortex

White matter

Lateral fissure

15

10

Layer I

Fornix

Central complex Periventricular Basal complex ic ganglia s lams Subthalamus obbuu thacleu Gllo lidus G b u Optic S nu al p tract CorticoHypol medial Anterior thalamus erebrnacle complex commissure l C edu a A m yg r e p o la t d a la B a s m p le x Central nucleus co



4

Pa ra lo cen bu tr l e al

men Puta

14

Thalamus


Cortical plate

Frontal lobe

16

V co ent m ra pl l ex

1 2 3 4 5 6 7 8


Ammon's horn

Lateral ventricle

Temporal lobe

Claustrum

16

PLATE 11 1 2 3 4 5 6 7 8

Frontal/paracentral neuroepithelium and subventricular zone Frontal/paracentral stratified transitional field

9 Alvear glioepithelium 10 Subgranular zone (dentate) 11 Lateral migratory stream (cortical) 12 Posterior striatal neuroepithelium and subventricular zone 13 Strionuclear glioepithelium 14 Diencephalic (thalamic) glioepithelium/ependyma 15 Subpial granular layer (cortical)

Callosal glioepithelium Callosal sling Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field


Precentral gyrus Central sulcus

Induseum griseum

2

11


8


7

Lateral ventricle

Basal Optic ganglia tract Subt

White matter

Caudate (tail)

Fornix

14 hala

m us

Hippocampus

9 10

Inferior temporal gyrus Fusiform gyrus Parahippocampal gyrus Damaged areas in section

4

13 Thalamus

12

Cingulum Corpus callosum

Pa ra lo cen bu tr l e al

6

Dorsal complex Third ventricle Central complex

Ventral complex

Temporal lobe

Putamen


12

3

Cingulate gyrus

Fimbria/fornix

Midbrain

Red nucleus

Tegmentum

bs ta nt re ia br ni al gr pe a du nc le

1 Insular gyrus

Cortical plate Layer I

Frontal lobe

15

Postcentral gyrus


5

Pons

Caudate (tail)

Lateral ventricle Dentate gyrus

Su



Ce


Ammon's horn Subiculum

Temporal lobe

Entorhinal cortex Pontine gray Middle cerebellar peduncle

Lateral fissure

17


Remnants of the germinal matrix, migratory streams, and transitional fields Paracentral neuroepithelium and subventricular zone Paracentral stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone



Precentral gyrus Central sulcus

Layer I Cortical plate

Postcentral gyrus

15 2


7

13

Lateral geniculate body

Hippocampus

8 9 10

Fusiform gyrus

This section became brittle and was fractured during staining and attachment to the slide.

Parahippocampal gyrus Damaged areas in section

Caudate (tail)

Lateral ventricle

Posterior complex

Third ventricle (pineal recess)

Midbrain Tegmentum

6


4

14 Central

Ventral complex

complex Cerebral aqueduct

lo bu le

Pons

Temporal lobe

Fimbria/fornix Posterior complex

Red nucleus

ta nt ia ni re br gr al pe a du nc le

12

Corpus callosum

White matter

Fornix

Thalamus Basal ganglia

Cingulum

Putamen

11

12

m ectu Pret


1

Cingulate gyrus

Pa ra ce nt ra l

5

Caudate (tail)

Lateral ventricle Dentate gyrus Ammon's horn

bs

Insular gyrus

3

Induseum griseum

Ce

Temporal stratified transitional field

9 Alvear glioepithelium 10 Subgranular zone (dentate) 11 Lateral migratory stream (cortical) 12 Posterior striatal neuroepithelium and subventricular zone 13 Strionuclear glioepithelium 14 Mesencephalic glioepithelium/ependyma 15 Subpial granular layer (cortical)

Su

1 2 3 4 5 6 7 8

Subiculum

Temporal lobe

Entorhinal cortex Middle cerebellar peduncle Pontine gray

Lateral fissure

18



Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5 6 7

8 Temporal stratified transitional field 9 Alvear glioepithelium 10 Subgranular zone (dentate) 11 Posterior striatal neuroepithelium and subventricular zone 12 Strionuclear glioepithelium 13 Mesencephalic glioepithelium/ependyma 14 Subpial granular layer (cortical)

Paracentral neuroepithelium and subventricular zone Paracentral stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone


Interhemispheric fissure Precentral gyrus Central sulcus

Postcentral gyrus

Cingulum

2

Superior temporal gyrus Middle temporal gyrus


11

3 12

Hippocampus

8 7


9

Cingulate gyrus

Medial geniculate body

10

6

Fusiform gyrus Parahippocampal gyrus

Pretectum

Tectum

Cerebral aqueduct

Midbrain Tegmentum

Pons

13

Parietal lobe

Caudate (tail)

Fornix

5

P co oste m ri pl or ex

Fimbria/fornix

5

Central gray

Oculomotor nuclear complex (III) Superior cerebellar peduncle

Temporal lobe

Caudate (tail)

Lateral ventricle Dentate gyrus Ammon's horn Subiculum

Temporal lobe

Raphe nuclear complex Middle cerebellar peduncle Pontine gray Transpontine corticofugal tract


White matter

Corpus callosum

Lateral ventricle

4

Thalamus


Cortical plate

Para cent ral l obul Induseum griseum e

14 1 11

Layer I

Reticular tegmental nucleus

Lateral fissure

19


Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4

Fornical glioepithelium

5

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field

6

Temporal neuroepithelium and subventricular zone

Paracentral/parietal neuroepithelium and subventricular zone Paracentral/parietal stratified transitional field Callosal glioepithelium

7 Temporal stratified transitional field 8 Alvear glioepithelium 9 Subgranular zone (dentate) 10 Posterior striatal neuroepithelium and subventricular zone 11 Strionuclear glioepithelium 12 Mesencephalic glioepithelium/ependyma 13 Subpial granular layer (cortical)

See detail of brain core in Plates 40A and B. Interhemispheric fissure Precentral gyrus Central sulcus Layer I

Postcentral gyrus

Cortical plate

Supramarginal gyrus

13 2 1 10



Induseum griseum

3

Cingulate gyrus

Cingulum

4

11

Fornix P c o o ste m ri pl or ex

Thalamus

7 6

Hippocampus

9

5

Tectum

12 Midbrain Tegmentum

Inferior temporal gyrus Fusiform gyrus Parahippocampal gyrus

Pons

Corpus callosum

Parietal lobe

Lateral ventricle

Stria terminalis

8

White matter

lobule Paracentral lobule

Caudate (tail)

4

Superior colliculus Central gray Cerebral aqueduct Superior cerebellar peduncle

Fimbria/fornix

Dentate gyrus

Subiculum

Lateral ventricle Ammon's horn

Temporal lobe

Raphe nuclear complex Nerve V Middle cerebellar peduncle Pontine gray Transpontine corticofugal tract Reticular tegmental nucleus

20



See detail of brain core and cerebellum in Plates 41A and B.

1 2 3 4

Paracentral/parietal neuroepithelium and subventricular zone

7


Paracentral/parietal stratified transitional field

8

Alvear glioepithelium

Callosal glioepithelium

9

Subgranular zone (dentate)


5


6



Postcentral gyrus

10 Mesencephalic glioepithelium/ependyma 11 External germinal layer (cerebellum) 12 Subpial granular layer (cortical)

Interhemispheric fissure Layer I



White matter

1

Supramarginal gyrus

12

2

7

Induseum griseum

3

8

Cingulate gyrus

4

Choroid plexus

6

lobule Paracentral lobule

9


Fimbria/fornix

Hippocampal commissure

4 Dentate gyrus

Tectum

Midbrain

Superior colliculus Central gray

10 Isthmus

Cerebellum Fusiform gyrus?

Parietal lobe

Corpus callosum


5

Lateral ventricle

Cingulum

us mp ca o pp Hi

Inferior temporal gyrus Dark areas are artifacts of mounting medium crystallization

Cortical plate

Inferior colliculus

Cerebral aqueduct Superior cerebellar peduncle

Ammon's horn Subiculum

Temporal lobe

Hemisphere

Pons 11

Medulla

Raphe nuclear complex Middle cerebellar peduncle Nerve VIII Pontine gray Superior olive Inferior olive Pyramid

21

PLATE 16 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4


5


Paracentral/parietal neuroepithelium and subventricular zone Paracentral/parietal stratified transitional field Callosal glioepithelium


6 Temporal neuroepithelium and subventricular zone 7 Temporal stratified transitional field 8 Alvear glioepithelium 9 Mesencephalic glioepithelium/ependyma 10 External germinal layer (cerebellum) 11 Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 42A and B. Interhemispheric fissure Postcentral gyrus

Layer I


11

Angular gyrus

1

2

8 7

Parietal lobe

Cingulum

Lateral ventricle

Corpus callosum (splenium)

5

Tectum

Midbrain

um

C

e er

ll be

H

em

Fimbria/fornix


hippocampal gyrus

10 Damaged areas in section

4

s pu am c o pp Hi Para-

Inferior temporal gyrus Fusiform gyrus

Cingulate gyrus

3 Choroid plexus

6

White matter

Induseum griseum

Supramarginal gyrus


Cortical plate

Paracentral lobule

9 Isthmus

Ammon's horn

Subiculum Inferior colliculus Cerebral aqueduct/ Fourth ventricle

Temporal lobe

re

he isp

Pons Medulla

Locus coeruleus Motor nucleus (V) Middle cerebellar peduncle Motor nucleus (VII) Inferior olive Pyramid Raphe nuclear complex

22


Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5 6

7 Temporal neuroepithelium and subventricular zone 8 Temporal stratified transitional field 9 Medullary glioepithelium/ependyma 10 Pontine glioepithelium/ependyma 11 External germinal layer (cerebellum) 12 Subpial granular layer (cortical)

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Callosal glioepithelium Cingulate neuroepithelium, subventricular zone, and stratified transitional field Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

See detail of brain core and cerebellum in Plates 43A and B. Interhemispheric fissure


Layer I Angular gyrus

Parietal lobe Cingulum

3

Cingulate gyrus

Lateral ventricle

Choroid plexus


5

7 6

8

4

Occipital gyrus

H

11

Flocculus


us ) yr ea e gal ar t a i ul n n g le Ci trosp (re

11

Vermis

Occipital lobe

Temporal lobe

10

m llu be here e r p Ce emis

Fusiform gyrus


White matter

Precuneus

2

1

Su pramarginal gyrus


Cortical plate

12

Pons

9

Superior cerebellar peduncle

Fourth ventricle

Middle and inferior cerebellar peduncles

Medulla

Vestibular nuclear complex

Inferior olive Pyramid Raphe nuclear complex

23

PLATE 18 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5 6

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Callosal glioepithelium (intermingled with cingulate neuroepithelium and subventricular zone) Cingulate stratified transitional field Occipital neuroepithelium and subventricular zone Occipital stratified transitional field


7 Temporal neuroepithelium and subventricular zone 8 Temporal stratified transitional field 9 External germinal layer (cerebellum) 10 Germinal trigone (cerebellum) 11 Medullary glioepithelium/ependyma 12 Subpial granular layer (cortical) See this area of cortex in Plates 27 and 28

See detail of brain core and cerebellum in Plates 44A and B. Interhemispheric fissure Superior parietal lobule

Layer I

Cortical plate

Angular gyrus

Supramarginal gyrus

12 1

3

Choroid plexus

Middle temporal gyrus Inferior temporal gyrus

Lateral ventricle

8

4

7

6

Corpus callosum

Primary visual cortex

Cuneus

9

um l l re be re isphe e C m 10 He 9

Precuneus

Cingulate gyrus (retrosplenial area)

5

Lingula?


Precuneus

2

Parietal lobe

Occipital lobe

Vermis

Temporal lobe

De ep nu cle i

Vermis

Floccular peduncle

Fourth ventricle

11 Medulla

Choroid plexus

Cuneate nucleus Spinal nucleus (V) Pyramidal decussation


White matter

24



5 6 7 8

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

Temporal neuroepithelium and subventricular zone Temporal stratified transitional field External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of cerebellum in Plates 45A and B.


Precuneus


Cortical plate

Angular gyrus

8

2 1 Middle temporal gyrus

5 6

Parietooccipital sulcus


3

Calcarine sulcus

Cuneus

Occipital lobe

4 7

Lingula?

m He Damaged areas in section

7

Parietal lobe

isp

Vermis

re

he

Vermis

De ep nu cle i

Cerebellum

White matter

Lateral ventricle

Temporal lobe

Inferior temporal gyrus?

25

PLATE 20 GW37 Coronal, CR 350 mm, Y217-65



5 6 7 8

Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

Level 20: Section 1611 See detail of cerebellum in Plates 46A and B (top).

External germinal layer (cerebellum) Subpial granular layer (cortical)

Precuneus


8 Angular gyrus

2 Cuneus

1 Middle temporal gyrus


3 5

6

Cuneus

Cerebellum

7 m He

isp

Calcarine sulcus


Lateral ventricle

Temporal lobe

4 Lingula?


Layer I

Parietal lobe

Occipital lobe

Vermis

re he


Level 21: Section 1711 See detail of cerebellum in Plates 46A and B (bottom). Precuneus 8 Interhemispheric fissure

Angular gyrus

3

Lateral ventricle

4

Calcarine sulcus Cuneus


Lingula?

7

Parietal lobe

Cuneus

2 1

See this area of cortex from section 1751 in Plates 29 and 30


ere sph i m He Cerebellum

Layer I Cortical plate White matter Parieto-occipital sulcus

Occipital lobe

26

PLATE 21 GW37 Coronal CR 350 mm Y217-65 Level 8: Section 761 FRONTAL CORTEX

See the entire section in Plate 8. For detail, see Plate 22.

See Plate 22

27

PLATE 22 FRONTAL CORTEX I I Latest arriving cells

II

II III

III IV

IV V

VI

V

VII

VI

VII

White matter

28

PLATE 23 GW37 Coronal CR 350 mm Y217-65 Level 13: Section 1081 CORTEX OF THE PRECENTRAL GYRUS (Primary motor cortex)

24 See Plate


29

PLATE 24 CORTEX OF THE PRECENTRAL GYRUS

Subpial granular layer (transient proliferative glial matrix)

I Latest arriving cells

I

II

II

III

III

IV

IV

Large neurons are Betz pyramidal cells

V

V

VI VI

VII

VII White matter

30

PLATE 25 GW37 Coronal CR 350 mm Y217-65 Near Level 14: Section 1161 CORTEX OF THE POSTCENTRAL GYRUS (Primary sensory cortex)

See Plate 26

31

PLATE 26 CORTEX OF THE POSTCENTRAL GYRUS


I


II

II

III

III

IV IV

V V

VI VI

VII VII White matter

32

PLATE 27 GW37 Coronal CR 350 mm Y217-65 Level 18: Section 1371 PARIETAL CORTEX


See Plate 28

33

PLATE 28

PARIETAL CORTEX I


II

II

III

III

IV

IV

V

V

VI

VI

White matter VII

VII

34

PLATE 29

See Plate 30

GW37 Coronal CR 350 mm Y217-65 Near Level 21: Section 1751 STRIATE/PERISTRIATE CORTICAL TRANSITION AREA

Band of Gennari

35

PLATE 30 STRIATE CORTEX

Latest arriving cells

Band of Gennari

PERISTRIATE CORTEX

I II

I

III

II

IVa

III

IVb IV

IVc V Dense cell accumulations

V

VI VI VII VII

White matter

36

PLATE 31A GW37 Coronal CR 350 mm Y217-65 Level 5: Section 611

See the entire section in Plate 5.

37

PLATE 31B Germinal and transitional structures in italics Callosal glioepithelium Subpial granular layer

Cingulum


Stria terminalis?

SEPTUM Septal glioepithelium/ ependyma Subcallosal area

Nucleus accumbens


Putamen

Globus pallidus Dorsal tenia tecta

White matter

Ventral striatum Anterior commissure

I n s u la r g y r u s

Accumbent neuroepithelium and subventricular zone (intermingled with the source of the rostral migratory stream)

Medial septal nucleus Lateral septal nucleus


E xt e str rnal capsule um


Lateral ventricle

au

BASAL GANGLIA

Cave of the septum

Columns of fornix

Anteromedial striatal neuroepithelium and subventricular zone

Cell bridges between the caudate and putamen

y)

Cl

Callosal sling Anterolateral striatal neuroepithelium and subventricular zone

(bod

ca Ca ps uda ule te n (an ucl ter eus ior (h e lim ad) b)

Corpus callosum


Lateral fissure

Cingulate gyrus

Induseum griseum

In ter na l


Frontal lobe

Uncinate fasciculus

Endopiriform nucleus Superior temporal gyrus

Olfactory sulcus

Gyrus Rostral rectus migratory stream Orbital gyri

Olfactory peduncles

Temporal pole

38

PLATE 32A GW37 Coronal CR 350 mm, Y217-65 Level 6: Section 691


39

PLATE 32B Frontal neuroepithelium and subventricular zone

Germinal and transitional structures in italics

Callosal sling



Subpial granular layer Interhemispheric fissure

Cingulum

Frontal lobe

Cingulate Induseum gyrus griseum

SEPTUM Fornix

Anteromedial striatal neuroepithelium and subventricular zone Choroid plexus

Vena terminalis Subfornical organ?

te

Stem cells of choroid plexus

Putamen

In

Strionuclear glioepithelium

External capsule

s


yru

Cave of the septum

Anterolateral striatal neuroepithelium and subventricular zone

Lateral ventricle

g I n s ular

ody) llosum (b

rn al ca ps Ca ul ud e( at en an uc te leu r io s( bo rl dy im ) b)

Corpus ca

C lau

Anterior commissure Lateral migratory stream (extends toward olfactory tubercle)

Bed nucleus of the stria terminalis

PREOPTIC AREA


SUBSTANTIA INNOMINATA

Layers III-IV Layer II Small islands of Calleja

Diagonal band of Broca (vertical limb)

Olfactory tubercle

ary im Pr

White matter

o olfact ry c

ortex (

Layer I



)

m for

Primary olfactory cortex

Layer I

Uncinate fasciculus

Ventral striatum

Nucleus accumbens

Lateral fissure

Cortical plate

Olfactory part of the anterior commissure

Lateral preoptic area

Diencephalic (preoptic) glioepithelium/ependyma

u str u m

Globus pallidus (external segment)

Fornix

C la

BASAL GANGLIA

ri Pi

Lateral migratory stream (infiltrates claustrum and endopiriform nucleus)

strum

Infiltrating fibers of the stria terminalis


Lateral olfactory tract

Large island of Calleja Diffuse fibers of the medial forebrain bundle Medial preoptic area Third ventricle (preoptic recess)

Optic chiasm


Rostral migratory stream

Temporal lobe Middle temporal gyrus

40



41

PLATE 33B

Cave of the septum

Ca


Third ventricle rum

BASAL GANGLIA Lateral migratory stream (extends toward olfactory tubercle)

PREOPTIC AREA

Putamen

Lateral preoptic area Magnocellular preoptic nucleus

An

t e ri

o r co

Ventral striatum SUBSTANTIA INNOMINATA

Periventricular preoptic nucleus

Layers III-IV

mary ol Pri

Medial forebrain bundle?

L at

era

l

c to olfa

ry t

ra c

t


)

Layer II

Optic chiasm

White matter

Layer I

Temporal lobe

Lateral migratory stream (extends into the temporal lobe)

Layer I

m


Suprachiasmatic nucleus

Lateral fissure

Cortical plate

tory cor fac t

Sexually dimorphic nucleus

Medial preoptic area

Uncinate fasciculus

mmissure

Olfactory tubercle Endopiriform nucleus


External capsule

Globus pallidus (internal segment)

Fornix

Preoptic glioepithelium/ependyma

Stria terminalis

Choroid plexus

Claust

Lateral migratory stream (infiltrates claustrum and endopiriform nucleus)

Subfornical organ

us llid nt) pa me us eg ob l s Gl erna t (ex

Subpial granular layer


Insular gyrus


Fornix

ter na lc ap su le

Fornical glioepithelium Anteromedial striatal neuroepithelium and subventricular zone

Claustrum


In


Frontal lobe

Lateral ventricle

(an ter ior lim b)

) us callosum (body p r o C

ud at (b o e n u d y c le u ) s

Cingulate gyrus


Cingulum

or rif

Callosal sling


Pi


( ex



42



43

PLATE 34B Cingulate gyrus

Choroid plexus Fornix

Subfornical organ Anteroventral Foramen of Monro nucleus

Lateral migratory stream (infiltrates the claustrum)

VEN COMTRICUL PLEX AR

Third ventricle

Paratenial nucleus

Fornix

Supraoptic nucleus

Glioepithelium (optic tract)

In

Ansa lenticularis

Optic tract

Infundibular recess Arcuate nucleus

Lateral migratory stream (extends to amygdala) Subpial granular layer

Layer I

Insular gyrus

Intercalated cell groups

Anterior commissure


Ventromedial nucleus

Cortical plate

External capsule


a Broc nd ofmb) a b l Anterior l li ona Diag orizonta amygdaloid (h area

Medial forebrain bundle

ANTERIOR HYPOTHALAMUS

Nucleus of the lateral olfactory tract? Amygdalohippocampal area?


Lateral hypothalamic area

White matter

Putamen Me d

Paraventricular nucleus

Thalamic glioepithelium/ ependyma


AMYGDALA

Reticular nucleus

THALAMUS

Hypothalamic glioepithelium/ependyma

Lateral migratory stream (extends to temporal cortex)

Anteromedial nucleus

Mammillothalamic tract

lary lamina ul

BASAL GANGLIA

Anterodorsal Vental anterior nucleus nucleus

Stria medullaris

PERI

RE


OR RI X TE LE ANOMP C

Stria terminalis L RA X LT NT PLE BE VE M R CO LA CU TI


Stem cells of choroid plexus Cave of the septum

ter na lc ap su le



(an ter ior lim b)

Corpus callosum (body) Frontal neuroepithelium and subventricular zone

Frontal lobe

Ca ud at (bo e nu dy cleu ) s

Lateral ventricle

Claustrum

Induseum griseum




Cingulum


Callosal sling Fornical glioepithelium

Cortical nuclei

Medial nucleus Central nucleus

Uncinate fasciculus

dorsal Lateral nucleus ventral

Basal nucleus

Streams of cells migrating into the basolateral nuclear complex of the amygdala

Temporal lobe

Lateral fissure

44


9 See the entire section in Plate 9.

45

PLATE 35B Germinal and transitional structures in italics

Interhemispheric Induseum Callosal sling fissure griseum Fornical glioepithelium Cingulate gyrus Callosal Corpus callosum glioepithelium (body)

Fornix

OM PL

LT

EX

SUBTHA LAMUS

BASAL GANGLIA

ra nt Ce

l n.

Basal nucleus of Meynert

Third ventricle

Zona incerta

Fornix

AMYGDALA

Lateral hypothalamic Optic area tract

Ventromedial nucleus Arcuate nucleus

us

u c le


dorsal

Basal nucleus Lateral nucleus

n al

ventral

ex

cort


Central nucleus

Medial nucleus

Cortical nucleus Accessory basal nucleus

orhi

Amygdalohippocampal area

Uncinate fasciculus


Ent

Amygdaloid glioepithelium/ ependyma


Ansa lenticularis

ior re ter ssu An mi m co

Lateral migratory stream (extends to amygdala)

ule


Internal capsule/ cerebral peduncle junction

Dorsomedial nucleus



Reuniens nucleus

Massa intermedia


aps

m

HYPOTHALAMUS Lateral migratory stream (extends to temporal cortex)

u la

cula r n .

entri

rav

Pa n tra

so

Insular gyrus

Claustrum

BE

AR C

R

P a r a ce

r Do

Lateral fissure

n ame Put

Third ventricle

idus pall nt) bus segme a l Glo amin erna ary l (ext ull ed M

LA

ICUL

CU

EX PL L M A X CO TR LE EN P C OM C

ENTR

AL

TI


RS

RE

THALAMUS

Stria medullaris


PERIV

DO

L RA X NT PLE VEOM C

Stria terminalis

Subfornical organ

l capsule Externa

ANTERIOR COMPLEX

Vental anterior nucleus

tic

Cave of the septum




White matter Cortical plate Layer I

rn

o nr AnteroMo f ventral no e nucleus ram o F

lc


Re

Posterior striatal neuroepithelium and subventricular zone

Choroid plexus

Int ern a


Frontal lobe

Caudate nucleus (tail)

ed


Lateral ventricle

ia l ll nu at er cle u s al nu cle us


Temporal lobe

46

PLATE 36A GW37 Coronal CR 350 mm, Y217-65 Level 10: Section 831 881


47

PLATE 36B Subpial granular layer Interhemispheric fissure

Fornical glioepithelium Frontal/paracentral stratified transitional field

Corpus callosum (body)

M PL EX

ps ca u le

For nix

r al n

ate al l

R et

nt r

Ce

Lateral mammillary nucleus

le nc du e Optic lp ra tract reb e C ln asa

Acc esso ry b

Cortical nucleus


Globus Pallidus Internal segment

uc

Central nucleus

le u

Basal nucleus Lateral ventricle

Alvear glioepithelium Layer I

Entorhinal cortex



ior Anterssure i comm


Insular gyrus

External segment

eus ucl cn i m ala bth u S

Medial mammillary nuclei

HIPPOCAMPUS

Lateral fissure

Forel's fields

Supramammillary nucleus

Lateral nucleus

Zona incerta

HYPOTHALAMUS

AMYGDALA

u cle u s

Para ventr icula r nuc leus

R CO

al rn


Ansa lenticularis and ventral amygdalofugal fibers

Reuniens nucleus

Third ventricle

US

Ventral medial nucleus

s

P

Massa intermedia

Putamen

Centromedian nucleus

ULA

M

LT

ALAM


Ventral anterior nucleus

Claustrum

TRIC

CO

BE

SU BTH

IVEN

AL

AR

EX PL M CO

Clau stru m

PER

TR

UL

L RA NT VE

T IC

X

Dorsomedial nucleus

le l cap su Externa

X LE MP CO AL RS DO

CEN

RE

LE

In te

BASAL GANGLIA

Third ventricle


Stria medullaris


White matter

Anteroventral nucleus

Subfornical organ

Cave of the septum

THALAMUS


Choroid plexus

Fornix ANTERIOR COMPLEX

Paracentral lobule

Caudate nucleus (body)

i c u la


Stria terminalis


Lateral ventricle

Induseum griseum


Lateral migratory stream (extends to temporal cortex)

Cingulum

Cingulate gyrus


Frontal/paracentral neuroepithelium and subventricular zone



r n u cl e u s

Callosal sling

Layer II (stellate cell islands) Layer III Layer IV (lamina dessicans) Layers V-VI


Ammon's horn

Temporal lobe

Uncinate fasculus

48



49

PLATE 37B Callosal glioepithelium

Paracentral neuroepithelium and subventricular zone

Induseum griseum


Cingulum Lateral ventricle Choroid plexus



Fornix

le us al nuc ntr ce

s

r n u cle u ic u la

R et

Stria terminalis

Optic tract

Choroid plexus

m ole c u l

a gr ni ia

Su

bs

ta

nt

or tum iens tra midal la a

no m

tu

Temporal lobe

PONS

Den ta

Pontine gray

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Subpial granular layer

Lateral ventricle

cu

Interpeduncular fossa

inal orh Entcortex



ia

Oculomotor nerve fibers?

Meyer's loop (visual radiation)

r su m

Hilus nu e ay l la a r l r r l a ye la St ratu m d St r a t u m ra

r ye

Subgranular zone

Fimbria

Lateral migratory stream

S

i c u la raf

Pa


Zona incerta

Ventral tegmental area

Internal capsule

e

gyrus te

Oculomotor nuclear complex (III)

Ventral posteromedial nucleus

G r aecu M ol

Ammon's ho r

eus

R ULA TRIC IVEN LEX PER CO M P

Presubic ul

le nc du pe

ulum bic Su

r n u cl

P

CA1

HIPPOCAMPUS um


CA3


Habenulointerpeduncular tract

Interpeduncular nucleus

al br re


Subgranular zone

Red nucleus

Ventroposterolateral nucleus


Medial longitudinal fasciculus

MIDBRAIN

Ce

CA3

Third ventricle

a sc

M

X

SUBTHALAMUS

Pa


psule nal ca Exter en Putam

CO LE

ra

AL

Medial habenular nucleus

Tegmentum

n

Layer I

Ventral lateral nucleus

rus Insular gy

TR


EX PL M CO


Dorsomedial Nucleus

Choroid plexus

CEN

BELT


THALAMUS L RA NT VE

RETIC ULA R

BASAL GANGLIA

Cortical plate

Stria medullaris

DORSAL COMPLEX

Lateral habenular nucleus


White matter

Stria terminalis

Dorsolateral nucleus

Callosal sling Lateral fissure


Py r


Cingulate gyrus

Paracentral lobule

ar

Paracentral stratified transitional field




Middle cerebellar peduncle Pontocerebellar fibers Pontocerebellar fibers (decussation)

50


See the entire section in Plate 12 12.

White lines running through this section are artifacts of histological processing.

51

PLATE 38B Callosal glioepithelium

Fornix Fornical glioepithelium

Medial lemniscus

lu m

cu

Pre sub icu l


Parasubiculum

Red nucleus

Superior cerebellar peduncle Interpeduncular nucleus

Oculomotor nerve fibers?

Subgranular zone


ni gr a

Tegmentum

um

S

ub



Stratum am Pyr id

Hilus ar l a ye a r ye r la

n tra t u m lac u t u ia S tr a t u m rad

S

M CA i PO

S PU


Stria terminalis


s ien er or al lay

Subgranular zone

Oculomotor nuclear complex

ia

Optic tract

Central gray

Suprageniculate nucleus

Internal capsule



ec u l a r

MIDBRAIN


l G r a nu c u l le Mo

gyrus te


Mesencephalic glioepithelium/ependyma

le nc du pe al br re Ce

Den ta

Ammon's ho r


Cerebral aqueduct

White matter

sule

CENTRAL COMPLEX

rus Insular gy

BELT

Subcommissural organ

Pretectum

CO M PL EX

Cortical plate

ap nal c Exter

THALAMUS

n Putame

RETIC ULA R

VE NT RA L

CA3

IP H

Vental posterolateral nucleus


POSTERIOR COMPLEX


Layer I Pulvinar


CA1

Callosal sling

POSTERIOR COMPLEX


n

Stria terminalis

Reticular nucleus







Choroid plexus

Pa ra br ac hi al Su nu bs cl ta eu nt s

Lateral fissure

Lateral ventricle

r o m s um -m o l



Cingulate gyrus


e


Lateral ventricle


Alvear glioepithelium Entorhinal cortex

PONS Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field

Pontine gray

Temporal lobe Middle cerebellar peduncle Transpontine corticofugal tract (thick longitudinal bundles) Reticular tegmental nucleus Pontocerebellar fibers (thin transverse bundles)

Pontocerebellar fibers (decussation)


52



53

PLATE 39B



Callosal glioepithelium Lateral ventricle



POSTERIOR COMPLEX

CSubic

gr

De e

p

e

ia

Pr e te c tu rfi m c Su pe

M id dl

Cerebral aqueduct




Parasubiculum

Tegmentum



Oculomotor nucleus (III)

Reticular formation

te

Central tegmental tract

Granular layer Hilus Molecular layer

Subgranular zone

Stratum lacunosummoleculare

Medial longitudinal fasciculus Superior cerebellar peduncle


Fimbria/fornix

Brachium of the inferior colliculus Lateral lemniscus


Hippocampus:

Stratum radiatum Pyramidal layer

M

le al e di

Stratum oriens

m

Temporal lobe

Cerebral peduncle

Pontocerebellar fibers (thin transverse bundles)


PONS

Subpial granular layer Middle cerebellar peduncle

Nerve V

In


Mesencephalic nucleus of V


Pontine gray


ule ps ca

us

PO

P M A ul

Pos t er ior

Op tic ne r id dl ew

sc

H

IP

us

er Subcommissural lay y organ a er gr ay l ay Central gray

M

ni

CA1

r ntate g y

Presub icu

Tectum

Raphe nuclear complex

De

US

um

roid plex us m A mon' s

Cho

Subgranular zone

rn CA3 ho

l

a gr

Superior colliculus

er l ay ve er y la e te ur hi iss m m Co

Glioepithelium Stem cells of choroid plexus Fornical glioepithelium

r aye yl

Stria terminalis


MIDBRAIN

m lu

Lateral ventricle

Pulvinar

leus lar nuc


Callosal sling

THALAMUS

RETICULAR BELT



ic u Ret


x rni Fo

rn al

Choroid plexus

Transpontine corticofugal tract (thick longitudinal bundles)


54

PLATE 40A GW37 Coronal CR 350 mm, Y217-65, Level 14: Section 1141


55


Callosal glioepithelium Lateral ventricle

Choroid plexus

Fornix


Hippocampal Commissure


Fornical glioepithelium Pulvinar

THALAMUS

bria Fim



Stria terminalis Internal capsule

POSTERIOR COMPLEX

Hippocampus

Central tegmental tract

Mesencephalic nucleus of V

Oculomotor nucleus (III)


Parabigeminal nucleus (ventral)



Cerebral aqueduct Central gray



Tegmentum

Reticular formation

Tectospinal tract Superior cerebellar peduncle (decussation) ed M Reticular tegmental nucleus

Temporal lobe

Cortical plate

ia


PONS

Middle cerebellar peduncle

Lateral ventricle

White matter

ll


Hilus Stratum oriens Pyramidal layer Stratum radiatum Stratum lacunosummoleculare

Subgranular zone

us Lateral lemniscus

O

Inferior colliculus

Nucleus of the lateral lemniscus (dorsal) Parabigeminal nucleus (dorsal)



r ye la

nis c

CA1

Parasubiculum

Superior colliculus

em

HIPPOCAMPUS

Mi dd l

m

u lu

ic

b Su

Brachium of the inferior colliculus

Tectum

er y lay gra

Molecular layer Granular layer

er lay

us

yer ve la ner e

m ulu

e n t ate

r gy

ic pt

Zonal la yer r f e i c p i al g Su ra y

MIDBRAIN

layer hite le w idd layer i te M wh ep De

Presubi c

CA3

D

Ch oro id ple xus Ammon's ho rn

Fornical glioepithelium Subgranular zone

Dee pg ra y


Layer I Pontocerebellar fibers (thin transverse bundles)

Pontine gray

Nerve V



56

PLATE 41A GW37 Coronal CR 350 mm, Y217-65, Level 15: Section 1181


57

PLATE 41B

De

Fim br ia

n

te ta

gyru

Hippocampal Commissure Hippocampus

s

Molecular layer

Subgranular zone

Subgranular zone CA3

S u bic

m ulu

HIPPOCAMPUS

Opt ic


aye rve l r ne yer ray la eg dl layer y a gr p

erficial g Sup

Middle w hit

Tectum

whi te la

r ye

De e

D eep

Cerebral aqueduct

Central nucleus

Central gray

Tegmentum

Nucleus of the lateral lemniscus (ventral)

Dorsal tegmental nucleus

Inferior colliculus

Mesencephalic glioepithelium/ependyma Trochlear nucleus (IV)

Temporal lobe

Medial longitudinal fasciculus Tectospinal tract

Reticular formation

Superior Pontine olive gray

PONS

Nerve V (root, with myelination gliosis)

Central tegmental tract Abducens nucleus (VI)?

CE REB ELLU M

Trigeminal motor nucleus?

Hemisphere

Molecular layer

Medullary layer


Nerve VIII Trapezoid body (intermingled with medial lemniscus)

External germinal layer Granular layer

Medial lemniscus


pe r p e io r c du ere n c be l e ? l la r

An te (H rio I-H r L V) obe


Su


Stratum lacunosummoleculare

Superior colliculus

Mesencephalic nucleus (V)


Parabrachial nucleus

Pyramidal layer Stratum radiatum

Lateral lemniscus


Stratum oriens

Zonal l

MIDBRAIN

Mi d

CA1


Hilus


yer y la r ra aye el

e n

Granular layer

er ay

t a te

s

esubiculum Pr

r u gy

D

Ammon' sh or n

Internal capsule



Lat era l ve ntri cle Ch oro id ple xu s


Inferior olive

MEDULLA

Inferior cerebellar peduncle

Corticospinal (pyramidal) tract


58



59

PLATE 42B Germinal and transitional structures in italics MIDBRAIN

L

at

er

al le

m n iscu

Brachium of

Central gray

Inferior colliculus

s

Frenulum

Nerve IV root and decussation? sc u

Superior medullary velum Mesencephalic glioepithelium/ependyma

s

L nu ater cl e a u l c e re bellar pe dunc s le

ni lem

infe ri

colliculus or

Central nucleus

Tectum

Cerebral aqueduct

External germinal layer Molecular layer

h i al

Isthmus Locus coeruleus

Central gray

Parabrac

Granular layer Medullary layer

C ER CE REBELLUM

or

Mesencephalic nucleus V

ri

pe

PONS

Reticular formation

ule ob xl ple VI) Sim (H

Pontine Middle gray cerebellar peduncle

Nerve VIII root Paramedian lobule? (HVIIB)

ap Tr

id ezo

y bod


Motor nucleus V

Tectospinal Motor tract nucleus VII Central tegmental tract

Choroid plexus

MEDULLA Inferior cerebellar peduncle and spinocerebellar tracts

Corticospinal (pyramidal) tract Arcuate nucleus (medullary)

Prin cip nucl al senso eus ( r V) y

Abducens nucleus VI Raphe nuclear complex

r io

Su


Hemisphere


Cochlear nucleus (dorsal)

emniscus

A

e nt

b

V)

M e d ial l

Primary fissure

o rL

H e(

I-H

Inferior olive

Cochlear nucleus (ventral) Superior olive (periolivary nuclei)

60



61


Vermis

Culmen (IV, V)

External germinal layer

Centralis (III)

Molecular layer Granular layer Medullary layer

Fourth ventricle (lateral recess)

? ule ob l ian ) ed VIIB m ra (H Pa

Flocculus (HX)

Germinal trigone

re Su be p lla eri r p or ed un cle ce

Pontine glioepithelium/ ependyma

Dorsal longitudinal fasciculus

Hypoglossal nucleus (XII) Nucleus of Roller

Spinal tract (V)

MEDULLA Lateral reticular nucleus

Inferior olive

Prepositus nucleus

Hemisphere


Dorsal sensory nucleus (X)

Stem cells of choroid plexus Inferior cerebellar peduncle and spinocerebellar tracts

C E R EB E L L UM

Fourth ventricle

Superior vestibular nucleus Medial vestibular nucleus Inferior vestibular Solitary nucleus nuclear complex

Floccular peduncle

Lingula (I, II)

Solitary tract

Retrofacial nucleus?

Medial longitudinal fasciculus and tectospinal tract

Raphe nuclear complex Medial le mniscus

u le ob l le x V I ) p S im (H

PONS

Spinal nucleus (V)

e ob L ior er t An

Primary fissure

V) H I(H

Middle cerebellar peduncle Cochlear nucleus (ventral)

Paramedian reticular nucleus

Reticular formation Do o li r s a va l a ry cc n u e ss c le o r y us

Corticospinal (pyramidal) tract

Choroid plexus

62



63


Vermis Culmen (IV, V)

C E RE B E L L UM EL

)

V

e ob

Primary fissure

nt A

(H

H I-

Centralis (III)

L or

i er

External germinal layer Molecular layer

Fastigial nucleus

Germinal trigone

p

uc

Nodulus (X)

nt a te nu

ccu

c le

la r

Germinal trigone

us

pe

Bi ve l (H obu ntr VI le al II )

ian lobule dian med Para Parame (HVIIB)

le

Ansiform lobule Crus II (HVIIA)

nc

Uvula (IX)

Paraflocculus (HIX)


du

Ansiform lobule Crus I (HVIIA)

Hemisphere

De

D

ee

N

Medullary layer

F lo

e ul b lo ) x I e pl HV m ( Si

i le

Granular layer

In te r n u c p o situ le u s s

Flocculus (HX)

Choroid plexus Medial vestibular Fourth ventricle nucleus Solitary nuclear Medullary complex Cuneate glioepithelium/ Dorsal nucleus ependyma longitudinal fasciculus Nucleus ambiguus Paramedian reticular nucleus

Spinal tract (V) Reticular formation

Spinal nucleus (V) Spinocerebellar tracts (dorsal and ventral)


MEDULLA Raphe nuclear complex Pyramidal decussation

Accessory nucleus (XI) Ventral corticospinal tract?

64


See the low magnification view in Plate 19.

65


Vermis Declive (VI)

Primary fissure

V) I-H H ( obe rL o i ter An

ule b o x l I) e l p V im (H


le uc N p ee

Uvula (IX)

Paraflocculus (HIX)

tral Biven le lobu I) I (HVI

Medullary layer

De n

ta

te n

s

Ansiform lobule Crus II (HVIIA) ule lob n a ) edi am HVIIB r a ( P

Granular layer

uc leu

D


Molecular layer

Culmen (IV, V)

Pyramis (VIII)

i

S

C ER EBE LL E RE EL LUM

Hemisphere

66


Level 21: Section 1711

See the low magnification views of both sections in Plate 20.

67


CE REB E L L U M

Declive (VI)

le obu l x ple I) Sim (HV

External germinal layer Molecular layer Granular layer Medullary layer

Folium (VIIa) Tuber (VIIb)



Pyramis (VIII)

e ul b o l an B) i ed I m HVI a r ( Pa

Hemisphere

Vermis e ul b lo al III) r t en (HV v Bi

le obuA) l m ifor (HVII s n A us I Cr

le obu A) l rm II sifoII (HV n A us Cr le obu l n ia medVIIB) a r Pa (H le lobu l a r II) ent Biv (HVI

Hemisphere

68

PART PART III: III:

GW37 GW37 SAGITTAL SAGITTAL

This specimen is case number B-180-61 (Perinatal RPSL) in the Yakovlev Collection. A female infant survived for one hour after birth. Death occurred because a hyaline membrane obstructed the airway to the lungs. The brain was cut in the sagittal plane in 35-µm thick sections and is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). There is no photograph of this brain before it was embedded and cut, so the photograph of another GW37 brain that Larroche published in 1966 (Figure 3) is used to show medial surface features. Photographs of 8 different Nissl-stained sections (Levels 1-8) are shown at low magnification in Plates 47-54. The core of the brain and the cerebellum are shown at high magnification in companion Plates 55AB-62AB for Levels 1-8. Very high magnification views of different regions of the cerebellar cortex are shown in Plates 63 and 64. Because the section numbers decrease from Level 1 (most medial) to Level 8 (most lateral), they are from the left side of the brain; the right side has higher section numbers proceeding medial to lateral. The cutting plane of this brain is nearly parallel to the midline. However, the posterior part of each section is angled more toward the right than the anterior part. For example, in Level 1 (Plate 47) part of the paraflocculus from the right side of the brain is beneath the cerebellar vermis. The paraflocculus is very small in Level 2 (Plate 48) and the left paraflocculus appears in Level 3

(Plate 49). The sections chosen for illustration are spaced closer together near the midline to show small structures in the diencephalon, midbrain, pons, and medulla. Y180-61 contains the same group of immature structures that are in the other GW37 brains. In the cortical regions of the telencephalon, remnants of the germinal matrices are present in all lobes of the cerebral cortex where the neuroepithelium/subventricular zone may still be generating neocortical interneurons. Remnants of migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields, thin in the occipital lobe, and thicker in the frontal, parietal and temporal lobes. Indeed, thickness variations can be used as identifying criteria for designating a particular cortical germinal matrix as occipital or otherwise. Many neurons, glia, and their mitotic precursor cells are still migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Within the lateral parts of the cerebral cortex, streams of neurons and glia are still in the lateral migratory stream that percolates through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus. These cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid

complex. In the basal ganglia, there is a prominent neuroepithelium/ subventricular zone overlying the striatum and nucleus accumbens where neurons are probably still being generated. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Other structures in the telencephalon, such as the septum, fornix, and Ammon’s horn part of the hippocampus, have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle. Most of the structures in the diencephalon appear to be settled and are maturing, and the third ventricle is lined by a thin glioepithelium/ ependyma. In the midbrain and anterior pons, there is a slightly thicker and more convoluted glioepithelium/ependyma lining the posterior cerebral aqueduct and anterior fourth ventricle. The posterior pons and entire medulla have a thin glioepithelium/ependyma lining the rest of the fourth ventricle. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is still producing basket, stellate, and granule cells. The germinal trigone is still visible at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia may still be originating here.

69

Cen t

P

Cuneus

Calca ri

i

Ci

Lingula

it a

ip cc

M e dia l

o

LA

H

DUL ME

em

is p h e r e

Cerebellar vermis

PONS

i

OCCIPITAL LOBE

OBE

cc

us sulc l a pit

s

PO

LL

-o iet o r s a

tum Tec IN BRA MID tum men Teg

T EM

RA

r

cu sul ne

DIENCEPHALON

Hypothalamus

Ma

cus

l enia area spl tro Re ium len

Thalamus

tum

Gyrus rectus

PA

lcus l su na

Precuneus

Genu Subcallosal area

n

gi

ulate su l

ce

l gyr

s gyru e t ula m s callosu ng u p r Co ix Forn

t Pos

yrus lg a tr

Sp

gulate su Cin lcu

Su pe ri

s

C i ng

Sep

FRONTAL LO BE

us yr g s l sulc u ta ate l n u o g fr Cin

l sulcus ra

AL ET RI BE LO

or

us yr

PARACEN TRA L LO Precentr BU al LE g

Ce

re

ll be

ar

Spinal cord Figure 3. Midline sagittal view of a GW37 brain with major structures in the cerebral hemispheres and brainstem labeled. (This is part of Figure 2-9 on page 27 in B. A. Curtis, S. Jacobson, and E. M. Marcus (1972) An Introduction to the Neurosciences, Philadelphia: W. B. Saunders. The photograph was originally published by J. C. Larroche (1966) The development of the central nervous system during intrauterine life. In: Human Development, F. Falkner (ed.), Philadelphia: W. B. Saunders, page 259.)

70

PLATE 47 GW37 Sagittal CR 310 mm Y180-61 Level 1: Section 961

Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5

6 7 8 9

Callosal sling Strionuclear glioepithelium Diencephalic glioepithelium/ependyma Mesencephalic glioepithelium/ependyma Pontine glioepithelium/ependyma

Medullary glioepithelium/ependyma Germinal trigone (cerebellum) External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 55A and B. White matter Cortical plate

Central sulcus Postcentral gyrus Cingulate sulcus (marginal part)

Precentral gyrus

Layer I

9 Superior frontal gyrus

Frontal lobe

Cingulate sulcus

tal rie Pa lobe

Cingu

Paracentral lobule

late gy

Fornix

Subcallosal area

3

3

Preoptic area

Thalamus

Third ventricle

Se

2

Hypothalamus

M id br ai n

Te gm en tu m

Optic nerve (II) and chiasm Cerebral peduncle Oculomotor nerve (III) Corticofugal tract Damaged areas in section

Cerebral aqueduct

Pons

4

5

Cingulate sulcus Fourth ventricle

um ct Te

Inferior rostral gyrus?

m

Genu

al ter le Lantric ve

ptu

1

Corp u s ca l losum m iu len Sp

Superior rostral gyrus?

rus

Precuneus

Cerebellum (vermis)

7 6

Medulla

8

Paraflocculus (from right side of brain)

71



Callosal sling Strionuclear glioepithelium Mesencephalic glioepithelium/ependyma Pontine glioepithelium/ependyma

5 6 7 8

Medullary glioepithelium/ependyma Germinal trigone External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 56A and B. White matter Cortical plate

Precentral gyrus Precentral sulcus?

Layer I

8 Superior frontal gyrus

Frontal lobe


Cingulate sulcus

Cingu

tal rie Pa lobe

Paracentral lobule

late gy rus

Genu

Gyrus rectus

2

Thalamus

Subcallosal area

Hypothalamus

Preoptic area Optic nerve (II) and chiasm Cerebral peduncle Oculomotor nerve (III)

See high magnification views of the cerebellum in Plates 63 and 64.


Corticofugal tract

M id Te br 3 gm en ai tu m n

um ct Te

Orbital gyrus?

l era Lat tricle n ve m ptu Se

Corpus c allosum m iu len Sp

1

Superior rostral gyrus?

Fornix

Precuneus

Cingulate sulcus Fourth ventricle

Cerebellum (vermis)

4

7

6

Pons

5 Medulla

Paraflocculus

72



6 7 8 9 10

Rostral migratory stream Rostral migratory stream (source area) Callosal glioepithelium Accumbent neuroepithelium and subventricular zone (infiltrated by the rostral migratory stream) Anteromedial striatal neuroepithelium and subventricular zone

Anterolateral striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Pontine and medullary glioepithelium/ependyma External germinal layer (cerebellum) Subpial granular layer (cortical)


Precentral gyrus

Precentral sulcus

Central sulcus Postcentral gyrus


10

e lob l a t on Fr

Cingulate

3

White matter

C

pus callosum

ntricle al ve

6

5

2

Gyrus rectus? Olfactory bulb and peduncle

1

Cing ulu

Thalamus

Nucleus 7 accumbens

3

Subthalamus

Substantia innominata Lateral hypothalamus Optic tract Internal capsule Cerebral peduncle


Midbrain

Te gm en tu m

Pons

Precuneus

Pa rie ta ll ob e

Retrosplenial area

tum Tec

Orbital gyrus?

5 4

gyrus

Fornix

Basal ganglia

Layer I

Cingulate sulcus

m m iu len Sp

er Lat

Cortical plate


or

Paracentral lobule

Postcentral sulcus Superior parietal lobule

8

Cerebellum (vermis)

Medulla

al ipit Occ obe l

9

Cerebellum (hemisphere) Paraflocculus (from left side of brain) Fourth ventricle (lateral recess)

73

PLATE 50


Rostral migratory stream Frontal stratified transitional field (intermingled with the source of the rostral migratory stream) Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium

6 7 8 9 10

GW37 Sagittal CR 310 mm Y180-61 Level 4: Section 781

Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)


Precentral gyrus


Middle frontal gyrus?


Superior frontal gyrus?

Frontal lobe

3

White matter

Co

Paracentral lobule

rpus call o

6

Layer I

al rn e te u l In a p s c

Uneven stain due to variation in section thickness

2

Orbital gyrus

1

capsule

Optic tract

Internal

External capsule

m

7

Basal ganglia

Cortical plate

su

Lateral ventricle

8

4

10 Cingulate sulcus

5

Thalamus

Subthalamus

Olfactory bulb

Angular gyrus?

Fornix

4

Par i lob etal e

Precuneus

ParietoParietooccipital occipital sulcus sulcus

um

eni Spl

Retrosplenial area

Calcarine fissure Primary visual cortex

Cerebellum (hemisphere)


Amygdala Ventral hippocampus


Midbrain tegmentum Trigeminal nerve (V) Cerebral peduncle

Occipital lobe

Cuneus

9 Cerebellar deep nuclei Inferior cerebellar peduncle Middle cerebellar peduncle

74



Callosal glioepithelium Fornical glioepithelium Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical)

6 7 8 9 10 11

Amygdaloid glioepithelium/ependyma Anterolateral striatal neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)


Central sulcus

Precentral gyrus

Postcentral gyrus

White matter



1


C o rp

Frontal lobe

B

External capsule

a as

Orbital gyrus


n

7 Internal capsule


Primary olfactory cortex (Piriform)

11

a lg

ia gl

5 Amygdala

9

us ca

8

llosu

2

Thalamus Subthalamus

Optic tract

6

3 4

Ventral hippocampus Midbrain tegmentum Cerebral peduncle

Angular gyrus

Paracentral lobule

Par i lob etal e m

Supramarginal gyrus

1

Parietooccipital sulcus Lateral ventricle

Fornix

Splenium Retrosplenial area

Cuneus

Occipital lobe Calcarine fissure

Dorsal hippocampus Cerebellum (hemisphere)

10

75


Remnants of the germinal matrix, migratory streams, and transitional fields Fornical glioepithelium Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical)

6 7 8 9 10

Amygdaloid glioepithelium/ependyma Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)


Precentral gyrus




White matter Cortical plate

Angular gyrus

Layer I

Lateral fissure

Co

Frontal lobe

5

rpus

callosu


Fornix

3

Amygdala Ventral hippocampus Damaged areas in section

1

Par i lob etal e

Cuneus

Dorsal hippocampus

4

Supramarginal gyrus Parietooccipital sulcus

2

Thalamus

6 Orbital gyri Primary olfactory cortex (Piriform)

m

Lateral ventricle

7 8

lia ang g l Inte sa rnal capsule

Insular gyrus

Paracentral lobule

10


Ba


Ex Clau ter str n a um lc ap su le

1 2 3 4 5

Occipital lobe Occipital gyri Calcarine fissure Fusiform gyrus?

Optic tract Cerebellum (hemisphere)

9


Entorhinal cortex (in parahippocampal gyrus)

76



Callosal glioepithelium Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Alvear glioepithelium Subgranular zone (dentate)

6 7 8 9 10 11

Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)


Precentral gyrus


Precentral sulcus

Postcentral sulcus


Angular gyrus


Paracentral lobule

White matter

Layer I

Frontal lobe Claustrum

Basal ganglia

External capsule Lateral fissure

Orbital gyri

Insular gyrus

6 11

Amygdala


7


e ul ps

Fornix

Thalamus

Substantia innominata Lateral ventricle

8 9

Internal ca

Cortical plate

Ventral hippocampus

4 E n tor

hina

5 x rte l co

Supramarginal gyrus

Par i lob etal e

1

Corpus callosum


Lateral ventricle

2

Cuneus

Dorsal hippocampus

Lingula

Occipital lobe

Occipital gyri

Calcarine fissure Cerebellum (hemisphere) Parahippocampal gyrus

Fusiform gyrus?

10

77

PLATE 54 Remnants of the germinal matrix, migratory streams, and transitional fields Amygdaloid glioepithelium/ependyma Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)


Precentral gyrus


Precentral sulcus

Postcentral sulcus Angular gyrus

White matter Cortical plate Layer I Middle frontal gyrus

al nt o Fr

e lob

1

External capsule Claustrum Lateral fissure


s al Ba

Hi

11

c po

am

pu

s

5

lob e


2

Lateral ventricle

su le

p

Occipital gyri

Occipital lobe

Cuneus Lingula

4

7Entor3hinal cortex

Superior temporal gyrus?


In

lc na ter

Pa rie tal

8

ap

yr

6

Am yg da la

Orbital gyri

9

ga ng lia

us


Supramarginal gyrus

Paracentral lobule

rg


Lateral migratory stream (cortical)

la

3 4 5

6 7 8 9 10 11

su

2

Parietal neuroepithelium, subventricular zone, and stratified transitional field Occipital neuroepithelium, subventricular zone, and stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Alvear glioepithelium

In

1


Cerebellum (hemisphere) Parahippocampal gyrus

Calcarine fissure

10

78

PLATE 55A GW37 Sagittal CR 310 mm Y180-61 Level 1: Section 961


79

PLATE 55B Cingulate gyrus

Cerebellar fissures

Induseum griseum

sum allo c ) s rpu ody Co (b

La

al te r

c le

HYPOTHALAMUS Mammillothalamic tract

Dorsomedial nucleus



Trochlear nucleus (IV)?



M

TEGMENTUM

Trochlear nerve bundles?

5

ed

ia

Reticular formation

PONS

Pontine gray

A

Lingula I, II

6

Superior medullary velum

Dorsal tegmental Fourth nucleus ventricle ul

6

p he

8

E

nu

Reticular formation

C

Prepyramidal fissure (separates tuber and pyramis)

D

Secondary fissure (separates central and posterior lobes)

E

Posterolateral fissure (separates posterior and inferior lobes)

CER EB E B

7 Reticular formation

Choroid plexus

Dorsal raphe nuclei

M E DU LL L LA A

Transpontine corticofugal tract Hypoglossal (thick longitudinal bundles) nucleus (XII) *Arcuate nucleus (medulla) Inferior *Cells may be entering this nucleus Olive Medial lemniscus (decussation) via the Raphe migration. Corticofugal tract

E

POSTERIOR LOBE

D

L

Declive VI

CENTRAL LOBE C

D Uvula IX

L

E R M I S B

Fastigial nucleus

INFERIOR LOBE Nodulus X

us

clea r c o m p l e x


BE LO R Centralis RIO III TE N V A

Primary fissure (separates anterior and central lobes)

A

Inferior colliculus


iscus

External germinal layer (cerebellum)

Culmen IV, V

TECTUM

l lemn

Germinal trigone (cerebellum)

lu s

Media

Medullary glioepithelium/ependyma

Red nucleus

9

Ceerebral aqueduct

Ra


5 MIDBR AI N M IDBRAI

Third ventricle

licu

ic

Thalamic glioepithelium/ependyma

Central gray

col

sc

Glioepithelium (optic nerve and chiasm)

io r

a nal f

Preoptic glioepithelium/ependyma

per

udi



Su


git

Oculomotor nerve Ventral tegmental area

Remnants of the germinal matrix

Pontine glioepithelium/ependyma

Cerebral peduncle

x ple

4

on

3

Mammillary body Arcuate nucleus

lc o mplex

ll

2

Third ventricle (preoptic recess)

4

ricular com


PREOPTIC AREA

Lamina terminalis

1 2 3 4 5 6 7 8 9

ent

Fields of Forel



riv

ra


B

U

M

Subcallosal area

1

Pe

TH ALA MUS

nt

e

Fornix (postcommissural)

Medial septal nucleus


4

Dorsomedial nucleus

C

S E PT UM

Suprachiasmatic nucleus Optic nerve and chiasm

Choroid plexus

Anterior commissure

Medial habenular nucleus Habenulointerpeduncular tract Posterior commissure

Dor sal compl com plex ex

Third ventricle

l) l ix ra p ta rn ssu Fo mi l se u s a r m te le co La nuc re

Corpus callosum (rostrum)

Stria medullaris

ix rn o F

r rio x te ple Anom c

(p

ve

i n tr

Cave of the septum

Preculminate fissure (separates centralis and culmen)

Folium VIIa Tuber VIIb )

C

e le her bumisp o l he

Pyramis VIII

n ia to edtuber m ra om Pads fr en

xt

(e

E H E M I S P H

E

Hippoc a commis mpal sure

A

R

Paraflocculus

(tonsil, extends from uvula to hemisphere)

9 Prepositus nucleus Dorsal motor nucleus (X) Gracile nucleus Gracile fasciculus Medial longitudinal fascuculus and tectospinal tract

80

PLATE 56A GW37 GW37 Sagittal Sagittal CR CR 310 310 mm mm Y180-61 Y180-61 Level Level 2: 2: Section Section 941 941

Area of high magnification in Plate 63 See the entire section in Plate 48.

Area of high magnification in Plate 64

81

PLATE 56B



HYPOTHALAMUS Sexually dimorphic nucleus

Dorsomedial nucleus

Red nucleus

TEGMENTUM

D teg ors a nu ment l cle al us


Reticular formation

Substantia nigra

PONS

Cerebral peduncle

Fornix


Fourth ventricle


Pontine gray

POSTERIOR LOBE

E

Uvula IX

INFERIOR LOBE Nodulus X

Reticular formation M

1 2 3 4 5 6 7 8

Callosal sling Fornical glioepithelium Strionuclear glioepithelium

6 Gracilis nucleus

In fe pr rior MEDU DUL LLA LA nu inci Oli ME cle pa ve us l

*Arcuate nucleus (medulla) Medial accessory olive Pyramid (corticospinal tract) Pyramidal decussation Medial longitudinal fascuculus and tectospinal tract

*Cells may be entering this nucleus via the Raphe migration.


Gracile fasciculus Dorsal motor nucleus (X) Hypoglossal nucleus (XII)

Cerebellar fissures A


B


C


D


E


Medullary glioepithelium/ependyma Germinal trigone (cerebellum)

M

S

Choroid plexus

Mesencephalic glioepithelium/ependyma Pontine glioepithelium/ependyma

H E

I

Paraflocculus

Area postrema?

s


D


cu


C



Gyrus rectus

Diagonal band of Broca (vertical limb) Substantia innominata/ olfactory tubercle

E

Tuber VIIb

Pyramis VIII

D


n is

Oculomotor nerve (III)

LO BE


5

LOBE

7

Lingula I, II


Mammillary body

A

Trochlear nerve bundles?


4


Centralis III

Inferior colliculus

le m ial ed

PREOPTIC AREA

TECTUM

Reticular formation

Fields of Forel


M IDBR AIN ?


Fornix

Central gray

V E R M I S B C CENTRAL

E R E

le x Ante ro nucl medial eus

Centromedian n.

A

8

Folium VIIa

(ex Pa ten ra ds f me rom di tub an l er t ob o h ule em isp her e)

mp

Superior colliculus hite layer Deep w

B

Culmen IV, V

8

Declive VI

H

3

Medial preoptic nucleus

Subcallosal area

co

In te rp nu edu cle nc us ula r

1

al

Periventricular complex

x

Prec om m is s ur Late al f ral orn se p t al i nuc leu s

2

tr

CEREBELLUM


Pr ete ctu m

ter od Str ors i al a m nu cle ed us ul

(c Fo rn i

x

Large island of Calleja

Foramen of Monro

THA LA MU S

n

Anterior complex

2

Anterior commissure Nucleus accumbens

te nu rove c le n t us ral

Dorsomedial nucleus

Ce

Choroid plexus

Dorsal complex

Central lateral nucleus

An

An

n)

ol

um

Lateral ventricle

r is la

3

nuloHabeduncular pe inter tract

um los l a sc ) rpu(body o C


A N TE R IO R

Cave of the septum

Cingulate gyrus


P

Induseum griseum

82



83

PLATE 57B

3 6

7 Stria terminalis

8

e th of lis s u a cle in nu term d Be stria

Caudate nucleus (head)

6

Anterior limb


Internal capsule


3

2

5

Subthalamic nucleus

Lateral hypothalamus

A

Inferior colliculus

MI D BR A IN

Reti cula r for mat ion

TEGMENTUM Substantia Ce reb nigra ra lp ed un cle

Pontocerebellar fibers

Dorsal nucleus of lat. lemniscus

Lateral lemniscus

Centralis III

A

PONS

Pontine gray


Motor nucleus (V)?

Motor nucleus (VII)

B

Interpositus nucleus

10 Nodulus (remnant)

Fourth ventricle (lateral recess) Uvula (remnant)

C

l ra nt le e v u Bi lob


H E 11

ME DUL LA ar

n io at rm fo

Cuneate nucleus

Spinal nucleus (V)

Cuneate fasciculus

C

Pyramis VIII

Paraflocculus

9

Tuber VIIb

CENTRAL LOBE

Flocculus

Choroid plexus

ul

Anteromedial striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Pontine and medullary glioepithelium/ependyma Germinal trigone (cerebellum) External germinal layer (cerebellum)

Folium VIIa

Floccular peduncle


Inferior olive

Declive VI

B

OBE

tic

Remnants of the germinal matrix, migratory streams, and transitional fields 6 7 8 9 Accumbent neuroepithelium and subventricular zone 10 5 (infiltrated by the rostral migratory stream) 11

C

V E R MI S

Parabrachial nucleus? Superior cerebellar peduncle Principal sensory nucleus (V)?

Nucleus ambiguus

1 2 Rostral migratory stream (source area) 3 Callosal glioepithelium 4 Fornical glioepithelium


L RIOR ANTE

Ventral nucleus of lat. lemniscus

Middle cerebellar peduncle (roots)


B

Culmen IV, V

Brachium of inferior colliculus

Optic tract Supraoptic nucleus Magnocellular preoptic nucleus Olfactory tubercle Diagonal band of Broca (vertical limb)

Olfactory peduncle

Superior colliculus

TECTUM

For el


CEREBELLUM

m tu tec e Pr

Optic nerve layer

A

Re

Olfactory bulb


us sc ni

Subcallosal area

Pulvinar

em ll ia ed

1

Lateral preoptic area

le us


Fiel ds o f

Ventral posterolateral nucleus

THA LAM U S uc


M


Nucleus accumbens

Dorsomedial nucleus

ln

Ventral anterior Anteroventral nucleus nucleus

8

6


later a tral Cen

7

Cerebellar fissures

E R E

8

Fornix

H


4

Pa ra lob med ul ian e

Lateral ventricle

P

3

M

I

S

84



85

PLATE 58B

Parietal lobe Cingulate sulcus

Latera l ventr icle

7


8 Fornix

nucleus

US

Zona incerta

MIDBRAIN TEGMENTUM Substantia nigra

H Nerve V root (premyelination gliosis)

3 Frontal stratified transitional field 4 Callosal glioepithelium 5 Fornical glioepithelium

7

Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone

8 Strionuclear glioepithelium 9 Germinal trigone (cerebellum) 10 External germinal layer (cerebellum)

Dorsal cochlear nucleus

le cerebe Midd

la

e Pari

Primary fissure

ISPHERE M E

cle un ed p r

Simplex lobule (HVI)

Dentate nucleus

Ventral cochlear nucleus

Choroid plexus Nerve VIII root?

Floccular peduncle

Occipital lobe


be r lo o i er V) A n t( H I - H

Cerebral peduncle

c to-o



llar pe

2

Frontal stratified transitional field (intermingled with the source of the rostral migratory stream)


u tal s cipi

9

Paraflocculus (tonsil)(HIX)

H E

M

I

S

Paramedian lobule (HVIIB)

bule tral lo B i v e nH V I I I ) (

C E L U L R E B E

Calcarine fissure

si Cr f u (H orm s I V l I II ob A u ) le

AL Subthalamic AM

lcus

Fasciola cinereum


SU BT H

Remnants of the germinal matrix, migratory streams, and transitional fields 6

Pulvinar

E R E

ucl eu s

TH A LA M U S

Nerve V

1 Rostral migratory stream

Precuneus Corpus callosum (splenium)

an

1

5

le

E nt or cort hinal ex

eus

l

Islands of Calleja

ucl

be

Olfactory bulb


ln

I u s ob ru l ) C rm IIA fo si (HV

Ventral hippocampus

era

an

Amygdala

la t

Choroid plexus

ere

Optic tract

rso

Inferio rc

Internal capsule


Orbital gyrus


al n tr ove s te r le u An nuc

1

2

Olfactory tubercle



teral nu cle l la us tra

BASAL BA S AL GAN GA NGL G LII A

Nucleus accumbens

Reticular n

Internal capsule

G (e x lo b te r u s p na al l s e lid gm us en Gl t) ob (in u s p a s e g te r llid m e nal us n t)

External ca psul e

Anter ior lim b

Putamen

b im

Do

e ncl du

ste Po

ri

l or

Cen

Stria terminalis

Angular gyrus?

4

H

6

Corp us cal lo s u m (b o d y )

P

3

10

M

86



87

PLATE 59B

9

2

Stria terminalis

Fornix

b im r ls o i r ste u Po nu cle

4

eu s

Basal nucleus

us

11

Anterior cortical nucle


Accessory basal nucleus

Lateral ventricle

1 2 3 4 5

6

3

4

Dentate gyrus

VENTRAL HIPPOCAMPUS Subiculum in a orh E n t o rtex c

L B E A

l

Remnants of the germinal matrix, migratory streams, and transitional fields Callosal glioepithelium 6 Amygdaloid glioepithelium/ependyma 7 Anterolateral striatal neuroepithelium and subventricular zone Fornical glioepithelium 8 Anteromedial striatal neuroepithelium and subventricular zone Alvear glioepithelium 9 Strionuclear glioepithelium Subgranular zone (dentate) 10 External germinal layer (cerebellum) Lateral migratory stream (cortical) 11 Subpial granular layer (cortical)

o l ) V

b

IS

e


RE E PH Dentate nucleus

H

Ammon's horn

6

AMYGDALA

Optic tract


r o H i r I e t ( H n

C

Anterior amygdaloid area

nucl

Med ial

R

Cerebral peduncle


Orbital gyrus

Substantia MIDBRAIN nigra TEGMENTUM

E




E

Internal capsule

Ventral striatum

5


nucleus

Ansa lenticularis Anterior commissure

a

Primary fissure

M

ob (in u s p a s e g te r llid m e nal us n t)

SUBT HAL AMU Subthalamic S

Entopeduncular nucleus?

Gl

External capsule

Putamen

incert

Occipital lobe

ge Supr n nu iculaacle te us

G (e x lo b te r u s p na al l s e lid gm us en t)

BAS BA S AL AL G GA A NGL N GLII A

Z ona





DORSAL HIPPOCAMPUS

Pulvinar

T HAL AMU S

M

Reticula r

Internal capsule

Anterior limb


Fi m br ia

U

Putamen

Choroid plexus

Pa rie to su -occ lcu ip s ital

8


E

7

1

Lateral ventricle

L

1

) ody m (b u s o l cal pus Cor

le Middpeduncle r a l l e cereb

ule al lob r t n e v I) Bi (HVII

Flocculus? (HX) Choroid plexus

10

88

PLATE 60A GW37 Sagittal CR 310 mm, Y180-61 Level 6: Section 661


89

PLATE 60B


Anter ior lim b dge

Co

al c Str

E

us nucle lar u ic



Me

Anterior commissure

10

cleus Medial nu

Endopiriform Primary nucleus olfactory cortex (piriform)

A

lam lary d ul


i na

Cerebral peduncle

Optic tract

Central nucleus

6 3

Ammon's horn Dentate gyrus

Fimbria

4

Pulvinar


VENTRAL HIPPOCAMPUS

aSupr late u genic leus nuc

lum Subicu

p ita cci o ie to c u s Par sul

Subiculum s ru gy al p m ca po p i h ra Pa

l

Occipital gyrus

Fusiform gyrus? Occipital gyrus

4

6

Primary fissure Presu biculu m

9

e l o b r o ) i t e r I - H V A n H (

Entorhinal cortex

1 2 3 4 5

Fornix

Choroid plexus

DORSAL HIPPOCAMPUS


L s l ra cleu DA ar e t G u cle La al n Y nu c M i l t r A tera lex co p la so com a B

Lateral ventricle

2

1


SUBSTANTIA INNOMINATA Anterior amygdaloid area

Lateral ventricle

T HA L AM US

BAS BA S AL AL G GA A NGL N GLII A

Ventral striatum

7 8

Re t

Putamen

5

Orbital gyrus

Internal capsule

na

la

Stria Post erio r lim terminalis b

iat

um

lc ap su le

u

r st

er xt

gy

ru

C

s

s In u l a r

Lat e

ral

fi ssu

re

ell

bri


rpu s ca llos um (b o dy)

Remnants of the germinal matrix, migratory streams, and transitional fields Callosal glioepithelium 6 Amygdaloid glioepithelium/ependyma Fornical glioepithelium 7 Posterior striatal neuroepithelium and subventricular zone Alvear glioepithelium 8 Strionuclear glioepithelium Subgranular zone (dentate) 9 External germinal layer (cerebellum) Lateral migratory stream (cortical) 10 Subpial granular layer (cortical)

Cr

us

I, an ( H s i fo VI rm IA ) lob

C ERE BELLU M HE MI SP HE RE Flocculus

ule

Crus II ansiform lobule (HVIIA)

90

PLATE 61A GW37 Sagittal CR 310 mm, Y180-61 Level 7: Section 621


91

PLATE 61B

Corona radiata


gy

s

r

p

m

1 Caudate nucleus (tail)

Internal capsule

Stria terminalis

Ins u l a

f r a l

L

a

t

e

e

AMYGDALA tr

9

4

3 s ru gy al p cam po p i rah Pa

5 um icul Sub

10

Primary e fissure o b l r ) i o t e r I - H V n A ( H Crus I, ansiform lobule (HVIIA)

3


1 2 3 4 5

Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Alvear glioepithelium Subgranular zone (dentate)

6 7 8 9 10 11

Fusiform gyrus? Occipital gyrus

Entorhinal cortex


Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma


C E R EBE L LU M HEMISPHER E

P a r a m e d i a n

Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium

tal ipi c c o to- s rie lcu Pa su Occipital gyrus

Ammon's horn

VENTRAL HIPPOCAMPUS

11

Dentate gyrus

Choroid plexus

DORSAL HIPPOCAMPUS


Choroid plexus

lv en ra

te

7

icl

Basolateral nuclear complex

La

Lateral cortical nucleus

Optic tract

Central nucleus

S

Medial nucleus

Anterior amygdaloid area

2

Pulvinar

Fimbria

5

U


Fornix

M

Endopiriform nucleus Primary olfactory cortex (piriform)

s pallidu Globunsternal (i t) segmen

A

ad lr a su Vi


6 Orbital gyrus

Medullary lamina

L

Anterior commissure

Ventral posterolateral nucleus tion ia

Lateral ventricle

Stria terminalis

A

Ventral striatum

9

cleus

H

6

nu lar icu


8

r limb Posterio

T

BA SA S AL L GA G ANG N GLI LI A Un fas cinat cicu e lus

Cor pus call osu m (b ody )

Putamen

r

E

e xt

a lc na

ru

Re t

e

ru

i s s

u r

la C le su

t us

l o b u l e Biventral lobule (HVIII)

Crus II ansiform lobule (HVIIA) ( H V I I B )

92



93

PLATE 62B Frontal lobe

Angular gyrus

l a r u s


e

rn

Claustrum psule al ca

6

7

l te r a o la B a s u c le a r x n p le com

be

1


Putamen


Y AM

l lo

g y r u s

Uncinate fasciculus

11

Supramarginal gyrus

Ex

6

6

Pa rie ta

ral fi ss te ur a e L

t

In


BAS BA S AL GAN GLI A Caudate nucleus (tail)

Internal capsule

Central nucleus

A AL D G

4

Ammon's horn CA1

9

CA3

3

F im b

8 9

CA3 Dentate Ammon's horn gyrus

r ia

CA1

Dentate gyrus

HIPPOCAMPUS

Stria terminalis

2

CA1

4

Choroid plexus Lateral ventricle

5 Cuneus


Calcarine fissure

2

Entorhinal cortex

10

Remnants of the germinal matrix, migratory streams, and transitional fields Parietal neuroepithelium, subventricular zone, 1 and stratified transitional field

2 3

Occipital neuroepithelium, subventricular zone, and stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field

4 Alvear glioepithelium 5 Subgranular zone (dentate)

6 Lateral migratory stream (cortical) 7 Amygdaloid glioepithelium/ependyma striatal neuroepithelium and 8 Posterior subventricular zone

9 Strionuclear glioepithelium 10 External germinal layer (cerebellum) 11 Subpial granular layer (cortical)

CER

Cru

EBE


s I, ans ( H V i fo r m l o LLU IIA) bule M H EMI SPH ERE

Lingula

Occipital lobe

94

PLATE 63 GW37, CR 310 mm, Y180-61 Level 2, Section 941

Germinal trigone

CEREBELLUM, VERMIS, INFERIOR LOBE, LOBULE X: NODULUS (A relatively mature region of the cerebellar cortex)

External germinal layer Molecular layer Purkinje cell layer Granular layer Medullary layer

Choroid plexus

See the entire section in Plate 48. See larger view of the entire cerebellum in Plates 56A and 56B.

95

PLATE 64 GW37, CR 310 mm, Y180-61 Level 2, Section 941 CEREBELLUM, HEMISPHERE, PARAMEDIAN LOBULE (A relatively immature region of the cerebellar cortex)

GW37, CR 310 mm, Y180-61 Level 4, Section 781 CEREBELLUM, HEMISPHERE, CORTEX (very high magnification) Mitotic cells

External germinal layer (proliferative zone) External germinal layer (premigratory zone)

Bloo d

e l ve s s

Molecular layer

Purkinje cell layer

Granular layer (densely packed superficial part)

Granular layer (less densely packed deep part)



96

PART PART IV: IV:

GW37 GW37 HORIZONTAL HORIZONTAL

yr

up r

rf ro

lg

Centra tr l s al g y Post c u s ru

Pre ce

rio rf r Su pe

NTAL LOB E RO

F

P

RA


L LOBE

CIPITAL LO BE OC

M

O

us

ccipital gyri al o t er La

M id d l e t e m poral g y r

BE LO

S

s gyru

ar am g

al fissure La t er rus Superior temporal gy

O r bital gy

Insular gyrus

Angular l gyrus ina

io


a c ul ntr e

s yru

I n f er

TE

The approximate cutting plane of this brain is indicated in Figure 5 (facing page) with lines superimposed on the GW37 brain from the Larroche (1967) series. The anterior part of each section (on the left in all photographs) is slightly dorsal to the posterior part. In terms of the medial-lateral plane of sectioning, the part of each section near the bottom of the page shows structures cut slightly dorsal to those on the other side of the midline. As in all other specimens, the sections chosen for illustration are spaced closer together to show small structures in the diencephalon, midbrain, pons, and medulla. Illustrated sections are spaced farther apart when they contain only large brain structures, such as the cerebral cortex, basal ganglia, and cerebellum. Photographs of 19 different Nissl-stained sections (Levels 1-19) are shown at low magnification in Plates 65-80. The core of the brain and the cerebellum are shown at high magnification in companion Plates 81AB-95AB for Levels 3-19.

al g nt

rus

This specimen is case number B-301-62 (Perinatal RPSL) in the Yakovlev Collection. A male infant was stillborn after a premature separation of the placenta. This brain is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). It was cut in the horizontal plane in 35-µm thick sections. Since there is no available photograph of this brain before it was embedded and cut, a photograph of the lateral view of another GW37 brain that Larroche published in 1967 (Figure 4) is used to show gross anatomical features.

M

d id

n

us

L

s y ru g tal on s yru g tal n o fr le

PARACENTRAL LOBULE PAR IE TA s

Cerebellar hemisphere Spinal cord

Figure 4. Lateral view of a GW37 brain with major structures in the cerebral hemispheres labeled (the same as Figure 1 repeated here for convenience). (From the photographic series of J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

97

GW37 HORIZONTAL SECTION PLANES

1

341

2

441

3

531

4

561

5

631

6

731

7

761

8

801

9

851

10

921

11

981

12

1051

13

1111

14

1161

15

1251

16

1311

17

1331

18

1381

19

1441

LEVEL NUMBER

SECTION NUMBER

Figure 5. Lateral view of the same GW37 brain shown in Figure 4 with the approximate locations and cutting angle of the sections of Y301-62. (From the photographic series of J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

Y301-62 contains several immature structures that are found in the other two GW37 specimens. In the cortical regions of the telencephalon, remnants of the germinal matrices are present in all lobes of the cerebral cortex where the neuroepithelium/subventricular zone may still be generating neocortical interneurons. Remnants of migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields, thin in the occipital lobe, and thicker in the frontal, parietal and temporal lobes. Because of its plane of sectioning, this specimen shows the most complete view of the occipital lobes at GW37. Many neurons, glia, and their mitotic precursor cells are still migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Within the lateral parts of the cerebral cortex, streams of neurons and glia are still in the lateral migratory stream. That stream percolates through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus, and cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a prominent neuroepithelium/ subventricular zone overlying the striatum and nucleus accumbens where neurons are probably still being generated. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Other structures in the telencephalon, such as the septum, fornix, and Ammon’s horn have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle. Most of the structures in the diencephalon appear to be settled and are maturing, and the third ventricle is lined by a thin glioepithelium/ ependyma. In the midbrain and anterior pons, there is a slightly thicker and more convoluted glioepithelium/ependyma lining the posterior cerebral aqueduct and anterior fourth ventricle. The posterior pons and entire medulla have a thin glioepithelium/ependyma lining the rest of the fourth ventricle. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is still producing basket, stellate, and granule cells. The germinal trigone is still visible at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia may still be originating here.

98


GW37 Horizontal CR 320 mm Y301-62 Level 1: Section 341

1 2 3 4

Frontal stratified transitional field Paracentral stratified transitional field Cingulate stratified transitional field Subpial granular layer

Central sulcus

Precentral gyrus

Postcentral gyrus Postcentral sulcus Supramarginal gyrus

Precentral sulcus Middle frontal gyrus

Angular gyrus

Paracentral lobule

2

1


Frontal lobe


Cingulate gyrus

3

Precuneus

4

Cingulate gyrus

1

3

4 2

10 mm


Parietal lobe


4

99

PLATE 66 GW37 Horizontal CR 320 mm Y301-62 Level 2: Section 441


Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Parietal neuroepithelium and subventricular zone Parietal stratified transitional field

6 7 8 9 10 11

Paracentral neuroepithelium and subventricular zone Paracentral stratified transitional field Anterolateral striatal neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Subpial granular layer

Layer I Cortical plate Internal capsule Basal ganglia

2

9

8

1

10

3

White matter

5 11 4

Corpus callosum


Cingulate gyrus Superior frontal gyrus

10 mm

Choroid plexus

Lateral ventricle

Frontal lobe

6


Precuneus

Cingulate gyrus

Paracentral lobule

7

Parietal lobe


Inferior frontal gyrus Angular gyrus

Precentral sulcus Precentral gyrus Central sulcus

Postcentral gyrus

Supramarginal gyrus

100

PLATE 67



7 8 9 10 11 12

Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium

Lateral fissure Postcentral gyrus Central sulcus Precentral gyrus

Supramarginal gyrus Angular gyrus

Precentral sulcus Inferior frontal gyrus

tral acen Par obule l


Frontal lobe Superior frontal gyrus

Cingulum

Co

rp u

I Lateral ventricle

4


10 mm

2

3

6

10 1112 1

5

Occipital lobe

F

6


Precuneus

US M A AL x ni TH or Splenium

Cingulate gyrus


g gan sal a B

5

s callosu m

Parie tal lo be

Insular gyrus

le apsu nal c lia n ter

Genu


Cingulate g. (retrosplenial area)

4 9 7

8

Cuneus

101


Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium

7 8 9 10 11 12

Parietal/temporal neuroepithelium and subventricular zone Parietal/temporal stratified transitional field Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium


Lateral fissure Postcentral gyrus Central sulcus Precentral gyrus Precentral sulcus al centr Para bule o l Inferior frontal gyrus Middle frontal gyrus

Cingulum

3 10 mm

s callo sum

4

Layer I

White matter

Lateral ventricle

Cingulate gyrus


Cortical plate

rp u

B

10

2 1

Supramarginal gyrus?

ia ule gl l c a p s n a ga ern al I n t THALAMUS as Fornix

5 6

Parietal lobe

5

rp u Co

os u all sc

9 7


Precuneus

Lateral ventricle

m

Occipital lobe Cuneus


6 4 11 12

Angular gyrus

s lar gyru

Splenium


Co


Fo rn ix

Frontal lobe


Temporal lobe

Insu

Genu

1 2 3 4 5 6

8

102



7 8 9 10 11 12

Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium

Parietal/temporal neuroepithelium and subventricular zone Parietal/temporal stratified transitional field Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium


Lateral fissure Postcentral gyrus Central sulcus Precentral gyrus Precentral sulcus

Angular gyrus

Lateral ventricle

Corpus callosum


4

3 Layer I Cortical plate

10 mm

White matter

5

6

al rn te In

1

e ul ps ca

Lateral ventricle um os all sc u rp

Fornix

Hippocampus

THALAMUS Third ventricle

10 11 12

2

gyrus

Splenium

Cingulate gyrus

Genu


B

al as

lia ng a g

Parietal lobe

Co

Insular

SEPTUM

Frontal lobe

Temporal lobe

al cen tr Para bule lo

Inferior frontal gyrus Middle frontal gyrus


6 9

Calcarine sulcus

Parieto-occipital sulcus

Occipital lobe

Cingulate gyru s (retrosplenial area)

4

7

8


103

PLATE 70 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5 6 7 8

Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium Occipital neuroepithelium and subventricular zone Occipital stratified transitional field Parietal/temporal neuroepithelium and subventricular zone

9 10 11 12 13 14 15


Parietal/temporal stratified transitional field Alvear glioepithelium Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium


Septal glioepithelium/ependyma

Superior temporal gyrus Angular gyrus?




10 mm Damaged areas in section

ula Ins

Frontal lobe Corpus callosum (rostrum)


Temporal lobe

Lateral fissure

4

3

Lateral ventricle

r gy

21

rus

14 12 13

Parietal lobe

Parieto-occipital sulcus Calcarine sulcus

Fornix

lia ng a lg sa a B

Subcallosal area SEPTUM

Lateral ventricle

Hippocampus

THALAMUS

Bed nuc. of stria terminalis

Third ventricle

Occipital lobe

Habenula Cingulate gyrus (retrosplenial area)

15

4

5 11

10 8

9


6 7

104




8 9 10 11 12 13 14 15

Rostral migratory stream (source area?) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Alvear glioepithelium Subgranular zone (dentate) Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium


Lateral fissure

Temporal lobe


Frontal lobe






10 mm Damaged areas in section

Insula

r gyru

s

Calcarine sulcus

Fornix

terminalis

Subcall os area al SEPTUM

4 1 3 2

Lateral ventricle

Hippocampus lia ng a lg THALAMUS sa Ba Bed nuc. of stria Pretectum

Lateral ventricle

13


14

Third ventricle

15

Occipital lobe


4

11 5 12

10 8

9


6 7

105


Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5 6 7 8

Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone and stratified transitional field Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

9 10 11 12 13 14


15

Accumbent neuroepithelium and subventricular zone (infiltrated by the rostral migratory stream)

Temporal stratified transitional field Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical) Posterior striatal neuroepithelium and subventricular zone




Temporal lobe

Lateral fissure Inferior frontal gyrus Insular

gyrus

Fornix

Middle frontal gyrus ia Basal gangl

Frontal lobe


4

3 Layer I Cortical plate White matter

1

HYPOTHALAMUS

15

MIDBRAIN

13

Occipital lobe


Tectum


Superior colliculus Cerebral aqueduct

5

2

Calcarine sulcus

US AM AL TH

Third ventricle

Subcallosal area PREOPTIC AREA


10 mm

Nucleus accumbens


Lateral ventricle

Hippocampus

12

6

14 11 9

7

10

8

106

PLATE 73 1 2 3 4

Rostral migratory stream (source area)

5

Parahippocampal neuroepithelium, subventricular zone and stratified transitional field

6 7

Occipital neuroepithelium and subventricular zone

Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Fornical glioepithelium

Occipital stratified transitional field

8 9 10 11 12 13 14 15

Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical) Posterior striatal neuroepithelium and subventricular zone Accumbent neuroepithelium and subventricular zone (infiltrated by the rostral migratory stream) External germinal layer (cerebellum)


Lateral fissure Orbital gyrus

Middle frontal gyrus Orbital gyrus?

Frontal lobe

A TI AN TA ST INA B M SU NO IN

Fornix


MIDBRAIN Subcallosal area Third ventricle Tegmentum Tectum PREOPTIC AREA



10 mm

Temporal lobe

US LAM THA

s yru rg ula s n I



Hippocampus

TH S AL UB AMUS



N accuucleus mbe ns


2

1

14

HYPOTHALAMUS

Cerebral aqueduct

4 12

11

Occipital lobe

CEREBELLUM (Vermis) Superior colliculus

15

5

13 10 8

Lateral ventricle


6

9

7

107


5 6

Rostral migratory stream Frontal stratified transitional field Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone and stratified transitional field Occipital neuroepithelium, subventricular zone and stratified transitional field Temporal neuroepithelium and subventricular zone

7 8 9 10 11 12

Temporal stratified transitional field Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical) Posterior striatal neuroepithelium and subventricular zone External germinal layer (cerebellum)




Insular gyrus

Temporal lobe

Hippocampus

Orbital gyri

Lateral fissure

Frontal lobe


Fornix S IN UBS NO TA M NT IN IA AT A

1 2 3 4


Parahippocampal gyrus Olfactory MIDBRAIN Hemisphere tubercle Tegmentum Tectum CEREBELLUM Subcallosal area Third ventricle Vermis


2

10

3

THALAMUS

1

Cerebral aqueduct HYPOTHALAMUS

10 mm


12

Inferior colliculus

4

8


5

9

11

Occipital lobe

6

7

108



1 2


6



7


3


8


4 5


9

Amygdaloid glioepithelium

10






Olfactory peduncle

Gyrus rectus

Interhemispheric fissure Layer I Cortical plate White matter

10 mm

9

Cerebral aqueduct

2

Fusiform

Occipital lobe

Vermis

CEREBELLUM

10

Inferior colliculus

7

3 4

8 6

gy

Hemisphere

MIDBRAIN Tegmentum Third ventricle Tectum HYPOTHALAMUS

1


? rus

Frontal lobe

Hi pp oc am pu s

Lateral fissure

GDA LA


AM Y

Orbital gyri


Temporal lobe

5

109

PLATE 76 Remnants of the germinal matrix, migratory streams, and transitional fields 2


3 4

Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

5 6 7 8 9

Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma External germinal layer (cerebellum)




Temporal lobe Fusiform gyrus?

Lateral fissure Orbital gyrus Gyrus rectus


Optic chiasm

Third ventricle


10 mm

PONS

HYPOTHALAMUS

1

7

Parahippocampal gyrus Hemisphere

Deep nuclei

Olfactory peduncle

Frontal lobe

Hip poc am pus


AM YGD ALA

1


8

6

l i ta cip be c O lo

Vermis CEREBELLUM

9

Fourth ventricle

2

Layer I

53 4


110



1


2


3


4 5 6 7

Alvear glioepithelium Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma External germinal layer (cerebellum)




Temporal lobe AM YGD ALA

Fusiform gyrus? Parahippocampal Hemisphere gyrus Deep nuclei

PONS

Vermis

6

CEREBELLUM

7

Fourth ventricle

5

Hippocampus

4 10 mm

l ipita Occ be lo

2

3

1


111



Parahippocampal/temporal neuroepithelium, subventricular zone and stratified transitional field External germinal layer (cerebellum)



Temporal lobe

Hemisphere Deep nuclei

Parahippocampal gyrus PONS

Vermis

CEREBELLUM

Fourth ventricle

1 10 mm


Temporal lobe


112


GW37 Horizontal, CR 320 mm, Y301-62

1


Level 15: Section 1251 See detail of brain core and cerebellum in Plates 93A and B. Hemisphere

CEREBELLUM

Flocculus ME

Transpontine corticofugal tract Pontine gray

PONS

Hemisphere DU

LL

A

Paraflocculus

Vermis

Fourth ventricle

1

Deep nuclei

Nerve V Middle cerebellar peduncle

10 mm

Level 16: Section 1311 See higher magnification view in Plates 94A and B (left panel). Hemisphere Flocculus Pyramid Pontine gray

CEREBELLUM MEDULLA

PONS

Inferior olive Inferior cerebellar peduncle Middle cerebellar peduncle

10 mm

Cuneate nucleus and fasciculus

1

113




Level 17: Section 1331 Hemisphere

Flocculus Pyramid

CEREBELLUM MEDULLA

Pontine gray

See higher magnification view in Plates 94A and B (right panel).

Gracile nucleus and fasciculus

PONS

Inferior olive Inferior cerebellar peduncle

1


10 mm

Level 18: Section 1381 See higher magnification view in Plates 95A and B (left panel).

Hemisphere Pyramid Medial lemniscus Inferior olive Flocculus

MEDULLA

Gracile nucleus and fasciculus

1

CEREBELLUM 10 mm


Pyramidal decussation Pyramid Inferior olive CEREBELLUM (Hemisphere)

10 mm

MEDULLA

See higher magnification view in Plates 95A and B (right panel).

Cuneate fasciculus Gracile fasciculus

1

114

PLATE 81A GW37 Horizontal CR 320 mm, Y301-62, Level 3: Section 531


115

PLATE 81B Germinal and transitional structures in italics Paracentral lobule Precentral sulcus

Putamen

Cingulum

Late ral v entr icle Corpu s c a llo su m

Cingulate gyrus


Lateral ventricle

Stria terminalis

Choroid plexus

l ra r nt rio s e e V nt leu a uc n

Pulvinar

al ter a l rso us Do nucle

Fo rn ix

Stria terminalis

Caudate (head)

Posterior limb

ule us ps le a c c l u Ventral na r n lateral r te a ucleus n n I l

Anterior limb

l tera al la s r t n Ce nucleu


m lo s u s cal u p r Co Cingulum

Dorsomedial nucleus


Anterodorsal nucleus

Callosal sling

Visual radiation

Caudate (tail)

Claustrum ule al caps Extern

Re ti cu

Frontal lobe

Parietal lobe

Lateral fissure

Insular gyrus

Fornix Interhemispheric fissure

Induseum griseum


Cave of the septum Fornix Fornical glioepithelium


Callosal glioepithelium Frontal neuroepithelium and subventricular zone


DORSAL COMPLEX

RE

EN

TI

TR

DORSAL COMPLEX AL

CU

BASAL GANGLIA

THALAMUS

CO MP

LA

RB


Layer I

LE

X

ELT

Cortical plate

Fornical glioepithelium Stem cells of choroid plexus

White matter

Callosal glioepithelium Parietal neuroepithelium and subventricular zone

Glioepithelium

Putamen Claustrum


Fo rn ix

R IO X ER E ST PL PO OM C

V



Callosal sling R IO X R E TE PL N M A O C

TRAL COMPLEX CEN


Induseum griseum

External capsule

Parietal stratified transitional field


116

PLATE 82A GW37 Horizontal CR 320 mm Y301-62 Level 4: Section 561


117

PLATE 82B Germinal and transitional structures in italics Lateral fissure

Paracentral lobule Precentral

su le l cap a n r x te

mb Posterior li

Putamen

et ic

R

Caudate (head)



Stria medullaris

Fornical glioepithelium R RIO TE PLEX N A M CO

CE

Cingulate gyrus (retrosplenial area) Induseum griseum Interhemispheric fissure Layer I Cortical plate White matter

Callosal sling

NT

ix rn Fo

DO R A L CO RS MP AL CO L E X MP LE VE X NT RA LC OM THALAMUS C PL UL EX AR BE LT

Co

um ll o s a c s rpu



TI


RE


DORSAL COMPLEX

R IO X ER E ST PL PO OM C



PERIVE NTR ICU LAR CO

EX PL M



Dorsomedial nucleus

Cave of the septum

Callosal sling

Lateral ventricle

Pulvinar

Anteroventral nucleus Anteromedial Anterolei nucleus dorsal nucleus nuc r a l Periventricu

Fornix Lateral septal nucleus



Induseum griseum

SEPTUM


Choroid plexus

Stria terminalis

l ra ate s l s o rs leu leu Do nuc l nuc era lat

r r nt io s Ve nter leu a uc n

Stria terminalis

Cingulate gyrus


n

u

s eu l c

Central

Late Cor ral v pus entr call icle osu m Cingulum

ule ps a r a lc ul na r e t In al

limb

Caudate (tail)

Claustrum

Fo rn ix

E

Anterior

Visual radiation

Insular gyrus

sulcus

Frontal lobe

Lateral fissure

BA SA LG AN GL IA

Parietal/temporal neuroepithelium and subventricular zone

Glioepithelium

Parietal/temporal stratified transitional field Posterior striatal neuroepithelium and subventricular zone

118

PLATE 83A GW37 Horizontal CR 320 mm, Y301-62 Level 5: Section 631


119

PLATE 83B Germinal and transitional structures in italics Precentral sulcus

Lateral fissure

Visual radiation

Frontal lobe

rus r gy a l u le p su Ins a l ca

Lateral fissure

Claustrum

ern Ext

ve nt ric le


Induseum griseum

For ni x Cave of the septum


Callosal sling Callosal glioepithelium

al s te r le u La l nuc ta sep

Stria medullaris


IVENTRICULAR COMPLEX ER

ANTERIOR COMPLEX

C

L

E

AL

O

M

PL

EX

C

IC OM BA U LA PL SA R EX B LG EL T AN GL IA T


Cingulum

Induseum griseum? Interhemispheric fissure Layer I Cortical plate

R RIO STE EX PO MPL CO

RA

R

Strionuclear V glioepithelium EN TR


DORSAL COMPLEX

NT

Glioepithelium


Diencephalic (thalamic) glioepithelium/ependyma

um os l l ca

THALAMUS CE


of en m o ra r Fo Mon

Third ventricle Subfornical organ

Lateral ventricle


Habenular nuclei Stria medullaris

tricular nuclei

Choroid plexus

s pu r Co

Pulvinar

Dorsomedial nucleus

Periven

Fornix

SEPTUM

s ucleu al n r e t l la tra n Ce

Stria terminalis

Corpus call osu (splenium) m


Stria terminalis

Triangular septal nucleus

Cingulate gyrus

u la Ve a n n u n te r tr a cle io l us r

al

Caudate (head)

et ic

rp us cal lo s um

te r

b

R

Cingulum

La

r lim


s u e s l du le c ral en t ral alli u u V p s s n p bu la t e le u s ca r Glo l nuc na r te In

P

Co

e r io

Fimbria/ fornix

DORSAL S PU HIPPOCAM

b ior lim Poster

Putamen A nt


Caudate (tail)

Paracentral lobule

Callosal sling

White matter

Callosal glioepithelium Fornical glioepithelium


Glioepithelium

Anteromedial striatal neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone

Parietal/temporal stratified transitional field Parietal/temporal neuroepithelium and subventricular zone

120



121

PLATE 84B Germinal and transitional structures in italics Visual radiation

Lateral fissure

Frontal lobe

s yru g r ula Ins

Lateral fissure

C

tr u la u s

Choroid plexus

m

li m r o ri ste o P

sule cap l a tern

Cingulum

Cingulate gyrus Interhemispheric fissure

Lateral septal nuc.

Fornix


SEPTUM

Median preoptic nucleus Anterior commissure


nu cl eu s



R

PERIVENTRICULAR C OM PL (thalamic) EX

R ET

SUB




CENTRAL COMPLEX

VENTRAL COMPLEX

White matter Fornical glioepithelium

Corpus callosum


Alvear glioepithelium Glioepithelium

Rostral migratory stream (source area) Anterolateral striatal neuroepithelium and subventricular zone

Fimbria/fornix


POSTERIOR COMPLEX

T ICULAR B E L

US

LAM

THA


Subgranular zone Pulvinar

Lateral habenular nucleus Medial habenular nucleus Pineal gland Third ventricle (pineal recess)

Third ventricle

Third ventricle

BASAL GANGLIA


Subiculum


THALAMUS


Dentate gyrus

medial nucleus

Parafascicular nucleus

Diencephalic glioepithelium/ependyma


DORSAL HIPPOCAMPUS Ammon's horn

Caudate (tail) Stria terminalis


Forel's fields

Lateral ventricle

ral late nucleu al s Ventral

Zona incerta


B ed nu th e s c le u s o f Medial t e r t r ia septal nuc. minalis

et icu lar Ce nt r

na lc ap su le

e r io

r lim b C t era aud Co l rpu ven (hea ate tri (ro s call d) c str osu le um m )

La

u s t) lid e n l pa gm u s l se b lo a G tern x (e

Reu nuc niens leus

Ant

en m a t Pu

(in Glo te bu rn s al pa se lli gm du In ent s ter )

Ex

b



Parietal/temporal stratified transitional field

Parietal/temporal neuroepithelium and subventricular zone

122



123

PLATE 85B Germinal and transitional structures in italics Meyer's loop (visual radiation)

Lateral fissure

tam

(he

ad)

Cingulate gyrus


Diagonal band of Broca (vertical limb) Median preoptic nucleus


s

u cl e

r n u

la


Forel's fields


Parafascicular nucleus Massa

Third ventricle intermedia Third ventricle PERIVENTRICULAR CO MP LE X

Diencephalic (hypothalamic) glioepithelium/ependyma CENTRAL COMPLEX

NT

R


Cortical plate

White matter

M PLEX

POSTERIOR COMPLEX


Subgranular zone Callosal glioepithelium

T


CO

Glioepithelium


Layer I


L



E

BASAL GANGLIA

L

VENTRAL COMPLEX

B


A

Habenulo-interpeduncular tract Posterior commissure

THALAMUS

CE

RETICU L A R



Ventral ateral nu posteromedial al l nucleus tr


US LAM THA SUB


Zona incerta

Subiculum

Pulvinar

PR ET EC TU M

b

Fo rn ix

ate

lim

Anterior commissure

Ca ud

io r


SUPERIOR COLLICULUS

Cingulum

Corp us c (rostr allosum um)

ter

Dentate gyrus

Fimbria/fornix

us cle

An


R e t i c u

Lateral ventricle

u s t) ll id en a m s p seg u b l lo a G tern x (e

(in Glo te bu rn s al pa se lli gm du en s In t) ter na lc ap su le

Pu

Lateral ventricle

DORSAL HIPPOCAMPUS Ammon's horn

Po ste rio rl im b

le psu a c al ern Ext en

Ce n

Insular gyrus

Frontal lobe

Choroid plexus

strum Clau

Stria terminalis Caudate (tail)

Alvear glioepithelium Stem cells of choroid plexus

Posterior striatal neuroepithelium and subventricular zone Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

124



125

PLATE 86B Germinal and transitional structures in italics Lateral fissure

Stria terminalis

Median preoptic nucleus


HYPOTHALAMUS

PERIVENTRIC U LA

s

White matter

M EX PL

BE

VENTRAL COMPLEX

LT

Rostral migratory stream (source area) Lateral migratory stream (infiltrates the claustrum)

C la

u st

rum


THALAMUS POSTERIOR COMPLEX

BASAL GANGLIA


Cortical plate

TECTUM

CO

AR


Layer I

MIDBRAIN

L

ICUL

(infiltrated by the rostral migratory stream)



X LE

RA

RET

US LAM THA SUB

Accumbent neuroepithelium and subventricular zone

Subiculum

Cerebral aqueduct

RC OM P

NT

Diencephalic (hypothalamic) glioepithelium/ependyma


eu

r n u

ula

Mammillothalamic tract Fornix Parafascicular Central Subcommissural gray organ nucleus Paraventricular nucleus HabenuloThird Third ventricle ventricle interpeduncular tract

CE

PREOPTIC AREA


Pulvinar


Cen

Anterior commissure



Dorsomedial nucleus

Dentate gyrus



l la tra

Forel's fields

Ammon's horn

SUPERIOR COLLICULUS

terminalis



leu al nuc s ter Centromedian nucleus

rna l ca psu Ansa le ( lenticularis a nt erio Corp r lim us ca Nucl llosu b) m (ro eus a strum c cum ) bens Subcallosa Bed nucleus of l arreea the stria

Retic

Me

Inte

Zona incerta

DORSAL HIPPOCAMPUS

Fimbria/fornix

l ia te ed la M icu dy n ge bo

s d u t) lli m e n a p g us l se mina b lo a la G tern x (e

cl

n

du ll

me

ar y (in Glo te bu rn s al pa Ce se lli reb gm du ra en s lp t) ed un c le

ta Pu

us

Lateral ventricle


ule caps nal r e t Ex

C la


tr u m

In (poterna ste l ca rio psu r li le mb )

Insular gyrus

Frontal lobe

Choroid plexus

Caudate (tail)


Subgranular zone

Alvear glioepithelium Glioepithelium

Posterior striatal neuroepithelium and subventricular zone Temporal stratified transitional field Temporal neuroepithelium and subventricular zone

126



127

PLATE 87B Germinal and transitional structures in italics Caudate (tail)

Lateral fissure

en tam u P

(an teri or l im

b)

Diagonal band of Broca (vertical limb) Median preoptic nucleus


Red nucleus

An commterior issur e

Lateral hypothalamic area Lateral preoptic area

Subcallosal area


Zona incerta




Central gray

BT


LA MU



Tectum

THALAMUS

S

BASAL GANGLIA

VERMIS

MIDBRAIN

HA


POSTERIOR COMPLEX


Glioepithelium




Clau strum


Layer I

Cerebral aqueduct

Tegmentum

SU


White matter

Raphe nuclei

PREOPTIC Third AREA HYPOTHALAMUS ventricle


Subiculum

Cortical plate


Medial forebrain bundle and ansa lenticularis


Dentate gyrus

CEREBELLUM

Dorsomedial nucleus

Periventricular nucleus

Ammon's horn

Culmen IV, V



SUPERIOR COLLICULUS

Nucleus accumbens

e

Fo rn ix

s u le

SUB INN STAN OM TIA INA TA

cap

Ve stri ntral atu m

rna l

s lidu ) pal ment s u g b e Glo rnal s te (ex

DORSAL HIPPOCAMPUS

Fimbria/ fornix

l dia e Me culat i gen body

e sul cap l na ter Ex

I n te

a

Choroid plexus


m

Interna (posteriol capsule r limb)

Cl

ru u st

(in Glo te bu rn s al pa Cer se lli eb gm du ra lp en s e du Su t) n bth cl nu ala cle m us ic

Insular gyrus

Frontal lobe

Lateral ventricle

Stria terminalis


Temporal stratified transitional field Temporal neuroepithelium and subventricular zone

128



129

PLATE 88B Germinal and transitional structures in italics Temporal lobe s

Subcallosal area

lp Ce reb ra

Su bs ta

nt

Pa ra br

Supramammillary area


HYPOTHALAMUS

Red nucleus

ial ? ed us M nisc m le

COINFE LL RI IC OR UL US

Interpeduncular Raphe nuclear complex nucleus

tr ac

Tegmentum

Mesencephalic glioepithelium/ ependyma

t

Ce

b re

MIDBRAIN

Central gray Cerebral aqueduct

lp

ed

O pt ic

tr

cle

ac t In

uncinate fasciculus)

Ventral striatum

ter na

Optic tract

Central nucleus

Cortical plate

lc

ap

su



le (po BAS ste rio A L Exte rl GAN im rnal G b) LIA caps ule Glioepithelium Fornical glioepithelium Subgranular zone


Layer I

VERMIS

HEMISPHERE


Medial geniculate body (POSTERIOR COMPLEX)

White matter

Tectum

THALAMUS

Lateral migratory stream (infiltrates the

CEREBELLUM

Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

ra

un

Occipital gyrus

Anterior lobe HI-HV

Habenulo-interpeduncular tract Medial longitudinal fasciculus Oculomotor nuclear complex (III)

Oculomotor nerve (III)?


Dorsal nucleus of lateral lemniscus

Reticular formation

c. nu al hi

ic

endopiriform nucleus)

ra nig

pt


ia

ac

Ventral te gmental area

Third ventricle PREOPTIC AREA

le nc

O


ed u

S IN UBS NO TA M NT IN IA AT A

O pt ic tr ac t

tub cto

Dia go (ho nal b riz and ont of al l Br im oca b)

Ol fa


Lateral lemniscus

Occipital lobe

Declive VI

Ventromedial nuc.

Lamina terminalis

ct tra

ssure ary fi Prim


Fornix


Culmen IV, V

Supraoptic nucleus Periventricular nucleus

tic Op

Subiculum

Centralis III Lingula I, II

ypo ral h rea Latelamic a th a

Ammon's horn Dentate gyrus

Stria terminalis

Lateral tuberal nucleus

DORSAL HIPPOCAMPUS

le ric nt ve

Choroid plexus Fimbria/ fornix


ry

Islands of Calleja

al ter La

Central nucleus of amygdala?

erc le

Frontal lobe

g

ate cin lus Un cicu fas

En do nu pirif cle or us m

In

su

r la

u yr

Caudate (tail)

co Ant mm eri iss or ur e

Lateralfissure fissure Lateral

ule al caps Extern




130



131

PLATE 89B Internal capsule (posterior limb)

r

Amm m

lp

ed u

lu cu bi

Su bs ta

Su

CA 3)

A m mon's horn (

La

te

A com nter mi ior ssu re

Ce reb ra

n

n tia

nucle

Oculomotor nerve (III)? Superior cerebellar peduncle


MIDBRAIN


AMYGDALA

endopiriform nucleus)



VERMIS

Cerebral aqueduct

Central nucleus

Trochlear nerve (IV)?

HEMISPHERE

Tectum


Tegmentum Alvear glioepithelium



re

Red nucleus

complex

Folium VIIa

Raphe nuclear

HYPOTHALAMUS


Dorsal tegmental nucleus us


Reticular formation



cus

White matter

Declive VI

l chia

L ateral lemnis

a r y fi s s u

Medial mammillary nucleus Third ventricle Interpeduncular nucleus

bra Para

a igr

Simplex lobule HVI

Anterior lobe HI-HV

rim

O pt ic tr ac t

le nc

Culmen IV, V Centralis III


CEREBELLUM

Lingula I, II


a

OR S RI LU FE U IN L L IC CO

Lamina terminalis

Ventromedial nucleus Arcuate nucleus

nt



le lobu form Ansi Crus I IA HVI

a te r a l B a s o l le x com p ial med tico x Corcomple

De

alo l gd mpa y a Am poc ea hip ar


e gyr ntat De

Subiculum

ry cto ) lfa rm y o ifo ar pir im x ( P r o rte c

Stria terminalis

Frontal lobe

A

(C

Temporal lobe

P

Central nucleus


n

1)

us

al HIP on' ve sh POC nt o ric r AM le PUS te g y r us

Uncinate fasciculus



Caudate (tail)

Dorsal nucleus of lateral lemniscus

Subgranular zone VENTRAL HIPPOCAMPUS



AMYGDALA Lateral migratory stream (infiltrates the

DORSAL HIPPOCAMPUS

uncinate fasciculus)




132



133

PLATE 90B Germinal and transitional structures in italics Lateral ventricle

r

Optic chias m

pe



Den tate

mo (CAn's h 1) orn

Am

Su bic ulu m

us isc

Reticular formation L ate r al

Su


PONS

em n

l em

n

us isc

Cerebr al p

HEMISPHERE

Spinocephalic tract

Subiculum

ral ate sol lex Ba omp c

Central nucleus

Primary fissure

Subgranular zone



Stria terminalis Molecular layer Granular layer Hilus


Layer I

Dentate gyrus



Folium VIIa

ll

Fastigial nucleus

Pyramis VIII

ia

Declive VI rd ee p n u cle i

ed

lum

Centralis III

ve

Medial longitudinal fasciculus Dorsal longitudinal fasciculus

y gra ne nti o P

u n cle

i o r m Fo e d . . ur t h ve nt


Fastigial nucleus


AMYGDALA

through the uncinate fasciculus)

ed


Ventral tegmental nuc. Tectospinal tract

M

al cortex Entorhin


Mesencephalic nuc. (V) Locus coeruleus


C e re b r al

Arcuate nucleus Third ventricle (infundibular recess)

Ansiform lobule (Crus I HVIIA)


Parabrachial nuc. Dorsal tegmental nuc.

Pon tin e gray


Simplex lobule HVI Dentate nucleus

Pontine gray

Oculomotor nerve (III)?

Cortical plate

la

Subic ulum

cle un d pe

Anterior lobe HI-HV

White matter

CEREBELLUM

bel

a ter a l B a s o l p le x com


Superior cerebellar peduncle (at base of red nucleus)

Lateral migratory stream (percolates

Primary Primary fissure fissure


Uncus



C e re

Stria terminalis

gyr us

HIPPOCAMPUS

Uncinate fasciculus

HYPOTHALAMUS

Temporal lobe

VERMIS

134



135


CEREBELLUM Ansiform lobule (Crus I HVIIA)

Simplex lobule HVI Anterior lobe Middle and inferior HI-HV cerebellar peduncles

Primary fissure

Ventral nucleus of the lateral lemniscus?

Pontine gray

Motor nucleus (V)

PONS

Spinocephalic tract

Germinal trigone

Ve sti bu comlar n ple ucle ar x Mesencephalic nuc. (V) Locus coeruleus

Parabrachial nuc. Principal sensory nuc. (V) L at e r a l

lemnisc u s

peduncle cerebellar Superior r Vestibular nuclea complex

M cer iddl eb e a ell nd ar in pe fer du io nc r les

VERMIS External germinal layer

Interpositus nucleus Dentate nucleus

HEMISPHERE Primary fissure

A (C nsifo rus rm II lob HV ul IIA e )

Tuber VIIb

emniscus



Choroid plexus



Folium VIIa

Reticular formation M e di a l l

Reticular tegmental nucleus of pons


Fourth ventricle te Ven gm tr n u en al c . ta l

Cerebellar deep nuclei

Pyramis VIII


Dentate nucleus

Uvula IX

Dorsal longitudinal fasciculus Medial longitudinal fasciculus Spinotectal tract

Lateral vestibular nucleus?

Nodulus X


Principal sensory nucleus (V) Fibers of the trigeminal nerve (V)

Ve sti bu co lar mp nu lex clea r

Transpontine corticofugal tract


136



137


CEREBELLUM Simplex lobule HVI

Primary fissure

Anterior lobe HI-HV

le unc ped r r le a l bel erio unc Inf r ped cere e l d lla id Vn eb e erv M cer e?

Trapezoid body

Reticular formation

Medial lemniscus

Ventral nucleus of the lateral lemniscus? Lateral lemniscus M

id

dle

cere

bellar ped

e uncl

Principal sensory nucleus (V)

Infer ior ce

Pyramis VIII

Motor nucleus (V)


VERMIS


Germinal trigone

ular Vestib ar nucle lex comp

PONS

Ansiform lobule (Crus II HVIIA)

Uvula IX

Medial longitudinal fasc.

Nodulus X

Spinotectal tract

Fourth ventricle



Paraflocculus


VI nerve?

Genu (VII)

Reticular tegmental nucleus of the pons

Pontine gray

Choroid plexus

Abducens nucleus (VI)

Superior olivary complex


Cerebellar deep nucleus

ar nucle bular Vesti complex

act inal tr trigem Spinal Spinal nuc. (V)

Dorsal cochlear nucleus Lateral lemniscus Ventral nucleus of the lateral lemniscus? Spinocephalic tract?


rebell ar pe dunc le

Floccular peduncle

Super ior peduncerebellar cle?


Dentate nucleus

Primary fissure

HEMISPHERE


138


See the entire section in Plate 79 (top).

139

PLATE 93B Germinal and transitional structures in italics Ansiform lobule (Crus I HVIIA) Primary fissure

Simplex lobule HVI

CEREBELLUM

HEMISPHERE

Anterior lobe HI-HV


Flocculus

Ventral cochlear nucleus (intermingled with VIII nerve bundles) VII nerve

Choroid plexus

MEDULLA

Motor nucleus (VII)


VERMIS


Paraflocculus


Paramedian lobule HVIIB

lear n

ucleus


Anterior lobe HI-HV Simplex lobule HVI

Dentate nucleus Cerebellar deep nucleus

HEMISPHERE Ansiform lobule (Crus I HVIIA)


ellar ereb ior c ncle r e f In pedu

l coch

Primary fissure


s Superior olivary cleu al nu V) complex Spin tract ( and

Dorsa

V nerve root (premyelination gliosis)

Ve sti b c o u la r m n pl u e x c le ar

Prepositus nucleus Dorsal motor nucleus (X)

Uvula IX

Hypoglossal nucleus (XII)

Choroid plexus


PONS Lateral lemniscus

Fourth ventricle

Dorsal longitudinal fasciculus Medial longitudinal fasciculus Spinotectal tract

Paraflocculus


r n ce edu p Reticular formation

Medial lem and trapezoidniscus body

Pontine gray

Spinal nucleus and tract (V) uc. yn itar act Sol nd tr a

Spinocephalic tract

IX nerve root rior ar fe ll In ebe cle

te nea s Cu cleu nu


Transpontine corticofugal tract Pontocerebellar fibers


140



See the entire section in Plate 79 (bottom).


141


Section 1311

Section 1331 CEREBELLUM

CEREBELLUM



External germinal layer Simplex lobule HVI

HEMISPHERE Par am ed HV ian lo IIB bul Biv e ent ral H V lo b III u le

Flocculus Corticospinal tract (pyramid)

Inferior olive

Nuc. of Roller

Dorsal longitudinal fasciculus Fourth ventricle/central canal Area postrema


Pontine gray

Dorsal motor nuc. (X) Dorsal sensory nuc. (X)

Nucleus ambiguus


Infer

IX nerve root?

MED ULLA

ior peducerebella r ncle

Gracile nucleus Glioepithelium/ependyma


Simplex lobule HVI

Anterior lobe HI-HV

HEMISPHERE Middle cerebellar peduncle


PON S Middle cerebellar peduncle

m

Biv ent HEMISPHERE ral l HV obu III le

Choroid plexus

Spinocephalic tract Corticospinal tract (pyramid)


Flocculus

Spinocerebellar tracts

ra

Medial lemniscus Medial long. fas. and tectospinal tract

Gracile fasciculus


Flocculus

Py

l Cunea era te fa Lat cular sci leus cu reti uc. Spinal nuc (V) t Cu n and trac n nu ea S olit cle te Reticular a u Dorsal formation and trry nuc. s act accessory olive Hypoglossal (XII)

s lu

PO NS

Choroid plexus

A (C nsif ru or sI m I H lo VI bule IA )

Spinocephalic tract


id

S al Later nuc. a pinal nd nuc lar Cuneate fasciculus tra leu reticu ct ( s Cu Nuc. V) n n S e o u a ambiguus li cle te andtary n us Dorsal Gracile fasciculus u accessory olive Reticular tract c. Nuc. of Roller formation Central canal niscus Medial lem Raphe nuc. complex

Inferior olive

Medial long. fas. and tectospinal tr.

Grac nucle ile us

Hypoglossal (XII)

Dorsal motor nuc. (X) Dorsal sensory nuc. (X)

Commissural nucleus (X)

Glioepithelium/ependyma

MEDU LLA MED ULL A

X nerve root?


Flocculus Simplex lobule HVI

Paramedian lobule HVIIB External germinal layer Middle cerebellar peduncle

HEMISPHERE


142



See the entire section in Plate 80 (middle).


143


Section 1381

CEREBELLUM

Section 1441

Paramedian lobule

HEMISPHERE

M EDUL L A

Biventral lobule


M E DU L L A

C

us

Cuneate fasciculus Central canal Glioepithelium/ependyma

Cu

lu s ic u

a ef at ne

eb ell a r tracts

Choroid plexus

Flocculus

Paramedian lobule

HEMISPHERE Ansiform lobule (Crus I HVIIA)


Pyramidal decussation

Medial accessory olive Corticospinal tract

us

Spinal ) tract (V

sc

Spinal nucleus (V)

Cu nu nea cle te us

Spinal tract (V)

Central canal

ram Py

id

ior r e f In olive

ret Lat ic e u lar ral nu c.

Spinocer

s

L reticuateral lar n uc.

u cleu

cleus le nu aci Gr ul G racile fas c i c

Reticular formation

Dorsal accessory olive

Inferior olive

Raphe nuc.

Hypoglossal nuc. (XII)

olive

te n

y ssor cce la a i d

ea

id

Medial lemniscus (decussation)

neate fascicul Cu

un

Dorsal motor nuc. (X)

Nuc. ambiguus

ram e M

Central autonomic area

uc. yn itar act Sol nd tr a

Py Corticospinal tract

Lateral corticospinal tract

External cuneate nucleus

S pinocerebellar tract s

Gracile fasciculus Gracile nucleus Glioepithelium/ependyma

Reticular formation

Cuneate nucleus Spinal nucleus (V)

Biventral lobule HEMISPHERE Paramedian lobule

CEREBELLUM


144

PART PARTV: V:


This specimen is case number BX-15-60 (Perinatal RPSL) in the Yakovlev Collection. A female infant survived for one hour after a premature birth. Death occurred because a hyaline membrane obstructed the airway to the lungs. The brain was cut in the sagittal plane in 35-µm thick sections and is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). Since there is no photograph of this brain before it was embedded and cut, the photograph of the medial view of another GW32 brain that Larroche published in 1966 (Figure 6) is used. Photographs of 6 different Nissl-stained sections (Levels 1-6) are shown at low magnification in Plates 96-101. The core of the brain and the cerebellum are shown at high magnification in companion Plates 102AB-107AB for Levels 1-6. Very high magnification views of different regions of the cerebellar cortex are shown in Plates 108-111. Because the section numbers decrease from Level 1 (most medial) to Level 6 (most lateral), they are from the left side of the brain; the right side has higher section numbers proceeding medial to lateral. The cutting plane of this brain is nearly parallel to the midline in anterior and posterior parts of each section. However, the occipital lobe has been displaced toward the left. For example, the occipital lobe in Level 1 (Plate 96) is from the right side of the brain. There is no occipital lobe in Level 2 (Plate 97), and the left occipital lobe first appears in Level 3 (Plate 98). The sections

chosen for illustration are spaced closer together near the midline to show small structures in the diencephalon, midbrain, pons, and medulla. Y15-60 contains the same group of immature structures that are in the GW37 brains, except all of these structures are slightly more prominent. In the cortical regions of the telencephalon, remnants of the germinal matrices are present in all lobes of the cerebral cortex where the neuroepithelium/subventricular zone are presumably generating neocortical interneurons. Migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields, thin in the occipital lobe, and thicker in the frontal, parietal and temporal lobes. More neurons, glia, and their mitotic precursor cells are migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Within the lateral parts of the cerebral cortex, the lateral migratory stream contains neurons and glia that percolate through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus. These cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a thick neuroepithelium/subventricular zone overlying the striatum and

nucleus accumbens where neurons and glia are being generated; some of these, especially from the accumbal area, will enter the rostral migratory stream. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Just as in the GW37 specimens, the septum, fornix, and Ammon’s horn have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle. Most of the structures in the diencephalon appear to be settled and are maturing, and the third ventricle is lined by a thin glioepithelium/ ependyma. In the midbrain and anterior pons, there is a slightly thicker and more convoluted glioepithelium/ependyma lining the posterior cerebral aqueduct and anterior fourth ventricle. A thin glioepithelium/ependyma lines the fourth ventricle in the posterior pons and anterior medulla, but that thickens in the posterior medulla. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is actively producing basket, stellate, and granule cells. The germinal trigone is visible at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia are originating here.

145

c e sul gulat n i C

Central sulcus

us

gi n M ar

u al s

lc u

s

yru Cingulate g s

Precuneus

Corpus callosum le n

Genu

m

DIENCEPHALON Hypothalamus

T E MP

LL

OBE

us

Cuneus

Calcar ine s

Lingula

ulc

us

Cerebellar vermis

O

RA

iet

m ctu Te IN BRA MID tum men Teg

Gyrus rectus

r Pa

l ita p i c oc o-

lc su

PITAL LOB CI E OC

iu

tum

Thalamus

lenial area sp

Re tro

Sp

Fornix

Subcallosal area

PA RI E BE LO

Su pe rio r

rus gy l ta

Postcentral gyrus

L TA

on fr

Precentral gyrus

Sep

TAL LOB FRON E

PARACENTRAL LOBUL E

PONS

DUL ME LA

Cerebellar hemisphere

Spinal cord Figure 6. Midline sagittal view of a GW32 brain with major structures in the cerebral hemispheres and brainstem labeled. (This is part of Figure 2-9 on page 27 in B. A. Curtis, S. Jacobson, and E. M. Marcus (1972) An Introduction to the Neurosciences, Philadelphia: W. B. Saunders. The photograph was originally published by J. C. Larroche (1966) The development of the central nervous system during intrauterine life. In: Human Development, F. Falkner (ed.), Philadelphia: W. B. Saunders, page 259.)

146



5 6 7 8

Diencephalic (hypothalamic) glioepithelium/ependyma Diencephalic/mesencephalic glioepithelium/ependyma Mesencephalic glioepithelium/ependyma Pontine glioepithelium/ependyma

Medullary glioepithelium/ependyma Germinal trigone (cerebellum) External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 102A and B. Central sulcus Precentral gyrus


Postcentral sulcus


Paracentral lobule

White matter Superior frontal gyrus Superior rostral gyrus?

Frontal lobe

Gyrus rectus

Corpus callosum


Cave of the septum

Choroid plexus

Fornix

Genu

Septum

2

Anterior commissure Third ventricle

Subcallosal area

1

H

1

Splenium

Pineal gland Posterior commissure

Midbrain Tegmentum

Pontine gray

Fourth ventricle

3

4

6 Cerebellum

Pons

la ul



(vermis)

7

ed

Pyramid (corticospinal tract)

Calcarine fissure

M

High magnification views of the cerebellar cortex are in Plates 108-111.


re fissu

Occipital lobe


eric

sph emi

erh

*Int

Tectum

s mu ala h t o yp

Optic chiasm Mammillary body Cerebral peduncle

Parietal lobe

a? gul Lin

8

Precuneus

8

s neu Cu

Inferior rostral gyrus?

Postcentral gyrus

Gracile nucleus Gracile fasciculus

* The occipital lobe in this section is from the opposite side of the midline.

147

PLATE 97 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5

Rostral migratory stream Accumbent neuroepithelium and subventricular zone (intermingled with the source of the rostral migratory stream) Callosal sling Callosal glioepithelium Fornical glioepithelium

6 7 8 9 10 11


Septal glioepithelium/ependyma Strionuclear glioepithelium Pontine glioepithelium/ependyma Germinal trigone (cerebellum) External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 103A and B. Superior frontal gyrus

Cingulate sulcus

Precentral gyrus


Frontal lobe

Paracentral lobule

Cave of the septum

11 Frontal lobe

Cingulate g yru

Corpus callosu

Cingulate gyrus Sub

Orbital gyri

3

cal

Genu los

al a

rea

5

6

7

Sept um

2

Cortical plate White matter Layer I

1

Gyrus rectus

11

Fornix

Hypothalamus

Pontine gray Transpontine corticofugal tract

Splenium

MidbrainTectum Tegmentum



Fourth ventricle

Pons

8

la ul ed M

Pyramid (corticospinal tract) Inferior olive

Parietal lobe

Thalamus

Anterior Habenula commissure Nucleus accumbens Olfactory tubercle

Olfactory bulb Optic nerve (II) and chiasm Cerebral peduncle


Precuneus

4

m

Lateral ventricle

Fornix

s

Cerebellum (vermis)

9

10 Cerebellar deep nuclei

Cerebellum (hemisphere) Cuneate nucleus

148



6 7 8 9 10

Rostral migratory stream Accumbent neuroepithelium and subventricular zone (intermingled with the source of the rostral migratory stream) Rostral migratory stream (source area) Frontal neuroepithelium, subventricular zone, and stratified transitional field Callosal glioepithelium

Fornical glioepithelium Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)


Central sulcus

Precentral gyrus

Postcentral gyrus

Cingulate sulcus



10 Frontal lobe

C in g

u lu m

5

Layer I

Orbital gyri

late g C ingu yr us Corpus callosum

Lateral ventricle

4

3

Basal ganglia

2

5

Parietal lobe

6

s neu Cu

Subthalamus Tectum

Midbrain Tegmentum

Ventral hippocampus

Occipital lobe

Lateral lemniscus

Primary visual cortex Cingulate gyrus (retrosplenial area)

Cerebral peduncle Middle cerebellar peduncle

Pons


Medulla


rm

9

reb e llu m

em

H

Inferior olive

Ce

Ve

is

Pontine gray



Splenium

Anterior commissure

Optic tract

s eu un c e Pr


Thalamus Internal capsule

Hypothalamus

1

Fornix

8

7


Paracentral lobule

10

i s p h e re

9


149


Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium, subventricular zone, and 8 Amygdaloid glioepithelium/ependyma 1 stratified transitional field 2 3 4 5 6 7

Paracentral neuroepithelium, subventricular zone, and stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Callosal glioepithelium

9

Anterolateral striatal neuroepithelium and subventricular zone (intermingled with the source of the rostral migratory stream)

10


11



12



13

Subpial granular layer (cortical)


See detail of brain core and cerebellum in Plates 105A and B. Precentral gyrus Central sulcus Postcentral gyrus

Precentral sulcus

White matter

Postcentral sulcus Superior parietal lobule


2

s yru al g ont r f e ddl Mi

1

Frontal lobe

1

10

Basal ganglia

9

Corpus callosum

5 Thalamus

Internal capsule

Choroid plexus

Fornix

Occipital lobe

Cuneus

Ventral hippocampus

7 6

Primary olfactory cortex (piriform) Amygdala


Dorsal hippocampus

8

13

Parietal lobe Parietooccipital sulcus

Subthalamus

Anterior commissure

Orbital gyri

Angular gyrus?

4

11

Lateral ventricle

9

Paracentral lobule

3

Lingula?


13

Cerebellum (Hemisphere)

Calcarine fissure

12

Entorhinal cortex Damaged areas in section


12

Cerebellar deep nuclei Middle and inferior cerebellar peduncles

150

PLATE 100


4 5 6

Central sulcus Precentral gyrus

Postcentral gyrus


Angular gyrus

Layer I

13 M id

dl

Supramarginal gyrus

s gyru n ta l o r f e

Frontal lobe

Paracentral lobule

Coro na

2 10

r a di a ta

1

Basal ganglia

Claustrum

In s

External capsule

ula rg Orbital gyrus

8


8 9 Uncus

Th

Lateral ventricle

s

13

yru


Endopiriform nucleus Anterior commissure

6

ala

mu

Parietal lobe

11 5

Internal capsule

la

3

yg da

1 2

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal stratified transitional field 7 Subgranular zone (dentate) Parietal neuroepithelium, subventricular zone, and 8 Lateral migratory stream (cortical) stratified transitional field 9 Amygdaloid glioepithelium/ependyma Occipital neuroepithelium, subventricular zone, and stratified transitional field 10 Posterior striatal neuroepithelium and subventricular zone Parahippocampal neuroepithelium, subventricular zone, 11 Strionuclear glioepithelium and stratified transitional field Fornical glioepithelium 12 External germinal layer (cerebellum) Alvear glioepithelium 13 Subpial granular layer (cortical)

Am


Lateral ventricle

s

ve Lat nt er ric al le

us mp ca o us pp yr Hi lg a p am oc pp i h ra Pa

Occipital lobe

Lingula?

7

3

4 Cerebellum (Hemisphere)



Choroid plexus

12

151


Alvear glioepithelium Lateral migratory stream (cortical)

Amygdaloid glioepithelium/ependyma

7


8


9


10




Precentral gyrus

Postcentral sulcus Angular gyrus

Precentral sulcus White matter Cortical plate Layer I

Frontal lobe

10


Claustrum

Insular gyrus

Orbital gyrus

l sa a Ba ngli a g

Anterior commissure

10

Primary olfactory cortex (piriform) Endopiriform nucleus Uncus


Internal capsule

External capsule

Lateral fissure

Parietal lobe 1

Paracentral lobule

s yru al g t n o e fr ddl Mi

6 a

3 4 5

6

yg da l

2

Parietal neuroepithelium, subventricular zone, and stratified transitional field Occipital neuroepithelium, subventricular zone, and stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field

Am

1


5

3

al te r c le L a n tr i ve

us gyr pal cam o p p ahi Par

8

7

s pu m ca o p ip H

Choroid plexus

4

Lateral ventricle

2

l ra po e m b Te lo


Supramarginal gyrus

Occipital lobe Fusiform gyrus?


9

152



153

PLATE 102B Posterior commissure


PREO PTIC AREA A REA


2

Optic chiasm Third ventricle (infundibular recess) Arcuate nucleus

Mammillary body


Substantia nigra

sciculus i na l fa

E

C

Uvula IX

D

POSTERIOR LOBE

D

CE

Corticospinal tract

Hypoglossal nucleus (XII) Medial longitudinal fasciculus and tectospinal tract Lateral corticospinal tract (medial edge)

Germinal trigone (cerebellum) External germinal layer (cerebellum) Damaged areas in section

Gracile nucleus Dorsal motor nucleus (X)


SPINAL CORD

Medial motor nucleus (spinal cord)

Declive VI

Folium VIIa

8

Tuber VIIb

Pyramis VIII

Gracile fasciculus Pyramidal decussation

N

R T C

LUM

itud

E

INFERIOR LOBE

Choroid plexus

Reticular formation

B

B

V E R MI S

Nodulus X

EL

Fastigial nucleus

EB

5

ER

ng l lo

s

Pyramid

Cerebellar glioepithelium/ependyma

Raphe migration

Culmen IV, V

Lingula I, II

7

rsa

c ulu


8

MEDULLA

Preoptic glioepithelium/ependyma Hypothalamic glioepithelium/ependyma Mesencephalic glioepithelium/ependyma

Do

iscus l lemn Media


Fourth ventricle

6

9

A

III

Reticular formation


BE LO R RIO TE N A Centralis

4

ci al fa s

Trapezoid body?

A

C

l longitudin


Superior medullary velum

Inferior colliculus

Cerebral aque duc t

M e dia

Raphe nuclear complex Medial lemniscus

PONS


Central gray


Reticular formation


Trochlear nerve root?



Pontine gray

1 2 3 4 5 6 7 8 9

3


Middle cerebellar peduncle Transpontine corticofugal tract (thick longitudinal bundles)

3


TEGMENTUM


TECTUM

MID BR AIN M ID BRA IN

Substantia nigra

Oculomotor nerve (III) Cerebral peduncle

Pontocerebellar fibers (thin transverse bundles

Central gray

3


Superior colliculus

BE

HYPOTHALAMUS


Pretectum

Ce aqu rebra ed u l ct

LO

Premammillary area

Pineal gland


L

Lamina terminalis

1

Third ventricle

A

Preoptic periventricular nucleus



B


C


D


E


154



155

PLATE 103B Lateral ventricle

Fornix

3

2

4

Str


Ante comm rior issure

Bed nucleus of the stria terminalis (posterior divisio division n))

Forel's fields

Medial fo r

Centromedian nucleus eb


r

?

Substantia nigra


MID BR A IN

Red nucleus

Superior colliculus

Central gray

TEGMENTUM TECTUM

Cerebral peduncle Transpontine corticofugal tract (thick longitudinal bundles)

Reticular formation

Parabrachial nucleus?

Inferior colliculus


Cuneate fasciculus

BE L

LO

Pyramis VIII

EM

9 Folium VIIa

A C

Biventral lobule (HVIII)

Declive VI

UM

Cuneate nucleus

H

C

D

Paraflocculus (tonsil, HIX)

LL

Reticular formation

Int er nu posit cle us us

Uvula IX

E

Corticospinal tract

MEDULLA

B

n u stig ia c le l us

Nodulus X

E

B


Nucleus Solitary ambiguus nuclear complex

9

E

V E R MI S B Fa

8

E

OR LOB

ANTERI

e cl un ed rp lla be re

10


6

Choroid plexus

ce



s

9

or

Germinal trigone (cerebellum)

id

8

ri

7


Medial accessory olive

7

Reticular formation Inferior olive (principal nucleus)

Fourth ventricle

u cle


5

Superior olivary complex

A

Parabra c

pe

6

Reticular formation

R

Culmen IV, V

Centralis III

Lingula I, II

nu


Locus coeruleus

A

Su

5

Arcuate nucleus (medulla,with cells from the raphe migration?)


CE

Lateral lemniscus

al hi


Trapezoid body?

Media l lem niscu s

4

PONS

P yram


Pontine gray

Reticular formation

llar ebe cer e ior ncl per du Su pe



3




2


Pretectum

ndle


bu

Optic chiasm and tract



n

HYPOTHALAMUS


1

10

Habenular nuclei


ai

Lateral preoptic area Lateral hypothalamic area Supraoptic nucleus

Induseum griseum

Dorsomedial nucleus

X

Subcallosal area


CO M PL EX

is

Bed nucleus of the stria terminalis (anterior division)

ANTERIOR COMPLEX

ed

LE

Olfactory tubercle

ra


MP CO AL e u s TR l nucl C E N l l a t e ra

Nucleus accumbens


C e nt

1


Fo rn ix

ar

THALAMUS

m

2 ll

DO RS AL

ia

u

Lateral septal nucleus

Stria terminalis

T EN

R

Tuber VIIb

C Paramedian lobule (HVIIb)

ISPHERE



B


C


D


E


156



157

PLATE 104B Lateral ventricle

Stria terminalis


M ID BR A IN

Su

bs

Pontine and medullary glioepithelium/ependyma

9 10


Primary visual cortex (in occipital lobe)

Lateral lemniscus


Superior cerebellar peduncle Damaged areas in section Centralis III

Pontocerebellar fibers (thin transverse bundles) Pontine gray Middle cerebellar peduncle

P ON S

Motor nucleus (VII)?

) (V us cle u n y tor sor Mo sen pal s (V) i c u n Pri nucle

Inferior olive (principal nucleus)

Lingula I, II

Spinal nucleus (V)

9

Primary fissure

C

E OR LOB

ANTERI

V E R MI S


le nc Superior

vestibular nucleus

8

Dentate nucleus

Floccular peduncle

Fourth ventricle (lateral recess

MEDULLA


Culmen IV, V

Crus I ansiform lobule (HVIIA)

E R E

8

Nucleus of the lateral lemniscus (dorsal)

a

e to

H


gr

C pl hor ex oi us d

7

ni

c er ebe lla rp ed u


ia

Inferi or

6


nt

ri Pa

ta

s


H E M I S P Crus II ansiform lobule (HVIIA)


Paramedian lobule (HVIIb)

M



ip i

lc u

LU

4 5

ta

c -o c

u ls

EL


TECTUM

B

3


E

2


Fasciola cinereum

Superior colliculus

R


Pulvinar

E

1

Reticular formation


Inferior colliculus

Entorhinal cortex


lum gu Cin

10

POSTERIOR COMPLEX

Pretectum

TEGMENTUM

1

) dy (bo

X

act


Subthalamic nucleus

ncle edu al p ebr C er

ic tr O pt

ix rn Fo

s

nominata

LE

ti a in

ial romed l poste Ventra nucleus

MP

sta n


THALAMUS

u cle nu ral

ub

S

Olfactory sulcus

Forel's fields

Globus pallidus

5

CO

Nucleus accumbens

Orbital gyrus

l a te

BASAL GANGLIA Olfactory tubercle

r al

leu uc

s

Internal capsule

VENTRAL COMPLEX

AL

T

A comnterior mis sure

2


TR

Internal capsule

VENTRAL COMPLEX

C e nt

3

Ventral lateral nucleus CEN


C ral n SADLorsolate

n ar ul tic Re L E CUL A R B

he ft s o lis leumina c u r d n te Be stria

RETI

7

6


X PLE OM ucleus

R DO

um los cal us rp Co

4

4

Choroid plexus

9

158



159

PLATE 105B Frontal neuroepithelium, subventricular zone, and stratified transitional field

Lateral ventricle Anterolateral striatal neuroepithelium and subventricular zone

le

o

b) im rl o i r ste

ap Intern al c

e ul ps b) a l c lim na r e r e r io t In a n t External segment (

Globus pallidus

BASAL GANGLIA

Zona incerta




POSTERIOR COMPLEX

Corpus callosum (splenium) DORSAL HIPPOCAMPUS

Pulvinar

Sub th n u c a la m leu ic s




Optic tract Primary visual cortex (in occipital lobe)

SUBSTANTIA INNOMINATA Amygdalohippocampal area


ve n

al

VENTRAL HIPPOCAMPUS

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Subpial granular layer

Dentate gyrus m culu Subi

Primary fissure

Ammon's horn

te r

La

Basolateral complex


Subgranular zone

Central nucleus

AMYGDALA Lateral olfactory tract

Cer Substantia nigra ebr Optic trac MIDBRAIN al p t edu TEGMENTUM ncl e

cle




tr i

Lateral migratory stream?

Choroid plexus

THALAMUS

s

Anterior commissure

Co rt co ico m me pl d ex ia l

Ventral striatum

Orbital gyrus

LT

Internal segment

Putamen Ex ca ter ps na ul l e

BE

le su ap lc na ter In



u cle nu ar ul tic AR Re C U L I RET



VENTRAL COMPLEX


su

(p

Stria termnalis

nix For




Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium

En

to

in rh

c al

or

tex



E OB

A

L OR V) I E R I-H N T (H


Dentate nucleus Flocculus (HX)?


Flocculus (HX)?

Biventral lobule fragments?

CEREBELLUM (HEMISPHERE)






160



161

PLATE 106B Germinal and transitional structures in italics Parietal stratified transitional field


Corona radiata

Lateral ventricle

rl

Strionuclear glioepithelium b) im

Ex S

(percolates through the claustrum and endopiriform nucleus)

Pr

im

ar

BS

facto y ol

p

(

ir

i fo


rm)

Subpial granular layer Lateral migratory stream

a Ans ATA

An com terior miss ure IN M TA NT NO IA IN Intercalated Central masses nucleus

ry cortex


U

ent egm al s n r Inte aris icul

ic le

Orbital gyrus

Globus pallidus

ral v e n tr

le

s e ru sur gy fis al ter La

su

la r


Bas AM Y o com latera GDA LA ple l x

su

p ca al m rn ru t us

la In

Ventral striatum Endopiriform nucleus

(extends to the amygdala)

t men l seg a n r e Ext

L a te

te

C

lent

Optic tract

ia is S tr in a l m r te

id ro s ho exu C pl CA3

m Fi

br

Stria t er

Fimbria/ fornix

Occipital neuroepithelium and subventricular zone (thin)

CA3

THALAMUS

CA1

POSTERIOR COMPLEX

ia


Pulvinar

Stratum lacunosum moleculare Stratum radiatum


D

g te ta n e

Pyramidal layer

us yr

Am

m

' on

CA1 sh

Stratum oriens Alveus

Occipital lobe


n or

Lingula?

s HIPPOCAMPUS Subgranular zone gyru l pa CA1 am c o Dentate molecular layer ipp h ra Dentate hilus Pa ortex Dentate granular layer

Uncus

En


s

c

l eu

Pul vin ar

R e t i c ul ar

BASAL GANGLIA

nu

Internal c apsu le (

po

ste

m i n a l is

ri o

Putamen

Putamen

Parietal neuroepithelium and subventricular zone (thick)


to

in rh

al

c

Primary fissure




T AN

ER

IO

R


LO

BE

(

-H HI

V) Simplex lobule (HVI)





Medullary layer Granule cell layer Purkinje cell layer Molecular layer External germinal layer

162

PLATE 107A GW32 Sagittal, CR 270 mm, Y15-60 Level 6: Section 421


163


Precentral sulcus

Paracentral lobule

Frontal lobe

Parietal lobe



Parietal neuroepithelium and subventricular zone (thick) Posterior striatal neuroepithelium and subventricular zone Insular gyrus

lar Insu

us gyr

Stria terminalis


Putamen

te ra

s yru rg ula Ins e ur

La

is s lf

Extern

BASAL GANGLIA Strionuclear glioepithelium Ventral striatum


Uncus

DA LA

Central nucleus

e at ud Ca

Fimbrial glioepithelium

Fi

Lateral geniculate body Optic tract

Am

m

o

m

s n'

br

ho

ia

Parietal lobe

rn

HIPPOCAMPUS



(extends to the amygdala)



CA1

il) ta s( u e cl nu

Fusiform gyrus?

le ric nt e v al ter a L

Stria terminalis

CA1

am oc p ip ah r Pa

us yr g l pa

Occipital lobe


Temporal lobe External germinal layer

U


Fimbria/ fornix

nc

ina


YG

te fas ciculus


AM

(percolates through the endopiriform nucleus)

Ba co sola mp ter lex al

Orbital gyrus

A c o m n te r io m is r su r e

Intercalated masses



te

ul

al

ca

ps

(percolates through the claustrum)


tr

e


us

rn al ca ps ul e

C

la

um

In

L

ure fiss l a ater

Lateral ventricle Occipital neuroepithelium and subventricular Choroid zone (thin) plexus Strionuclear glioepithelium



le lobu plex ) Sim (HVI




164

PLATE 108 GW32 Sagittal CR 270 mm Y15-60 Level 1: Section 801 CEREBELLUM

External germinal layer (proliferative zone)

Anterior lobe (Culmen)

External germinal layer (premigratory zone)

Molecular layer

Granule cells (migrating)

Purkinje cell layer: (immature Purkinje cells without apical caps migrating and settling)

Purkinje cells (settled)

Granule cell layer Purkinje cell (migrating?)

Anterior lobe (Lingula) External germinal layer (proliferative zone) External germinal layer (premigratory zone)


Apical dendritic caps Molecular layer

See the entire Section in Plate 96. A mediummagnification view of the cerebellum is in Plates 102A and B.

Purkinje cell layer: (Maturing Purkinje cells with prominent apical dendritic caps settled in a monolayer)

Granule cell layer

165

PLATE 109 Central lobe (Folium) External germinal layer (proliferative zone) External germinal layer (premigratory zone)

Granule cells (migrating) Settling small Purkinje cells

GW32 Sagittal CR 270 mm Y15-60 Level 1: Section 801 CEREBELLUM

Molecular layer Purkinje cell layer: (scattered immature Purkinje cells migrating and settling)

Migrating small Purkinje cells Granule cell layer

Folium/Tuber

External germinal layer Molecular layer Granule cell layer

Medullary layer

See the entire Section in Plate 96. Central lobe cleft (The medullary layer reaches all the way to the external germinal layer)

A mediummagnification view of the cerebellum is in Plates 102A and B.

166

PLATE 110 GW32 Sagittal CR 270 mm Y15-60 Level 1: Section 801 CEREBELLUM

Posterior lobe (Uvula)

External germinal layer (proliferative zone) External germinal layer (premigratory zone) Molecular layer

Settled large Purkinje cells

Purkinje cell layer: (settled large Purkinje cells, widely scattered)

Granule cell layer

Migrating small Purkinje cells?

Inferior lobe (Nodulus)

External germinal layer (proliferative zone) External germinal layer (premigratory zone) Granule cells (migrating) Molecular layer

See the entire Section in Plate 96. A mediummagnification view of the cerebellum is in Plates 102A and B.

Purkinje cell layer: (Purkinje cells with basal cytoplasmic accumulations settled in a monolayer)

Basal cytoplasmic accumulations Granule cell layer

167

PLATE 111 3 Germinal trigone (at base of the Nodulus)

Germinal source of the external germinal layer earlier in development

GW32 Sagittal CR 270 mm, Y15-60 Level 1: Section 801 CEREBELLUM

2 Germinal source of the choroid plexus

1 Remnant of the cerebellar neuroepithelium

See the entire Section in Plate 96. Dense cell clusters that may be migrating cohorts of glia and Purkinje cells

A mediummagnification view of the cerebellum is in Plates 102A and B.

168

PART PARTVI: VI:


gy ru s

Postc ent ra l

us

gy ru ulc s ls

nt ra

Prec ent ra Ce l

rio rf r Su pe

Insular gyrus

p Su

PO

M

The approximate cutting plane of this brain is indicated in Figure 8 (facing page) with lines superimposed on the GW30 brain from the Larroche (1967) series. The anterior part of each section is ventral to the posterior part. As in all other specimens, the sections chosen for illustration are more closely spaced to show small structures in the diencephalon, midbrain, pons, and medulla. Illustrated sections are spaced farther apart when they contain only large brain structures, such as the cerebral cortex, basal ganglia, and cerebellum. Photographs of 24 different Nisslstained sections (Levels 1-24) are shown at low magnification in Plates 112-131. The core of the brain and the cerebellum are shown at high magnification in companion Plates 132AB-150AB for Levels 3-24.

Orbital gyri

TE

This specimen is case number W-187-65 (Perinatal RPSL) in the Yakovlev Collection. A male infant survived 17 hours after a premature birth. Death occurred because of a pulmonary hyaline membrane. Autopsy notes include a subarachnoid hemorrhage over the cerebrum, but the brain appears normal and is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). It was cut in the horizontal plane in 35-µm thick sections. Since there is no available photograph of this brain before it was embedded and cut, we use the lateral view of another GW30 brain that Larroche published in 1967 (Figure 7).

te La

ure fiss l ra

or mp e t or e ri

al

r gy

te m M id d l e

I n f e rio r t

RAL

us

por

e mp

LOBE

ITAL L O CIP BE OC

tal gyrus fron r o i fer n I

Angular gyrus al occipital gyri t er La

NTAL LOB FRO E

i

ma pra u S

BE LO

M

dd

rio lob r pa ule rie tal

inal gyru rg s

s y ru g tal s on yru g al nt o fr le

PARACENTRAL LOBULE PAR IE TA Su pe L

yr al g

us

l gy o ra

rus

Cerebellar hemisphere Medulla Spinal cord

Figure 7. Lateral view of a GW30 brain with major structures in the cerebral hemispheres labeled. (From the photographic series of: J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

169

GW30 HORIZONTAL SECTION PLANES

261 400 441 521 621 671 701 721

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

761 801 841 861 881 941 1001 1041 1081 1121 1161 1201 1241 1281 1351 1391

SECTION NUMBER

LEVEL NUMBER Figure 8. Lateral view of the same GW30 brain shown in Figure 7 with the approximate locations and cutting angle of the sections of Y187-65. (From the photographic series of: J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248).

Y187-65 contains more prominent immature structures than in the older specimens. A densely staining neuroepithelium/subventricular zone is present and presumably generating neocortical interneurons in all lobes of the cerebral cortex. The same thickness variations between the occipital and other lobes of the cerebral cortex are still there. Remnants of migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields. Many neurons, glia, and their mitotic precursor cells are still migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. The lateral migratory stream percolates through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus with dense streams of cells that appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a large neuroepithelium/subventricular zone overlying the striatum and nucleus accumbens where neurons are presumably generated; at least three subdivisions (anteromedial, anterolateral, and posterior) can be distinguished in the striatal part. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Other structures in the telencephalon, such as the septum, fornix, and Ammon’s horn, have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle. Most of the structures in the diencephalon appear to be settled and are maturing, but the third ventricle is lined by a more densely staining glioepithelium/ependyma than in the GW37 specimens. A convoluted glioepithelium/ependyma lines the cerebral aqueduct in the midbrain that continues into the anterior fourth ventricle. A smooth glioepithelium/ependyma lines the fourth ventricle through the posterior pons. A slightly convoluted glioepithelium/ependyma lines the floor of the fourth ventricle through much of the medulla. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is actively producing basket, stellate, and granule cells. The cerebellar cortex itself shows less definition between hemispheric lobules. The germinal trigone is at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia may still be originating here.

170

PLATE 112 Remnants of the germinal matrix, migratory streams, and transitional fields 1 Frontal subventricular zone 5 Parietal stratified transitional field 2 Frontal stratified transitional field 6 Cingulate stratified transitional field 3 Paracentral stratified transitional field 4 Parietal neuroepithelium and subventricular zone 7 Subpial granular layer (cortical)

Postcentral gyrus Postcental sulcus

Central sulcus Precentral gyrus Precentral sulcus



nt r a l l

ta rie Pa

Frontal lobe

ce

ule

Pa

ra


ob


e ob ll

Superior frontal gyrus Cingulate gyrus

Precuneus

Interhemispheric fissure Layer I Cortical plate

6

White matter

7

1 2

3 7

7 4

5

171

PLATE 113 1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 7 Parietal stratified transitional field Frontal stratified transitional field 8 Posterior striatal neuroepithelium and subventricular zone Callosal glioepithelium 9 Anterolateral striatal neuroepithelium and subventricular zone 10 Anteromedial striatal neuroepithelium and subventricular zone Callosal sling 11 Strionuclear glioepithelium Fornical glioepithelium Parietal neuroepithelium and subventricular zone 12 Subpial granular layer (cortical)


Central sulcus Postcentral gyrus Supramarginal gyrus

Precentral gyrus Middle frontal gyrus

Angular gyrus

ob ll ta rie Pa

Paracentral lobule Frontal lobe


C

or

La

e

Internal capsule

Basal ganglia

te r

Choroid plexus

a

l ve n tr i c l e pu s c a Cingulate llosum gyrus


Induseum griseum

Cingulate gyrus

Corpus callosum

4

3

2

9

Cortical plate

Stria terminalis

White matter

12

1

Precuneus

Induseum griseum Fornix

10

Layer I


3 6

8 11

5

7

11

172


1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 7 Parietal stratified transitional field Frontal stratified transitional field 8 Posterior striatal neuroepithelium and subventricular zone Callosal glioepithelium 9 Anterolateral striatal neuroepithelium and subventricular zone 10 Anteromedial striatal neuroepithelium and subventricular zone Callosal sling 11 Strionuclear glioepithelium Fornical glioepithelium Parietal neuroepithelium and subventricular zone 12 Subpial granular layer (cortical)



Precentral gyrus

Supramarginal and angular gyri

Lateral fissure Middle frontal gyrus

lob e

Paracentral

Fr on ta l


Insular gyrus

C s pu or

Cingulum

ca

te r

Induseum griseum

Genu

The splenium of the corpus callosum was cut during processing.

n t ri c

4

11 la m

us

a x rni Fo

Th

le

5 11 10

Splenium

Forn ix

Choroid plexus

un

eu

s?

Interhemispheric fissure Splenium rp

Thalamus

us

c a ll o s

5

9

2


Pr ec


Co

3

12


al v e

Pa rie ta ll ob e

Stria terminalis

Claustrum

ule Internal caps Basal ganglia

m su llo

Cin g gyr ulat us e

La

lobule

um

3

11 7

8

1 Stria terminalis

7

6

173



Superior temporal gyrus? Precentral and postcentral gyri Middle and inferior frontal gyri

Frontal lobe Co rp u Cingulum

l na er nt

sul

e

Thalamus

12

5

Dorsal complex Ven tr a l co m p le x

1


callosu m

Occipital lobe?

Precuneus Cingulate gyrus (retrosplenial area)

6 4 9

Layer I The splenium of the corpus callosum was cut during processing.

s rpu Co

or te r i Pos plex co m

10

11

Anterior complex

13


Lateral ventricle

Splenium

5 4

2

cap

Lateral ventricle

Septum


Parietal lobe

Claustrum

I

a ngli


Choroid plexus

Splenium

m osu all sc

Cingulate gyrus

3

Late fissu ral re

Paracentral lobule

a al g as

Supramarginal and angular gyri

Temporal lobe

I ns u l a r g y r u s

B


Lateral fissure

Genu

1 2 3 4 5 6 7

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 8 Parietal stratified transitional field Frontal neuroepithelium and subventricular zone 9 Posterior sriatal neuroepithelium and subventricular zone Frontal stratified transitional field 10 Anterolateral striatal neuroepithelium and subventricular zone Callosal glioepithelium 11 Anteromedial striatal neuroepithelium and subventricular zone Callosal sling 12 Strionuclear glioepithelium Fornical glioepithelium 13 Septal glioepithelium/ependyma Parietal neuroepithelium and subventricular zone 14 Subpial granular layer (cortical)

14

8 7

174



1 2 3 4 5 6 7 8 9

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 10 Parietal/temporal stratified transitional field Frontal neuroepithelium and subventricular zone 11 Alvear glioepithelium Frontal stratified transitional field 12 Subgranular zone (dentate) Callosal glioepithelium 13 Posterior striatal neuroepithelium and subventricular zone Fornical glioepithelium 14 Anterolateral striatal neuroepithelium and subventricular zone Parahippocampal neuroepithelium, subventricular 15 Anteromedial striatal neuroepithelium and subventricular zone zone, and stratified transitional field 16 Strionuclear neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone 17 Septal glioepithelium/ependyma Occipital stratified transitional field Parietal/temporal neuroepithelium and subventricular zone 18 Subpial granular layer (cortical) Callosal glioepithelium

Frontal lobe

gyrus ular Ins trum Claus

I nt

Cingulum

Ci ng ula te gy ru s



4

I nt

Basal ganglia

Lateral ventricle


ern al c

Supramarginal and angular gyri?

Temporal lobe

ral Late ure s s fi

ap

s ul

17

e(

an

ca al ern

ps

Thalamus

t. )

Anterior complex

Dorsal complex

Layer I

co mp lex

Calcarine sulcus

Cuneus

Precuneus

Corpus Cingulate gyrus callosum (retrosplenial area) (splenium)

11

Posterior complex

Ve ntr al

2

6

7

8

White matter

Dark area is an artifact of mounting medium crystallization

Occipital lobe

5

Cortical plate


Superior parietal lobule?

Parietal lobe

Choroid plexus Hippocampus


Habenula

Third ventricle

Lateral ventricle

) st. po e( ul



Septum

Middle and inferior frontal gyri


3

1 14 15 16 18

13

12

10

9

175

PLATE 117


16

Anterolateral striatal neuroepithelium and subventricular zone (infiltrated by the rostral migratory stream) Accumbent neuroepithelium and subventricular zone (infiltrated by the rostral migratory stream)


17


15






Temporal lobe

l era Lat sure s fi

r ar gy sul In

Frontal lobe

us

Nucleus accumbens



um ustr Cla

ia ngl a g al as

4

Anterior complex

Putamen

13 17

12 6

Po comsterior plex

White matter

15

Globus pallidus

Ve nt ra lc om pl ex

Lat eral ven tric le Parahippocampal gyrus

Cuneus

Calcarine sulcus

Occipital lobe

Parieto-occipital sulcus Pineal gland

ePrctum te tro- n en ia s C ed leu m uc n


2

1

Thalamus

Third ventricle

16 3

Hippocampus

Bed nuc. of stria terminalis Hypothalamus

Subc allos al ar ea


Choroid plexus

Pr ec un eu s

zone, and stratified transitional field Occipital neuroepithelium and subventricular zone


B

1 2 3 4 5 6 7 8 9

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 10 Temporal stratified transitional field Frontal neuroepithelium and subventricular zone 11 Alvear glioepithelium Frontal stratified transitional field 12 Subgranular zone (dentate) Callosal glioepithelium 13 Lateral migratory stream (cortical) Fornical glioepithelium 14 Posterior striatal neuroepithelium and subventricular zone Parahippocampal neuroepithelium, subventricular

5

al isu yv x r a e im rt Pr co

11 14

10

9

8 7

176



1 2 3 4 5 6 7 8

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 9 Temporal neuroepithelium and subventricular zone Frontal neuroepithelium and subventricular zone 10 Temporal stratified transitional field Frontal stratified transitional field 11 Alvear glioepithelium Callosal glioepithelium 12 Subgranular zone (dentate) Fornical glioepithelium 13 Lateral migratory stream (cortical) Parahippocampal neuroepithelium, subventricular 14 Posterior striatal neuroepithelium and subventricular zone zone, and stratified transitional field Accumbent neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone 15 (infiltrated by the rostral migratory stream) Occipital stratified transitional field 16 Subpial granular layer (cortical)

Middle temporal gyrus Superior temporal gyrus

ta Pu

ga al

N acc ucl Sub um eus call be osal ns area


Hypothalamus

Dark area is an artifact of mounting medium crystallization

La


te r

al v ent

r ic

le

Cuneus

Calcarine sulcus

15

Anterior complex

Ve nt ra lc om pl ex

1

Superior colliculus

12 6

l ua vis ry ex a im rt Pr co

5

White matter Damaged areas in section

Choroid plexus

Po comsterior plex

Cortical plate

2


otr n en ia s C ed leu m uc n

3

lia ng

Hippocampus

Occipital lobe

Third ventricle

4

Layer I

n me

Midbrain tectum


strum Clau

G pa lob lli us du s In ter na lc ap su le


r us r gy ula s In

Frontal lobe

Ba s


Temporal lobe

l era Lat sure s i f

Th al am us



11 13

14

10

9

7

8

16

177


See detail of brain core in Plates 137A and B. Middle temporal gyrus

Superior temporal gyrus Inferior temporal gyrus Inferior frontal gyrus

N acc ucl um eus be Sub ns call osal area

4

15

3 Cortical plate

2

1

Hippo- Choroid campus plexus

Th al am us

ga al

lia ng

Hypothalamus

Third ventricle

Subthalamic nucleus

Globus pallidus Put ame n

12 6

al v ent r ic le

Occipital lobe

l ua vis ry ex a t im r Pr co

7

8

Posterior complex

5

White matter

13

te r

Calcarine sulcus

Superior colliculus Ve nt ra lc om pl ex

La


Midbrain tectum


Layer I

rum

st Clau n e ta m Pu

In ter na lc bt ap ha su la m le us

Frontal lobe

Su


r us r gy ula s In

Ba s


Temporal lobe

l era Lat sure fis

Preoptic area

1 2 3 4 5 6 7 8

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 9 Temporal neuroepithelium and subventricular zone Frontal neuroepithelium and subventricular zone 10 Temporal stratified transitional field Frontal stratified transitional field 11 Alvear glioepithelium Callosal glioepithelium 12 Subgranular zone (dentate) Fornical glioepithelium 13 Lateral migratory stream (cortical) Parahippocampal neuroepithelium, subventricular 14 Posterior striatal neuroepithelium and subventricular zone zone, and stratified transitional field Accumbent neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone 15 (infiltrated by the rostral migratory stream) Occipital stratified transitional field 16 Subpial granular layer (cortical)

14

11

9 10

16

178

PLATE 120




Lateral fissure Orbital gyrus

ure iss

la m

us

bs tan

al ar ea

3

ha bt

Third ventricle

le su ap lc na t er In

Subthalamic nucleus

Put ame n


Midbrain

12 12

al v ent r ic le

Occipital lobe

Tectum

Hypothalamus

Globus pallidus

2

te r


Tegmentum

Red nucleus

1 Layer I

Su


Nucleus accumbens

allos

La

s

Subc

mu ala Th

Frontal lobe

Choroid plexus

Hippocampus

An ter tia i or inn co om m in a ta

m

Orbital gyrus

Temporal lobe

Endopiriform nucleus?

Su


1 2 3 4 5 6 7

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (intermingled with the 8 Temporal neuroepithelium and subventricular zone accumbent neuroepithelium and subventricular zone) 9 Temporal stratified transitional field Frontal neuroepithelium and subventricular zone 10 Alvear glioepithelium Frontal stratified transitional field Fornical glioepithelium 11 Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular 12 Lateral migratory stream (cortical) zone, and stratified transitional field 13 Posterior striatal neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone Occipital stratified transitional field 14 Subpial granular layer (cortical)

Preoptic area


Superior colliculus Cerebral aqueduct

11

Posterior complex

6

5

4 10 13

9

8

7

14

179

PLATE 121 1 2 3 4 5 6 7

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream 8 Temporal neuroepithelium and subventricular zone Frontal neuroepithelium and subventricular zone 9 Temporal stratified transitional field Frontal stratified transitional field 10 Alvear glioepithelium Fornical glioepithelium 11 Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular 12 Lateral migratory stream (cortical) zone, and stratified transitional field Occipital neuroepithelium and subventricular zone 13 Posterior striatal neuroepithelium and subventricular zone Occipital stratified transitional field 14 Subpial granular layer (cortical)




Temporal lobe


Lateral fissure

Choroid plexus

Orbital gyrus

Op tic t Cer ebr act al pe d

Frontal Primary olfactory lobe cortex (piriform)


r

Subcallos al area

cle un

Hypothalamus

Red nucleus

Subthalamic nucleus

Cortical plate

Put am en

4

Thalamus (posterior complex)

ia nt a ta at bs in Su nom in

1

White matter

12 Damaged areas in section Dark area is an artifact of mounting medium crystallization

al

Lateral occipital gyri

ve nt r ic le

Occipital lobe

Tectum

6

Cerebral aqueduct

Inferior colliculus Substantia nigra

Olfactory tubercle

2

Fusiform gyrus?

ter

Midbrain Tegmentum

Third ventricle

3 Layer I


Amygdala

Preoptic area

Orbital gyrus

La

Hippocampus

13

7

11 5

10 8

9

14

180

PLATE 122


5 6 7



Temporal lobe Lateral fissure



Hippocampus

Amygdala


Optic tract

Gyrus rect us

cle un ed lp

Tegmentum

Substantia nigra

C

White matter Damaged areas in section

11

13

x

Cortical plate

le mp

1

5

3

Inferior colliculus

6

10 4

Central nucleus

7

13 12 14

ve nt r ic le

Tectum

III

al co eci

al

Occipital lobe

Cerebral aqueduct

Third ventricle Olfactory tubercle

Layer I

Fusiform gyrus?

ter

Midbrain

Red nucleus

Hypothalamus

2

La


Orbital gyri

Frontal lobe


Lateral ventricle

Ce re br a

4

om

1 2 3

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream 8 Temporal stratified transitional field Frontal stratified transitional field 9 Alvear glioepithelium Fornical glioepithelium 10 Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular 11 Lateral migratory stream (cortical) zone, and stratified transitional field Occipital neuroepithelium and subventricular zone 12 Posterior striatal neuroepithelium and subventricular zone Occipital stratified transitional field 13 Amygdaloid glioepithelium/ependyma Temporal neuroepithelium and subventricular zone 14 Subpial granular layer (cortical)

o rt i c


9

8

181

PLATE 123



Temporal lobe Endopiriform nucleus

Lateral fissure Primary olfactory cortex (piriform)

gdala Amy

Orbital gyri

Frontal lobe Interhemispheric fissure

Optic tract

Gyrus rect us

us mp Parahippocampal gyrus cle un ed lp

Hypothalamus

Cortical plate

Olfactory peduncle

1

Corticomecial complex

White matter


10

12

Substantia nigra

2

Fusiform gyrus?

Lateral ventricle

13

Midbrain

Tegmentum

Third ventricle

Layer I


icle entr lv

Lat era

4 5 6 7

Hippoca

3

Ce re br a

1 2


Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream 8 Alvear glioepithelium Fornical glioepithelium 9 Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular 10 Lateral migratory stream (cortical) zone, and stratified transitional field Occipital neuroepithelium and subventricular zone 11 Posterior striatal neuroepithelium and subventricular zone 12 Amygdaloid glioepithelium/ependyma Occipital stratified transitional field Temporal neuroepithelium and subventricular zone 13 External germinal layer (cerebellum) Temporal stratified transitional field 14 Subpial granular layer (cortical)

Tectum

Occipital lobe Cerebellum (vermis)

Cerebral aqueduct Inferior colliculus

4 5

9 3 14

Central nucleus

11

8 7

6

182

PLATE 124


Temporal lobe icle entr lv us

Lateral fissure

gdala Amy

Orbital gyri

Frontal lobe G yr


Optic chiasm

us re ctu s

Hypothalamus

Olfactory peduncle

ncle edu lp ra b re

1

9

11

Midbrain

Tegmentum

Fusiform gyrus?

Lat ventreral icle

Tectum Cerebellum (vermis)

Third ventricle

Primary olfactory cortex (piriform) Damaged areas in section

e


Substantia nigra

Corticomedial complex teral Basola lex comp


mp

Hippoca

Lat era


Remnants of the germinal matrix, migratory streams, and transitional fields 1 Rostral migratory stream 7 Alvear glioepithelium neuroepithelium, subventricular 8 Subgranular zone (dentate gyrus) 2 Parahippocampal zone, and stratified transitional field 3 Occipital neuroepithelium and subventricular zone 9 Lateral migratory stream (cortical) 10 Amygdaloid glioepithelium/ependyma 4 Occipital stratified transitional field 5 Temporal neuroepithelium and subventricular zone 11 External germinal layer (cerebellum) 12 Subpial granular layer (cortical) 6 Temporal stratified transitional field

C


10

8 7

Central nucleus

6

Cerebral aqueduct

2

5 12 13

3

4

Occipital lobe

183


Remnants of the germinal matrix, migratory streams, and transitional fields 1 Rostral migratory stream 6 Alvear glioepithelium neuroepithelium, subventricular 7 Subgranular zone (dentate) 2 Parahippocampal zone, and stratified transitional field 8 Lateral migratory stream (cortical) 3 Occipital stratified transitional field 9 Amygdaloid glioepithelium/ependyma 4 Temporal neuroepithelium and subventricular zone 10 External germinal layer (cerebellum) 5 Temporal stratified transitional field 11 Subpial granular layer (cortical)



Temporal lobe

Lateral ventricle

Amygdala

aParampal p oc ru s p i h gy

Cerebral peduncle

Uncus Olfactory peduncle

Pons

Pontine gray

Fusiform gyrus?

Hemisphere

9 teral Basola lex comp

Entorhinal cortex

6


7

Occipital lobe

CEREBELLUM Vermis

1

3

10


11

Fourth ventricle

2


4

White matter

5

184


Remnants of the germinal matrix, migratory streams, and transitional fields neuroepithelium and 4 Lateral migratory stream (cortical) 1 Parahippocampal subventricular zone 5 Amygdaloid glioepithelium/ependyma Parahippocampal stratified transitional field 2 6 External germinal layer (cerebellum) 3 Alvear glioepithelium 7 Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 144A and B. Middle temporal gyrus


Temporal lobe Parahippocampal gyrus Uncus

Hemisphere

Entorhinal cortex Pontine gray Transpontine corticofugal tract

Pons

3

4

Occipital lobe?

CEREBELLUM

Lat era l ve ntri cle


Fusiform gyrus?

Vermis

6


7

Fourth ventricle


2

1

White matter

185




2



Uncus

Hemisphere


Entorhinal cortex

Pons

Fourth ventricle


Deep nuclei

Pontine gray

Occipita Vermis

CEREBELLUM


Temporal lobe Damaged areas in section

l lobe

1 2

186

PLATE 128 GW30 Horizontal, CR 260 mm, Y187-65

Remnants of the germinal matrix, migratory streams, and transitional fields 1 External germinal layer (cerebellum) 2 Germinal trigone 3 Subpial granular layer (cortical)

Level 17: Section 1081 See detail of brain core and cerebellum in Plates 146A and B.

Hemisphere Middle cerebellar peduncle De ep nu cle i

Pontine gray

Entorhinal cortex

Fourth ventricle

Pons


2

Occipital lobe

Vermis

1

CEREBELLUM Vestibular nuclear complex

Temporal lobe



Level 18: Section 1121 See high magnification view of this section in Plates 147A and B.

Middle cerebellar peduncle Nerve V

Pontine gray Transpontine corticofugal tract

Hemisphere De ep nu cle i Medulla

Pons

Vermis

Fourth ventricle Choroid plexus

CEREBELLUM

1

3

187

PLATE 129 Remnants of the germinal matrix, migratory streams, and transitional fields 1 External germinal layer (cerebellum)


Level 19: Section 1161 See high magnification view in Plates 148A and B.


Hemisphere


Pons

Medulla Vermis

Pontine gray

Transpontine corticofugal tract Inferior olive

CEREBELLUM

Fourth ventricle

1

Choroid plexus

Level 20: Section 1201 See high magnification view in Plates 149A and B (left panel). Flocculus

Inferior olive Hemisphere Pyramid Pontine gray

Medulla

Fourth ventricle Vermis

Corticospinal tract Inferior cerebellar peduncle Choroid plexus

CEREBELLUM

1

188


Remnants of the germinal matrix, migratory streams, and transitional fields 1 External germinal layer (cerebellum)


See high magnification view in Plates 149A and B (right panel).

Choroid plexus Inferior cerebellar peduncle and spinocerebellar tracts Inferior olive Pyramid Corticospinal tract

Hemisphere

Medulla

1 Solitary nuclear complex

CEREBELLUM



See high magnification view in Plates 150A and B (left panel).

Lateral reticular nucleus Inferior olive Pyramid Corticospinal tract Hypoglossal nucleus (XII)

Medulla

1

Central canal Gracile nucleus Cuneate nucleus Spinal nucleus and tract (V) CEREBELLUM (hemisphere)

189

PLATE 131 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2


Dorsal funicular myelination gliosis Ventral funicular myelination gliosis


See high magnification view in Plates 150A and B (middle panel).

Central canal

1

Pyramid

Gracile nucleus Cuneate nucleus

Corticospinal tract

Spinal nucleus and tract (V)

Medulla


See high magnification view in Plates 150A and B (right panel). Pyramidal decussation

Central canal

1

Pyramid

Gracile fasciculus Corticospinal tract

2

Cuneate fasciculus Spinal nucleus and tract (V) Lateral corticospinal tract

Medulla

190



191

PLATE 132B Germinal and transitional structures in italics Insular gyrus

Claustrum External capsule

Internal capsule (anterior limb)

C auda

Caudate (head)

C

in

gu

lu

m

ia

l ina term

Str

Septal glioepithelium/ ependyma

Stria medullaris

ix rn Fo

Lateral ventricle Choroid plexus

Forrn Fo niixx

Callosal sling


cleus?

Induseum griseum

Cave of the septum

Fornix Antero-

DORSAL D COMPLEX orsol nuc ater Ve leu al ant ntral s e rio n u VE cle r us NT RA LC Ventral IC OM UL lateral PLE AR X nucleus B Stria

Do r nu som cle ed us ial


Torn and shifted area in the section Induseum griseum Corpus callosum (splenium)

For nix CENTRAL COMPLEX: Central lateral nucleus

THALAMUS

T

BASAL GANGLIA

D CO OR MP SAL LE X

ANTERIOR COMPLEX Anteroventral nucleus

RE

dorsal nucleus liu m th e z o n e i p r oe e u r r i c u la n l t Anteromedial ia t a e n S tr d s u b v Strionuclear an l glioepithelium tera a l o er Ant

terminalis

E LT

: Retic ula

Putamen Frontal neuroepithelium and subventricular zone

Cingulum Cingulate gyrus (retrosplenial area)


Lateral septal nu


is

THALAMUS


Ci ng ulu m

te

Strionuclear glioepithelium (body)

La ter al ven tri cle

Cingulate gyrus Induseum griseum Interhemispheric fissure

Internal capsule (posterior limb)

Putamen

Insular gyrus


Cingulum Callosal glioepithelium Fornical glioepithelium Stem cells of choroid plexus

r nucleus

Strionuclear glioepithelium Stria terminalis Caudate (tail)



Cortical plate

White matter

Layer I

Lateral fissure


Parietal neuroepithelium and subventricular zone

192

PLATE 133A GW30 GW30 Horizontal Horizontal CR CR 260 260 mm mm Y187-65 Y187-65 Level Level 4: Section 521


193


Lateral migratory stream?

apsule External c

Claustrum

sule capimb) l a ern r l Int sterio (po

Claustrum

Putamen



Callosal sling


us Lateral septal nucle

Septal glioepithelium/ependyma Fornical glioepithelium


te r

o

al

Caudate (head)


Lateral migratory stream? Frontal neuroepithelium and subventricular zone Frontal stratified transitional field

Stria terminalis

Lateral fissure

R

BASAL External capsule

DO RS AL

E

N

Induseum griseum

Torn and shifted area in the section OM PL EX

Interhemispheric fissure Corpus callosum (splenium)

DORSAL COMPLEX

C in

E

CO NT R M PL AL CO EX M

gul

um


THALAMUS

PLE

X T ET R A IC L UL CO AR MP LE BE GANGLIA X LT

POSTERIOR COMPLEX

nix For

Fornical glioepithelium Stem cells of choroid plexus

Stria terminalis

Putamen

Claustrum Insular gyrus


Callosal sling

RC


C

An

r la te

ANTERIOR COMPLEX

ulum Cing


PERIVENTRICU LA

V

White matter

Pulvinar

Third ventricle Foramen of Monro

Choroid plexus

Dorsomedial nucleus

Stria medullaris

Fornix

li u m it h e z o n e p e o eu r u la r tal nventric a i r Anteromedial S t su b and


Mammillothalamic Anteroventral tract? nucleus Periventricular nuclei


Cave of the septum

D or Cen s tra nuc ola l la le ter t us al

e

Fornix


Stria terminalis

le s s u e u n tr a l p l Ve ral ca uc la te le u s l n a n nuc r er Int la us ucle ln a er

Re V ti a n e n tr c u n u te r io a l c le r us

lu m s gu ru gy C in te ula ng Ci

La te ra lv en tr icl

Caudate (head)

Lateral ventricle

Stria terminalis

x rni Fo

Inte (an rnal c teri aps or l ule imb )


Lateral migratory stream? Lateral fissure

Caudate (tail)



Parietal/temporal neuroepithelium and subventricular zone Parietal/temporal stratified transitional field

194



195

PLATE 134B Subpial granular layer


Lateral fissure

Insular gyrus

Visual radiation


Lateral migratory stream Layer I


e

I

ti

n

t

lim b Caudate (head)

R

nucleus

Anterior commissure




Anteromedial

ANTERIOR COMPLEX

Habenulo-interpeduncular tract

COMPLEX

Ca (h u d ea a te d)

R

E


Striatal neuroepithelium and subventricular zone

BASAL GANGLIA Externa l capsule

T

N

al

X PLE IVENTRICULA R COM R E DORSAL

E

ter


C

t An

la e ro



Stria medullaris


P

SEPTUM

ix rn Fo



Fasciola cinereum


Third ventricle Medial septal nucleus

Subiculum

Pulvinar

Periventricular nuclei

Dorsal tenia tecta

Strionuclear neuroepithelium and subventricular zone

Dorsomedial nucleus

Lateral ventricle Dentate gyrus Ammon's horn

raPa cular i s c fas ucleu n

Mammillothalamic tract? Anteromedial nucleus

Choroid plexus


Ce

Stria terminalis Anteroventral

ve nt ric le

HIPPOCAMPUS

Ventral le s u u posterolateral s p le nucleus a uc l c a n tr l l Ventral en era us a V t posteromedial n la cle r nucleus e nu leus c c nu ra l

An ter ior

La ter al

Putamen

te

White matter

mb r li o i ter Pos

nt ra l la

E

su le l cap a n r x te

u V la a n e n tr r n u te r io a l c le r us

Cortical plate



m Claustru

T

V I

C

U

E L

N

A

T

R

R

A

B

E

L

L

R

AL

MP

LEX

C O M P L E X

POSTERIOR COMPLEX

Subgranular zone

T Strionuclear glioepithelium

Putamen

Claustrum Lateral migratory stream? Insular gyrus

THALAMUS

CO

Fornix

Alvear glioepithelium Fornical glioepithelium



196



197

PLATE 135B Lateral fissure rus ar gy Insul

m Claustru

en tam u P

le p su a c al ern E xt

In

u c le u s

Third ventricle

TR A

THALAMUS

L C O M PL

N T

R

EX

T

E C

A

I

L

U

Lateral fissure

R

a

ru s

L

A

R

B

C EL

O


M

POSTERIOR COMPLEX

T

Subgranular zone Strionuclear glioepithelium

Putamen Claustru

ar gy

E

ll

BASAL GANGLIA

Diencephalic (thalamic) glioepithelium/ependyma Pre tec tum

EN

ANTERIOR COMPLEX

V

du

ern al c aps ule

Habenulointerpeduncular tract?

ICULAR COMPLEX NTR E IV ER

(in Glo te bu rn s al pa G (e lo se lli xt bu gm d u er s en s na p r y la t) l s a ll m e g id u ina m s en t) Me

Ext

Pineal gland

C

OTH ALA MUS

Posterior commissure

E

HYP

is inal term


In su l

ral n

Periventricular nuclei


t r ia

Nucleus accumbens

nt

m ctu e t e Pr

Parafascicular nucleus

L

Median preoptic nucleus Medial septal nucleus eral eus o Lat nucleus ucl l a t dn sep Be

Caudate (head)



Fornix


Anterolateral striatal neuroepithelium and subventricular zone (infiltrated by the rostral migratory stream)

Pulvinar

te R rn

M

An


s he ft


are a

Nucleus accumbens


UM PT SE

Dorsal tenia tecta Interhemispheric fissure

Subiculum

posterolateral nucleus


ce

osa l

s Ventral

s leu

ra

call

c

Pa

Sub

e issur

Ca u (h e d a te ad)

Co rp (ro us c str allo um su ) m

m r com terio

Lateral ventricle

u

Choroid plexus Dentate gyrus

l l ra ia nt ed Ve rom us ste cle po nu

lim b

le

Lateral ventricle

Ammon's horn

a l Ven i c c ant tral u l a a p e r i r s nuc or leus u Ve n u l e n C en la t tral nu teraral late c le l ral us nu c

ed

u

An ter ior

us ) llid ent a p m na us e g o b nal s l a m i l G ter y ar u s t) (ex ll lid e n l a m s p seg u b l lo a G tern (in t e

P

White matter

HIPPOCAMPUS

b lim r rio te s Po




X

Subpial granular layer Lateral fissure

P

Lateral migratory stream (infiltrates the claustrum and the external capsule)

m

Stria terminalis


Caudate (tail)

Fornix

Alvear glioepithelium Fornical glioepithelium Posterior striatal neuroepithelium and subventricular zone

198



199

PLATE 136B

Primary olfactory cortex (piriform iform))

Cortical plate

m Claustru

sule al cap Extern

us t) lid en l a m na s p seg m i u b l la lo rna G te x (e

a nu teraral cle l us

du

ln uc l

eo pr o- s al hyp area r e t d c La an ami Dorsomedial al nucleus th

Fornix


TRICULAR COMPL EX IVEN ER

R R

B

E

L

CO M PL EX

m ctu ete Pr

T A T

tr e a m

N

l

rus

ory s

Putamen

L

ul

ar gy

ig r a t

m

A

U

ed

Lateral fissure

In su l

ral m

Claustru

C TI

(in Glo te bu rn s al pa se lli gm d u GANGLIA a r y en s la t) G lo m in (ext bus a p ern a l s a llid u egm s e n t) M

BASAL

Ext ern al c aps ule

E

le

CE NT RA L

E

R

sa is? An ular it c n

ANTERIOR COMPLEX

V

us c le b e n s u N um acc

Posterior commissure Third ventricle (pineal recess)

MIDBRAIN TECTUM

Forel's fields


Pineal gland

Diencephalic (hypothalamic) Third glioepithelium/ependyma ventricle

PREOPTIC AREA HYPOTHALAMUS


Optic nerve layer (superior colliculus)


THALAMUS L


X

Ventral tenia tecta Interhemispheric fissure Median preoptic nucleus

Centromedian

Mammillonucleus thalamic tract Anteromedial nucleus Paraventricular nucleus Periventricular nuclei

Superior colliculus

m ctu e t e Pr

C

E

l ar ea

L a te

Ventr al m ed ial

t e ra

fore Media brai n bul ndle ? ic t p

call osa


eus

al p ost ero m

P

Sub

ll

a

ry (in Glo b ter us na pa l s lli eg du m s en In t) R t e et rn al ic ul ca ps ar Ven t u r a nu ante l cl nuc rior leus eu C en Ve tral s la l nt

ac Nu cu cle m us be ns

Me

missure Anterior com

rp (ro us ca s tr llo u m su ) m

Ventr

Dentate gyrus Ammon's horn

Subiculum

Pulvinar

us cle nu

Co

l tra ral Ven olate ter eus p os n u cl

le


s cleu nu ial ed

An te rio rl im b

HIPPOCAMPUS

Po ste rio r

le psu l ca Putamen a n ter Ex

White matter


s Insular gyru

Lateral fissure



O

L

Layer I


lim b


M P

POSTERIOR COMPLEX

Subgranular zone Strionuclear glioepithelium

Fornix



Alvear glioepithelium Fornical glioepithelium Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

200



201

PLATE 137B

Putamen Basal nucleus of Meynert

l ra nt Ve

le

An


L at

rea

e r al h

na i ncer

Forel's fields

Fornix

M PL EX

A

C O MP

T R E

IC

NT

SUBS TA

AR

am

L B E

stre

Putamen Primary olfactory cortex (pirifor iform m))

Lateral fissure

Claustrum

Insular gyrus


Mesencephalic glioepithelium/ependyma Diencephalic (thalamic) glioepithelium/ependyma

T

External ca psule

LE X

POSTERIOR COMPLEX

U L

BASAL GANGLIA ry

Pr et ec tu m

CO

I A IN N O MI

Deep white layer

TR

US

ato

Deep gray layer

THALAMUS L

M

ig r

Middle white layer

Central gray

L

V EN

LA

al m

Middle gray layer

Cerebral aqueduct

RA

HA

ter

Superficial gray layer

MIDBRAIN

NT

NAT A

P

CO T M ER PL IO EX R

BT

La

Optic nerve layer

CE

l le ? d ia Me n bund i a r b fore Ansa lenticularis?

Globus pallidus

Ext ern al c aps ule

Superior colliculus Zonal layer

TRICULAR COMPL EX IVEAN ER N

SU

Nucleus accumbens


us cle s eu


Periventricula r nuclei

HYPOTHALAMUS





Dentate gyrus


TECTUM



Pulvinar

us

Choroid plexus Lateral ventricle Ammon's horn

Subiculum

Diencephalic (hypothalamic) Third glioepithelium/ependyma ventricle




y pothalamic area

Dorsomedial nucleus

Zo

us

Ansa lenticularis? fore Media brai n bul ndle ?

llosal a

ta

c

or p (r u s os ca tr ll um os ) um

HIPPOCAMPUS


a

Nucleus accumbens

C

Subca

ent)

te

le psu l ca a n er Ext

Int (an erna ter l ca ior ps lim ule b)

egm al as n r te m i n

um ia t str

Glo ommisrior su r bus e pa M e d u llidu lla s r y (ex G l (in lo ter bus na pa l s lli eg du Ce m s reb en ra t) l pe Su b th du n u a la cle mi ncl e c

White matter

Ventral tenia tecta

us

Central lateral al nu nu Ce n tr cl nucomed le u ia n s

Cortical plate

C la

Pr et ec tu m

Primary olfactory cortex (piriform iform))

e sul cap l a m rn tru Exte

R eticular n Ventral m uc edi

Lateral fissure

Layer I



Subpial granular layer s r gyru Insula

In (po tern ste al c rio ap r l sul im e b)



Fornix



Subgranular zone Alvear glioepithelium Fornical glioepithelium Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

202



203

PLATE 138B Lateral migratory stream

le um su str l cap u a b) Cl erna lim t al x r E po


L a t e ra


a c are lami tha o l hy p

Fornix

Periventricular nucleus Lamina terminalis

Subcallosal area

Preoptic recess

us sc ni em ll ia Red nucleus

H ab



Reticular formation

ed Dorsomedial nucleus


AL

AM

OM

TA INA

r e r io u r te iss An mm co

s du lli pa us ob Gl

INN

e

Insular gyrus

Pr et ec tu m

MIDBRAIN

THALAMUS POSTERIOR COMPLEX

BASAL GANGLIA Clau

Deep gray layer

Cerebral aqueduct

Deep white layer Subcommissural organ


US

Putamen Primary olfactory cortex (piriform)

Middle white layer

TECTUM

TIA

r issu ral f

Late Lateral migratory stream

TH

Red nucleus

B

TAN

Ve nt ra ls tr ia tu m

Middle gray layer

Central gray

TEGMENTUM

SU

S U BS

rcle ctory tube Olfa

Nucleus accumbens


Superficial gray layer


HYPOTHALAMUS



Optic nerve layer


Ventral tenia tecta


Superior colliculus Zonal layer

tum tec e r P

enu l culao-inter r tr p e d u act nInterpeduncular nucleus?

Third ventricle

PREOPTIC AREA


Zona incerta

lp

Medial forebrain bundle?



m y la in ar

Choroid plexus Lateral ventricle Ammon's horn Dentate gyrus

HIPPOCAMPUS

M

White matter (orbital gyrus)

a lenticularis Ans

Cortical plate (orbital gyrus)

Ventral striatum

ed un cle

go (h o n a l b a r iz o n d n ta o f B l lim ro b) ca

Nucleus accumbens

D ia

Islands of Calleja

en Putam

a


(in the ventrolateral frontal lobe)

te m

Su bt n u h a la c le m i us c

Endopirirorm nucleus

e( ur iss

Ce reb ra

White matter

An ter

ior

Cortical plate


co m m

Lateral fissure

M G ed (in lo b ul ter u s l p na a l s e llid u gm s en t)

Layer I



osterior limb) psule (p nal ca Inter Meyer's loop (visual radiatio n)

(infiltrates the claustrum, endopiriform nucleus and the external capsule)

strumExternal ca psule


Fornix



Parahippocampal stratified transitional field Parahippocampal neuroepithelium and subventricular zone Subgranular zone Alvear glioepithelium Fornical glioepithelium Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

204



205

PLATE 139B b) lim al

m

Ammon's horn

or com mi ssu re (

te

(infiltrates the endopiriform nucleus)


Dentate gyrus

t

Periventricular nucleus Lamina terminalis

Su b nu thal cle am us ic

ia l

hi

of

the


rc ol

White matter lic

Inferior colliculus

ul

Central

Subcommissural organ Cerebral aqueduct Raphe nuclear complex

MIDBRAIN cu s

cle

n is

ac

un


Strionuclear glioepithelium Lateral St A geniculate ria N TI ter body A m in IN In V ali ter N O en s na M tr a lc IN l s a p AT tri su A at le um (p os ter ior E xt ern al c lim aps u le b) Basal nucleus of Meynert


le m

lp

tr

t

ia l

ra

ed

us

Medial longitudinal gray fasciculus Oculomotor nuclear complex (III)

ed

reb

c SU

BS

Parahippocampal stratified transitional field

T


r e r i o ur t e i ss An m m co

Lateral fissure Lateral migratory stream

rio

un

TEGMENTUM

i

Central nucleus? (amygdala)


infe

Reticular formation

nu c u lo -in la r te tra rpe ct du n pe d

Ce

Medial nucleus? (amygdala)

t


(in the ventrolateral frontal lobe)

um


p

Olfactory tubercle

Cortical plate

s cu

Red nucleus

be

HYPOTHALAMUS

O

White matter (orbital gyrus)

ed

X)

ac

M

Cortical plate (orbital gyrus)

Fornix Fo rni Sup x ram am m are i l l a a ry

M

le m

n

is

Layer I

TECTUM


Ha

area

Third ventricle

PREOPTIC AREA

Subcallosal area

Br


cul

Preoptic recess

hyp o th a la m ic

cl eu s ter In Ventral tegmental decussation



Sexually dimorphic nucleus?

eral

r ula n tic atio e R rm fo

nu

ct

L at


lp

ac tr

Tuberomammillary nucleus


TE TH RI AL OR AM C O US M PL E

Substantia nigra

Ce reb ra

c

ti

p

O

ra


ed un cle

Medial nucleus? (amygdala)

ry t cto lfa l o

Islands of Calleja

OS

ar

ra

Olfactory tubercle

(P

Central nucleus (amygdala)

te

Su

AMYGDALA La

ulu m

nix For

Stria terminalis

bic


HIPPOCAMPUS

Ventral striatum

Ante ri




Caudate (tail)

po r


Parahippocampal neuroepithelium and subventricular zone

Alvear glioepithelium Temporal neuroepithelium and subventricular zone Caudate (tail)

Temporal stratified transitional field Posterior striatal neuroepithelium and subventricular zone

206



207

PLATE 140B Internal capsule (posterior limb) Anterior commissure (temporal limb)

Amygdaloid Alvear glioepithelium glioepithelium/ ependyma


(infiltrates the endopiriform nucleus)

DORSAL HIPPOCAMPUS


AMYGDALA Basolateral complex


Amygdalo-hippocampal area



Optic tract

HYPOTHALAMUS Supraoptic nucleus

Arcuate nucleus




Periventricular nucleus

le nc u ed

Medial lemniscus, spinocephalic, and trigemino-thalamic tracts

Substantia nigra


Red nucleus


Olfactory sulcus

area

Olfactory peduncle

ct

P ri cor m ary te x o lfa (p ir c to ifor ry m)

Lat er a

lp

Basolateral complex Strionuclear glioepithelium Central nucleus


un

Cerebral aqueduct

Central gray

Raphe nuclear complex Oculomotor nuclear complex (III) Medial longitudinal fasciculus Central

Reticular formation

nucleus

MIDBRAIN

Brachium of the inferior colliculus Nucleus of the lateral lemniscus (dorsal) Lateral lemniscus

cle



e ul ) ps b ca lim al r rn io te ter In pos (


ra

or y act ry olf to )

ed


r ia lis S t in a m te r

AMYGDALA

tr a

r e r io ur te i s s A n mm co

Lateral fissure


c fa rm ol fo y piri r a ( im ex Endopirirorm Pr ort nucleus c

l

reb

Orbital gyrus

teral olfacto r y tract La

po ip -h ea lo ar da al yg p m m A ca

Nucleus of the lateral olfactory tract

Ce


De n t

Choroid plexus

Ca uda te ( tail External capsule )


Inferior colliculus

TEGMENTUM

Lateral Ventral mammillary nucleus tegmental

Cortical plate

TECTUM

InterInterpeduncular peduncular nucleus fossa Medial Oculomotor mammillary nerve? (III) nucleus

PREOPTIC AREA Diencephalic (hypothalamic) glioepithelium/ependyma

Layer III Layer II Layer I

Reticular formation


Forn ix


Gyrus rectus

Layer IV


Lamina terminalis

White matter


Layers V-VI

Ce re br al

p


ia/for n ix

Stria terminalis




Central nucleus

HI VE PP N OC TR AMAL PU S F im b r



a te


gyr us

A m mon's

ho r

n

Lateral ventricle


208



209

PLATE 141B

Central nucleus


Lateral ventricle

AMYGDALA HI VE PP N OC TR AMAL PU S

Stria terminalis


Ce re br al

p

Orbital gyrus

Medial olfactory tract Lateral tuberal nucleus Optic


tract

Gyrus rectus

Supraoptic nucleus


Arcuate Ventro- nucleus medial Medial mammillary nucleus

PREOPTIC AREA


Suprachiasmatic nucleus Third ventricle (preoptic recess)

nucleus

Diencephalic (hypothalamic) glioepithelium/ependyma Third ventricle (infundibular recess)

a pact com Pars

le us

uc

Red nucleus

t e rior olfactory n

e ncl

Co r co tico m m pl ed ex ia l

An

Glioepithelium (optic tract) Am y camgda p a lo -h i l a pp rea o-


Intercalated masses

Basolateral complex Stria terminalis

Central nucleus

ior re ter issu Anmm co

Lateral migratory stream Amygdaloid glioepithelium/ependyma

CEREBELLUM

Central gray Central nucleus

MIDBRAIN

Lateral lemniscus Nucleus of the lateral lemniscus (dorsal)

Occipital stratified transitional field Occipital neuroepithelium and subventricular zone


HI D PP OR De O C SA nta te g AM L yru s PU S A m m o n ' s ho r n



Subgranular zone

ix rn /fo ia br m Fi

Lateral fissure

y or ) ct m fa for l o i y ir a r (p m tex i P r cor Endopirirorm nucleus


Trochlear nucleus (IV)

Cortical plate

Vermis

Cerebral aqueduct



AMYGDALA

Culmen (IV-V)

TECTUM

HYPOTHALAMUS

Inferior colliculus Dorsal tegmental nucleus

InterInterpeduncular peduncular nucleus fossa Oculomotor nerve? (III) S u p erior cerebe

White matter

Layer I

Parabrachial nucleus Central tegmental tract


Occipital gyrus



Reticular formation

Substantia nigra

TEGMENTUM

Olfactory peduncle


le nc u lata ed Pars reticu

pedu llar

Olfactory sulcus

Fusiform gyrus


Basolateral complex



Lateral ventricle


Choroid plexus

Caudate (tail)




210



211



AMYGDALA

Lateral ventric le

Basolateral complex



Olfa ct

ory s ulcu s

Arcuate nucleus

Substantia nigra


IP V E PO NT CA RA M L PU S

un

cle

Trochlear Medial nucleus (IV) longitudinal fasciculus


MIDBRAIN



e at s cin ulu Un scic fa

Central nucleus

Am

mo

n's


Fusiform gyrus

D en t



ho r n Choroid plexus




CEREBELLUM


Lateral lemniscus

Subgranular zone

Central nucleus

Cerebral aqueduct

Culmen (IV-V)

S AL PU RS AM DO OC yrus P g IP ate H

Prim cort ary ol ex ( facto piri formry )

Intercalated masses

Stria terminalis

lp

AMYGDALA

ed

Vermis

TECTUM

ra

Basolateral complex

H

Central gray

C e nu ntra cle l us

reb

Orbital gyrus

Superior Dorsal tegcerebellar peduncle mental nucleus

TEGMENTUM

Ce




Glioepithelium (optic chiasm)?

Anterior olfactory nucleus


Reticular formation

ucleus ln

Oculomotor nerve? (III)

HYPOTHALAMUS Olfactory peduncle

ta ompac Pars c

ach br ia

Medial mammillary nucleus

Occipital gyrus

or eri s I n f lic u lu col

Gyrus rectus


Optic chiasm

Medial olfactory tract


Lateral ventricle


le nc u ed ulata Pars retic

Par a

Supraoptic nucleus

Ce re br al

p







212



213



(entering the basolateral complex)


A mmon's ho

Latera l ventr icle

iculum Sub



En

to

rh

i na lc

White matter Layers V-VI

us gyr l a mp a c po hip a r Pa

Sub icu lu m

AM Y GDA LA

rn

c o rte

E n t o r h i n al



x

Cortical plate

Trochlear nerve? (IV)

ex

a br re e C

l

d pe

Hemisphere

cle un

y ra eg tin n Po

Oculomotor nerve? (III)

C

ra

lp

ed u

ncle

Subgranular zone

Subiculum

CentralisVermis (III) Culmen (IV-V) Cen gra tral y

Fourth ventricle Pontine glioepithelium/ependyma

Anterior lobe (HIV-HV ) Superior medullary velum Medial longitudinal fasciculus

VENTRAL HIPPOCAMPUS

Basolateral complex


r n t a te g y

AMYGDALA

De


Am

Fusiform gyrus

us

mo

n's

ho r n

Uncinate fasciculus




CEREBELLUM Occipital gyrus

Reticular formation

M TU N


er eb


nucleus (V) Dorsal tegmental nucleus Superior cerebellar Para b rac nucl hial peduncle eu s

E N AI GM BR TE ID M

Ventral tegmental area Substantia Pars compacta nigra Pars reticulata

Tear in secti o n

PONS Mesencephalic


al cortex hin or t En

Layer III Layer II Layer I

Lateral lemniscus


ort

Layer IV

214



215


White matter


Entorhinal cortical plate


Primary fissure

Layers V-VI Layer IV (lamina dessicans) Layer III

r E nto

Layer II (stellate cell islands) Layer I

hi n

or al c

tex

Hemisphere Occipital gyrus Tea r in

P O N S

Pontine gray


nuc

le u


s


Lingula (I-II)

Centralis (III)

Vermis

Declive (VI)




c o r t e x

Motor nucleus (VII) Principal sensory nucleus (V)

CEREBELLUM


Anterior lobe (HIV-HV )

Primary fissure


Fusiform gyrus


Culmen (IV-V)

Inferior cerebellar peduncle?

Alvear glioepithelium VENTRAL HIPPOCAMPUS

Fourth ventricle

Reticular formation

t e g m e n t al


sec tio n Locus coeruleus Mesencephalic nucleus (V) Tear in se ction Dorsal longitudinal fasciculus

Ret icula r

Pontocerebellar fibers (decussation

Subiculum


Lateral lemniscus Medial lemniscus, spinocephalic, and trigemino-thalamic tracts


t o r h i n a E n l

Layers V-VI Layer IV Neocortical plate Layer III Layer II Layer I

Parahippocampal neuroepithelium and subventricular zone Parahippocampal stratified transitional field

Simplex lobule (HVI) Subpial granular layer

216



217


CEREBELLUM Primary fissure

Hemisphere

Middle cerebellar

le

t e g m e n t al


erebellar ped or c eri un cle


Fastigial nucleus



le u

s


Reticular formation

Centralis Culmen (III) (IV-V)

Declive (VI)


Medial lemniscus, spinocephalic, and trigemino-thalamic tracts Motor nucleus (VII) Motor nucleus (V) Nerve V Principal sensory nucleus (V) Lateral lemniscus


Primary fissure



Vermis

EI CL NU EP DE

nuc


Mi dd le c er eb e

Dentate nucleus

Fourth ventricle

Ret icula r


ellar peduncle cereb


p Su

P O N S

Pontine gray

or feri In


c un ed rp lla

n tio sec in ar Te


peduncle

Crus I, ansiform lobule (HVIIA)


Folium (VIIa)

218



219


CEREBELLUM Primary fissure


ntal nucleus


ucleus


La ter al


lear n

Superior olive complex Vestibular nuclear Motor complex nucleus (VII) Nerve VII (genu)

Abducens nucleus (VI) Dorsal longitudinal fasciculus


Hemisphere

le

Dentate nucleus

S uperior cerebellar


e peduncl

Choroid plexus

Germinal trigone

Fourth ventricle

e g me Reticular t

ion n sect Tear i

Pontine gray

P O N S

Medial lemniscus and trapezoid body


lem ni sc us

l coch

unc

cer Inf ebe erio llar r ped unc le

ed r p a l l Middle cerebe Dorsa





Nodulus (X)

Vermis

Uvula (IX)

Pyramis Tuber Folium (VIII) (VIIa) (VIIa)


Reticular formation


Superior olive complex

M Nerve V

id

dle

Vestibular Motor nucleus (VII) nuclear complex Spinal nucleus and tract (V) Late ral l Inferior emn iscu cerebellar s peduncle Dorsal cochlear nucleus

cer

ebe

llar

pedun

Fourth ventricle (lateral recess) Superior cereb ellar peduncle

DEEP NUCLEI

cle

Anterior lobe (HIV-HV ) Simplex lobule (HVI)


Primary fissure


220



221

PLATE 147B Germinal and transitional structures in italics C ru s I, Simplex lobule (HVI)

le bu lo

Pa ram biv edian ent lob r al ul lob e (H ule VI (H IB) VI II) a n d

Primary fissure

ter

P O N S

ce

rebel

lar

Fourth ventricle

e


pe

du

eb cl ceredun p leus

n

cl

e

Choroid plexus


Crus II, ansiform lobule (HVIIA)

c r nu hlea c o c sal Dor

Nodulus (X)

Uvula (IX)

Pyramis (VIII)

Vermis

Tuber (VIIa)


Reticular formation

Motor Vestibular Superior nucleus (VII) nuclear olive complex omplex us La cle V) u ter ln t( al ina rac lem Sp nd t ni a sc or us eri ar Inf ell e

M

dl




Trapezoid body


Vestibular nuclear Motor complex nucleus (VII)


Medial lemniscus



id

Hemisphere

Dentate nucleus


La

Pontine gray

sal coch Dor In cereferior p e d b e lla r unc le

al

lem

ni

sc

us

r

eus u cl

id

r

lla

n

rn lea

M

e dl

ce

e eb

du

)

Nerve V (root)

pe

r ferio d In uncles n a ed dle Mid bellar p cere

e cl

IA

Nerve V (boundary cap)

VI (H

Anterior lobe (HIV-HV)

Nerve V

CEREBELLUM

an sifo rm

Floccular peduncle


Germinal trigone

DEEP NUCLEI

Flocculus

Middle and Inferior cerebellar peduncles

d ) an B I I (HV II) bule le (HVI o l n u ia b med al lo Para biventr Crus I, ansiform lobule (HVIIA)


222



223

PLATE 148B Germinal and transitional structures in italics C rus

re

r io

r

fe

In

e dl

id M

P O N S

cle

ce


Reticular formation

m

Medial longitudinal fasciculus and tectospinal tract Dorsal longitudinal fasciculus

Fourth ventricle

Medial le

Inferior olive complex

In

Paraflocculus (HIX)

Choroid plexus

Hypoglossal nucleus (XII)?

s scu ni


External germinal layer Crus II, ansiform lobule (HVIIA)

Choroid plexus




Hemisphere

re

Solitary nucleus Inferior olive (capsule) Prepositus nucleus

Medial lemniscus

Pontine gray

lla

cle

CEREBELLUM

be

pedun

ce

be

r lla

e r p du n

us ucle

Do rs al Ventral cochlea co rn c hl uc l ear n eu s

Nerve VIII (root)

sifor m lo bule (H V I IA )

Pa ram biv edian ent lob ral ul lob e (H ule VI (H IB) VI II) and

Flocculus (HX)

Nerve VII (?)

I, a n

Nodulus (X)

Uvula (IX)

Pyramis (VIII)

Vermis


Reticular formation

fe

or

nucleus r i Spinal and tract (V)

MEDULLA Paraflocculus (HIX)

ce re

b

e ll

ar

ped

u n cle

Nerve IX (root)

Flocculus (HX)

Choroid plexus

nd ) a B II I) HV VII ( ule le (H b o u n l l lob a i a d me ventr a r Pa bi




224





225


Section 1241

CE RE BE LL UM

Inferior cerebellar peduncle Cuneate nucleus

and tract

PONS

Pyramid

Raphe nuclear complex Medial lemniscus


Corticospinal tract Principal nucleus Medial accessory nucleus


Infer Cuneate ior c nucleus Sp ereb ino el cer la r e l c p eb ell e d u nts a r trac

Flocculus (HX)

Vermis Uvula (IX)

Fourth ventricle

*Arcuate nucleus (medulla)

Medial longitudinal fasciculus and tectospinal tract Dorsal accessory nucleus



Reticular formation

Principal nucleus

le obu l n ia medVIIB) a r Pa (H

Hemisphere

Medial lemniscus

Solitary nucleus and tract

Medial accessory nucleus

Paraflocculus (HIX)

ule l lob a r t n ) Bive (HVIII

Corticospinal tract




Medial lemniscus (arcuate fibers)



Nucleus ambiguus

Nerve X

Nodulus (X)


Reticular formation

Choroid plexus


Biv ent ral lob ule (HV III) Paraflocculus (HIX)


Pyramid



Fourth ventricle

Dorsal sensory nucleus (X) Dorsal motor nucleus (X) Prepositus nucleus Hypoglossal nucleus (XII)

Nucleus ambiguus Nucleus of Roller

Paraflocculus (HIX)

an Cr sifo us I (H rm l I, VI obu IA le )

llar ebe cer cle r o eri un Inf ped Solitary nucleus

Choroid plexus

s II, Cru lobule form ) ansi VIIA

Spinocerebellar tracts Middle cerebellar peduncle Basal pontine gray



(H ) IIB HV e( ul lob

MEDULLA

s II, Cru lobule form ) ansi (HVIIA

Flocculus (HX)

) IIB HV e( ul lob

Biv ent ral lob ule (HV III)

ian ed m ra Pa

ian ed m ra Pa

CEREBELLUM

Lateral reticular nucleus Spinal nucleus and tract (V)

MEDULLA

Area postrema Dorsal motor nucleus (X) Dorsal sensory nucleus (X) Gracile fasciculus Gracile nucleus Cuneate nucleus External cuneate nucleus Paraflocculus (HIX)

ule b o ll tra III) n ve V Bi (H

an Cr sifo us I (H rm l I, VI obu IA le )

Section 1201

e ul b o l an B) i ed II m HV a r ( Pa

*The arcuate nucleus in the medulla may contain neurons from the Raphe migration.

Hemisphere


226

PLATE 150A GW30 Horizontal CR 260 mm Y187-65

Level 22: Section 1281 Level 23: Section 1351 Level 24: Section 1391




227


Section 1281 L OW E R M E D U L L A Spinocerebellar tracts External cuneate nucleus

Spinocephalic tract Spinal nucleus and tract (V)


eate Cun leus c nu

Gracile nucleus

Gracile fasciculus

Dorsal sensory nucleus (X) Central canal (medulla/spinal cord)


Reticular formation

Accessory nucleus (XI)

Ventral funicular myelination gliosis


Glioepithelium/ependyma Glioepithelium/ependyma

Dorsal motor nucleus (X)

Dorsal funicular myelination gliosis

*The arcuate nucleus in the medulla may contain neurons from the Raphe migration.

Central cervical nucleus

Glioepithelium/ependyma P de yra cu m ssa ida tio l n

trac t(

Substantia gelatinosa


V)

Reticular formation

Spin al

Lateral cervical nucleus

Cuneate fasciculus



Lateral reticular nucleus

Central canal (medulla/spinal cord)

Commissural nucleus (X)

Lissauer's tract

Spinocephalic tract Pyramid al in (corticosp) tract

Gracile nucleus

Motoneuron columns (spinal cord)




Medial lemniscus

Central canal (medulla/spinal cord)

Spinocephalic tract

e fasciculus acil Gr

id l m ina ra sp Py tico ct) or ra (c t

Medial accessory olive nucleus


Cuneate nucleus

us c le nu t ry rac lita d t So an or ot m X) al ( rs us e Do ucl ssal ) n lo II og (X yp s H cleu nu


Section 1391 MEDULLA/ SPINAL CORD

Cu ne

iculus asc ef at


Section 1351 MEDULLA/ SPINAL CORD

Gracile fasciculus

Gracile nucleus

Cuneate fasciculus

La cortic teral osp tract inal

Medial longitudinal fasciculus and tectospinal tract Spinocerebellar tracts

Dorsal funicular myelination gliosis

228

PART PARTVII: VII:

GW29 GW29 CORONAL CORONAL

gy ru s

Postc ent ra l

us

gy ru ulc s ls

nt ra

Prec ent ra Ce l

rio rf r Su pe

NTAL LOB FRO E

Insular gyrus

p Su

mp r te o i er

or a

y lg

te M id d l e

PO

I n f e rio r t

RAL

ru

mp

o

e mp

LOBE

ITAL LO CIP BE OC

Orbital gyri

ra

Angular gyrus al occipital gyri t er La

te La

re ssu i f l

ma pra u S

BE LO

tal gyrus fron r o i fer n I

M

The approximate cutting plane of this brain is indicated in Figure 10 (facing page) with lines superimposed on the GW30 brain from the Larroche (1967) series. This brain is cut perpendicular to the longitudinal axis of the cerebral hemispheres between the frontal and occipital poles and is remarkably even in the medial/lateral plane (both temporal poles appear in Level 3, Section 621). As in all other specimens, the sections chosen for illustration are spaced closer together to show small structures in the diencephalon, midbrain, pons, and medulla. Illustrated sections are spaced farther apart when they contain only large brain structures, such as the cerebral cortex, basal ganglia, and cerebellum. Photographs of 20 different Nissl-stained sections (Levels 1-20) are shown at low magnification in Plates 151-170. Different areas of the cerebral cortex are shown at very high magnification in Plates 171-174. The core of the brain and the cerebellum are shown at high magnification in companion Plates 175AB-189AB for Levels 3-18.

i

TE

This specimen is case number W-14-59 (Perinatal RPSL) in the Yakovlev Collection. A female fetus was prematurely stillborn after intrauterine asphyxia. Autopsy notes include a subdural hemorrhage, and there is a hemorrhage in the striatal germinal matrix on the left side of many sections. However, the remainder of the brain appears normal and is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). It was cut in the coronal plane in 35-µm and 15-µm thick sections. Since there is no available photograph of this brain before it was embedded and cut, the photograph of the lateral view of a GW30 brain that Larroche published in 1967 (Figure 9) is used.

M

dd

rio lob r pa ule rie tal

inal gyru rg s

us gyr l ta s on yru g al nt o fr le

PARACENTRAL LOBULE PAR IE TA Su pe L

s

gy ral

ru

l gy o ra

s

rus

Cerebellar hemisphere Medulla Spinal cord

Figure 9. Lateral view of a GW30 brain with major structures in the cerebral hemispheres labeled. This is the same as Figure 7 repeated here for convenience. (From the photographic series of J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

229

GW29 CORONAL SECTION PLANES LEVEL NUMBER 1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

1621

1521

1021 1061 1101 1161 1201 1261 1301 1361

981

701 741 781 821 861 901

621

501

321

Y14-59 contains the same immature structures shown in the GW30 Horizontal specimen. A densely staining neuroepithelium/ subventricular zone is present and presumably generating neocortical interneurons in all lobes of the cerebral cortex. The same thickness variations between the occipital and other lobes of the cerebral cortex are still there. Remnants of migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields. Many neurons, glia, and their mitotic precursor cells are still migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Within the lateral parts of the cerebral cortex, definite streams of neurons and glia are in the lateral migratory stream that percolates through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus. These cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a large neuroepithelium/subventricular zone overlying the striatum and nucleus accumbens where neurons are being generated; at least three subdivisions (anteromedial, anterolateral, and posterior) can be distinguished in the striatal part. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Other structures in the telencephalon, such as the septum, fornix, and Ammon’s horn have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle.

SECTION NUMBER Figure 10. Lateral view of the same GW30 brain shown in Figure 9 with the approximate locations and cutting angle of the sections of Y14-59. (From the photographic series of J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 248.)

Most of the structures in the diencephalon appear to be settled and are maturing, but the third ventricle is lined by a more densely staining glioepithelium/ependyma than in the GW37 specimens. A convoluted glioepithelium/ependyma lines the cerebral aqueduct in the midbrain that continues into the anterior fourth ventricle. A smooth glioepithelium/ependyma lines the fourth ventricle through the posterior pons. A slightly convoluted glioepithelium/ependyma lines the floor of the fourth ventricle near the midline in the medulla. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is actively producing basket, stellate, and granule cells. The cerebellar cortex itself shows less definition between hemispheric lobules. The germinal trigone is at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia may still be originating here.

230



Frontal neuroepithelium and subventricular zone Frontal stratified transitional field

Interhemispheric fissure Superior frontal gyrus


2

Frontal lobe


Cingulate gyrus

1

White matter


1 2 Orbital gyri

Superior rostral gyrus Inferior rostral gyrus

2

231


Remnants of the germinal matrix, migratory streams, and transitional fields 1 Frontal neuroepithelium and subventricular zone 2 Frontal stratified transitional field 3 Callosal glioepithelium neuroepithelium and subventricular zone (intermingled with 4 Frontal the source of the rostral migratory stream) 5 Rostral migratory stream 6 Anterolateral striatal neuroepithelium and subventricular zone




Frontal lobe

Lateral ventricle

2

Cingulum


Cingulate gyrus Inferior frontal gyrus

Caudate (head)

3 1

Induseum griseum


Internal capsule (anterior limb) Putamen Basal ganglia

Insular gyrus Claustrum External capsule

6

Tenia tecta (dorsal)

3 4

Subcallosal area

2

Orbital gyri Damaged areas in section

Olfactory sulcus Gyrus rectus Olfactory peduncle

5

Lateral fissure

Frontal lobe

232



Frontal neuroepithelium and subventricular zone Frontal stratified transitional field

7 8 9 10 11

Callosal glioepithelium Callosal sling Fornical glioepithelium Rostral migratory stream


Accumbent neuroepithelium and subventricular zone (intermingled with the rostral migratory stream and the frontal neuroepithelium/subventricular zone) Anteromedial striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Lateral migratory stream (cortical) Subpial granular layer (cortical)


Corpus callosum (body) Layer I Middle frontal gyrus

Frontal lobe

Cingulum Cingulate gyrus

Lateral ventricle

Caudate (head)

9

5 Fornix

Septum

Lateral septal nucleus Medial septal nucleus Claustrum External capsule Insular gyrus Superior and middle temporal gyri

1

3

4


White matter

2

Induseum griseum

Internal capsule (anterior limb) Putamen

Cortical plate

8

Frontal lobe

Basal ganglia

7

Lateral fissure

10 2

Temporal pole

Nucleus accumbens Orbital gyrus Subcallosal area Gyrus rectus Olfactory peduncle

6 Olfactory sulcus

11

233


See detail of brain core in Plates 175A and B. Interhemispheric fissure


Frontal lobe



u rp

ven

5


Preoptic area


1 9

8

Septum

7 sa

re issu omm or c i r e Ant

3

c cu

Lateral fissure

10

N ucleu

Globus pallidus

Fornix leus Latera l septal nuc

cle tri

gyr us

s

Putamen

4

su m

Basal ganglia


m bens

Olfactory tubercle

Inferior temporal gyrus Primary olfactory cortex (piriform) Fusiform gyrus Damaged areas in section

al

) ad he le e( su ap lc na ter


ter

ll o

at


In

Claustrum

ud


Ca

External capsule

ca

Layer I

2

Induseum griseum

Co

La

Insular

1 2 3 4 5

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 6 Rostral migratory stream 7 Accumbent neuroepithelium and subventricular zone Frontal stratified transitional field 8 Anteromedial striatal neuroepithelium and subventricular zone Callosal glioepithelium 9 Anterolateral striatal neuroepithelium and subventricular zone Callosal sling 10 Lateral migratory stream (cortical) Fornical glioepithelium 11 Subpial granular layer (cortical)

Parolfactory gyrus/uncus

6


11

Islands of Calleja

Temporal lobe

234


1 2 3 4 5

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 6 Strionuclear glioepithelium Frontal stratified transitional field 7 Anteromedial striatal neuroepithelium and subventricular zone Callosal glioepithelium 8 Anterolateral striatal neuroepithelium and subventricular zone Callosal sling 9 Lateral migratory stream (cortical) Fornical glioepithelium 10 Subpial granular layer (cortical)




Cingulum


Cingulate gyrus

Co

Induseum griseum

r

pu


Insular gyr us

Claustrum


sc a

L at l l o s u m era lv

icle entr

) ad le (he su ap ate lc ud na Ca ter In

External capsule

Septum

2

Bed nuc. of stria terminalis Anterior Globus commissure pallidus

Fornix


Anterior amygdaloid area?

Fusiform gyrus Damaged areas in section

Parolfactory/parahippocampal gyrus

Lateral fissure

Preoptic area

cto Olfa

le berc r y tu ary olfa Prim

Optic chiasm

Third ventricle (preoptic recess) Diagonal band of Broca (horizontal limb)

10

ctory


9

6

tex cor


7

Basal ganglia



Frontal lobe

1 4 3 8 5

Fornix

Putamen

White matter

Temporal lobe

235





Layer I

Frontal lobe

Cingulum Middle frontal gyrus

Cingulate gyrus Lateral ventricle

Induseum griseum

Co

r

pu

ud

Ca

External capsule

le ) su ad he cap al rn te In

e(

sc all o s u

Foramen of Monro

m en

Globus pallidus

Anterior commissure Basal nucleus of Meynert


Central nucleus





m

3

4 5 Fornix

Septum

6


2 1 8

7

Bed nucleus of stria terminalis

P u ta


at

Claustrum


Insular gyr us

1 2 3 4 5

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 6 Strionuclear glioepithelium Frontal stratified transitional field 7 Anteromedial striatal neuroepithelium and subventricular zone 8 Anterolateral striatal neuroepithelium and subventricular zone Callosal glioepithelium 9 Lateral migratory stream (cortical) Callosal sling stratified transitional field (intermingled 10 Parahippocampal Fornical glioepithelium with the amygdaloid glioepithelium/ependyma)

9

Fornix Supraoptic nucleus


Hypothalamus Optic tract

Basolateral complex

Fusiform gyrus Parolfactory/parahippocampal gyrus

Lateral fissure

Basal ganglia

A m yg

9 d a la Temporal lobe

Third ventricle Arcuate nucleus?

10

236


1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 7 Anteromedial striatal neuroepithelium and subventricular zone neuroepithelium, subventricular zone, Frontal stratified transitional field 8 Parahippocampal and stratified transitional field neuroepithelium and subventricular zone (intermingled Callosal glioepithelium 9 Temporal with the amygdaloid glioepithelium/ependyma) Callosal sling 10 Amygdaloid glioepithelium/ependyma Fornical glioepithelium 11 Lateral migratory stream (cortical) Strionuclear glioepithelium 12 Subpial granular layer (cortical)


Superior frontal gyrus?

Layer I

Frontal lobe

Cingulum Middle frontal gyrus

White matter

Cingulate gyrus

2 1

Lateral ventricle

Induseum griseum

C

or pu


m en

7

6 Lateral fissure

x

ple

P u ta

om

Insular gyr us

3

Thalamus

Globus pallidus Substantia innominata

Basal ganglia

11

Third ventricle Fornix

Co

r c o t ic o m me Central pl d e x ia nucleus l


Basolateral complex


Fornix

4 5

or c

Anterior commissure

m

teri



osu

ar ul t ic lt Re be


all

An

Claustrum

e ) ul ad ps he ca e( at al ud rn te Ca In

External capsule

sc

Cortical plate

Parolfactory/parahippocampal gyrus

Optic tract Hypothalamus

8 12

Arcuate nucleus Ventromedial nucleus Entorhinal cortex

Am ygd ala

10

9

11

Temporal lobe

237



See this area of cortex in Plate 171.



Frontal lobe Precentral gyrus

Cingulum

Claustrum

Corpu

e dat Cautail) (

External capsule

m en P u ta

le p su l ca rna

Anterior complex Reticular belt Ventral complex Periventricular complex

3 5 4

Thalamus Lateral fissure

Basal ganglia

Third ventricle

Globus pallidus

Anterior commissure


Forel's fields Cerebral Optic peduncle tract Co Hypothalamus Central r c o tic o nucleus m me pl d Fornix e x ia l Basolateral complex Lateral ventricle


s c a ll o su m

Fornix

In te



2 1

Induseum griseum

Postcentral gyrus

White matter

2

Cingulate gyrus

Lateral ventricle

Cortical plate

Hippocampus

le bu l lo tr a cen ra Pa

Central sulcus

Insular gyr us

1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal/paracentral neuroepithelium and subventricular zone 7 Alvear glioepithelium neuroepithelium, subventricular zone, Frontal/paracentral stratified transitional field 8 Parahippocampal and stratified transitional field Callosal glioepithelium 9 Temporal neuroepithelium and subventricular zone Strionuclear glioepithelium 10 Temporal stratified transitional field Anteromedial/posterior striatal neuroepithelium and 11 Lateral migratory stream (cortical) subventricular zone Amygdaloid glioepithelium/ependyma 12 Subpial granular layer (cortical)

Arcuate nucleus Ventromedial nucleus

Temporal lobe

Amygdala

6

7 12

Entorhinal cortex (in parahippocampal gyrus)

9 8

11 10

238

PLATE 159


1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Paracentral neuroepithelium and subventricular zone 7 Alvear glioepithelium neuroepithelium, subventricular zone, Paracentral stratified transitional field 8 Parahippocampal and stratified transitional field Callosal glioepithelium 9 Temporal neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone 10 Temporal stratified transitional field Strionuclear glioepithelium 11 Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma 12 Subpial granular layer (cortical)


Interhemispheric fissure Precentral gyrus


Central sulcus

White matter Cingulate gyrus Lateral ventricle

Postcentral gyrus

Induseum griseum

External capsule



Reticular belt Ventral complex

P u ta

m en

Insular gyr us Anterior commissure Uncinate fasciculus

Globus pallidus Optic tract

Amygdala Caudate (tail)

Lateral ventricle

5

Fornix Anterior complex

Claustrum


3

Corpus callosum

Dorsal complex Periventricular complex

Thalamus


Subthalamus

7

Basal ganglia

11 Amygdala

Hi pp oc am pu s

8

Mammillary body

Entorhinal cortex

Lateral fissure

Third ventricle

Ammon's horn

Fusiform gyrus

Stria terminalis

Stria medullaris

Su bt Forel's nu halam fields cle us ic Fornix C Hypope ereb du ra thalamus nc l le

m ulu bic Su

4

2 1

le bu

Caudate (tail)

Internal capsule

l lo ra nt ce ra Pa

2

Cingulum

12

6

4

10 9

Temporal lobe

239


See detail of brain core in Plates 181A and B. Interhemispheric fissure Layer I Precentral gyrus Cortical plate

Central sulcus

le bu l lo ra nt ce ra Pa

Postcentral gyrus Cingulum Cingulate gyrus

External capsule

Supramarginal gyrus

Insular gyr us



Optic tract

Internal capsule

Lateral geniculate body Zona incerta

4 Parietal lobe

Stria medullaris

Lateral fissure

Thalamus Central complex

Oculomotor nuclear complex Red nucleus

a gr ni ia le nt ta nc du pe al br re

bs

Ce

Su

o

rn

Dorsal complex

Ventral complex

Dentate gyrus

h n's

Lateral ventricle

A m mo


Caudate (tail)

5

Fornix

1

Stria terminalis

Basal ganglia

Globus pallidus

3

Corpus callosum

Caudate (tail)

Claustrum

White matter

2

Induseum griseum

Lateral ventricle

Put am en

1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Paracentral neuroepithelium and subventricular zone 7 Subgranular zone (dentate) neuroepithelium, subventricular zone, Paracentral stratified transitional field 8 Parahippocampal and stratified transitional field Callosal glioepithelium 9 Temporal neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone 10 Temporal stratified transitional field Strionuclear glioepithelium 11 Lateral migratory stream (cortical) Alvear glioepithelium 12 Subpial granular layer (cortical)

Subiculum

Midbrain tegmentum Interpeduncular nucleus

8

Fusiform gyrus Entorhinal cortex (in parahippocampal gyrus) Transpontine corticofugal tract Pontine gray Middle cerebellar peduncle

11

Third ventricle

Pons

12

Hippocampus

6 4 7

Temporal lobe

10 9

240


1 2 3 4 5 6

Remnants of the germinal matrix, migratory streams, and transitional fields Paracentral/parietal neuroepithelium and subventricular zone 7 Subgranular zone (dentate) neuroepithelium, subventricular zone, Paracentral/parietal stratified transitional field 8 Parahippocampal and stratified transitional field Callosal glioepithelium 9 Temporal neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone 10 Temporal stratified transitional field Strionuclear glioepithelium 11 Lateral migratory stream (cortical) Alvear glioepithelium 12 Subpial granular layer (cortical)


Layer I

Precentral gyrus

Cortical plate

Central sulcus

Pa ra ce nt ra l

Postcentral gyrus

External capsule


Internal capsule


Corpus callosum

Caudate (tail)

Ventral complex

h 's on


n

a gr ni ia e nt ncl ta bs edu Su ral p reb Ce

Amm

or

Subiculum

Interpeduncular fossa Pontine gray Middle cerebellar peduncle Transpontine corticofugal tract Pontocerebellar fibers (decussation)

Stria terminalis

Lateral fissure

Thalamus

Third ventricle


7 6 4

12

Temporal lobe

10

Hippocampus

Pons

11

Basal ganglia

Midbrain tegmentum

Fusiform gyrus Entorhinal cortex (in parahippocampal gyrus)

Parietal lobe

4

Stria medullaris

Dorsal complex

Lateral Central Central geniculate complex Medial body geniculate Optic body Oculomotor tract nuclear complex Zona incerta Dentate Red gyrus nucleus

Lateral ventricle

5

Fornix

I n su l ar g y ru s Put am en

Supramarginal gyrus

1

3

Induseum griseum

Caudate (head)

lob ul e

2

Cingulum Cingulate gyrus Lateral ventricle

White matter

8

9

241

PLATE 162 Remnants of the germinal matrix, migratory streams, and transitional fields Paracentral/parietal neuroepithelium and subventricular zone Paracentral/parietal stratified transitional field Callosal glioepithelium Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Alvear glioepithelium

7 8 9 10 11 12

Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Mesencephalic glioepithelium/ependyma Subpial granular layer (cortical)

See detail of brain core in Plates 183A and B. Precentral gyrus Central sulcus



Postcentral gyrus

Paracentral lobule Cingulum

Supramarginal gyrus

Induseum griseum

Lateral ventricle Caudate (tail)


Amm

Lateral geniculate Medial body geniculate Cerebral aqueduct body Dentate Central gyrus Subiculum gray

h 's on

or

n


Stria terminalis

Thalamus

Basal ganglia

7 6

11 Midbrain tegmentum

Raphe nuclear complex Cerebral peduncle Medial lemniscus Reticular tegmental nucleus Raphe nuclear complex Middle cerebellar peduncle Pontine gray Transpontine corticofugal tract Pontocerebellar fibers (decussation)

Pons

4

Hippocampus

tex

r

Fusiform gyrus

r h i n al c o

Superior cerebellar peduncle (decussation)

Lateral fissure

12

8

Temporal lobe

10

to


Parietal lobe

4


Optic tract


Dorsal complex

Pretectum

Internal capsule

Lateral ventricle

5


Reticular belt Ventral complex

Caudate (tail)

3

Fornix

Putamen


1

Corpus callosum

External capsule

White matter

2

Cingulate gyrus

En

1 2 3 4 5 6


9

242



7 8 9 10 11 12

Paracentral/parietal neuroepithelium and subventricular zone Paracentral/parietal stratified transitional field Callosal glioepithelium Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Alvear glioepithelium

Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Mesencephalic glioepithelium/ependyma Subpial granular layer (cortical)

See detail of brain core in Plates 184A and B. InterhemiPrecentral gyrus spheric fissure Central sulcus (fusing)

12

Postcentral gyrus

Layer I

Paracentral lobule


Cingulum

Supramarginal gyrus

3

Induseum griseum

External capsule

Corpus callosum


5

Inte rna l ca psu le

Fornix Putamen

Reticular belt Posterior complex

Dentate gyrus Ammon's horn Lateral ventricle

Subiculum

Central gray


Cerebral aqueduct


Fusiform gyrus

Temporal lobe

Medial Lateral geniculate geniculate body body

m tu ec et Pr



11

Superior cerebellar peduncle Medial lemniscus Raphe nuclear complex

Pons

Middle cerebellar peduncle Transpontine corticofugal tract Pontine gray

6 4 10

Trochlear nuc. (IV)

Tegmentum

Nerve V

7

Hippocampus

8

Midbrain

Reticular tegmental nucleus Pontocerebellar fibers (decussation)

Lateral fissure

Stria terminalis

Thalamus Brachium of the inferior colliculus

Parietal lobe

4

Dorsal complex

Caudate (tail)


1

Lateral ventricle Caudate (head)


2

Cingulate gyrus

12

9

243



Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Mesencephalic glioepithelium/ependyma Raphe migration External germinal layer (cerebellum) Subpial granular layer (cortical)


See detail of brain core and cerebellum in Plates 185A and B. Interhemispheric fissure 13

Postcentral gyrus

Precentral gyrus


Supramarginal gyrus

Paracentral lobule

Layer I

Cingulum

2

Cingulate gyrus


Reticular belt Posterior complex Subiculum Parahippocampal gyrus

Parietal lobe Stria terminalis

Thalamus Midbrain

Fusiform gyrus

m c tu Te


Lateral ventricle

Dentate gyrus Ammon's horn

1

4

5

nix Forrn

Ex


3

Corpus callosum

Lateral ventricle

Caudate (tail)

Hippocampus

7

6

Lateral fissure

Temporal lobe

4

Central gray

11

Cerebral aqueduct

Abducens nucleus (VI)?

Raphe nuclear complex Lateral lemniscus Medial lemniscus

Tegmentum

Cerebellum (hemisphere) Pontine gray


Induseum griseum

S co u p e lli r i cu or lu s

Paracentral/parietal neuroepithelium and subventricular zone Paracentral/parietal stratified transitional field Callosal glioepithelium Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Alvear glioepithelium Subgranular zone (dentate)

Inte terna l rna l ca capsu psu le le

1 2 3 4 5 6 7

Superior olive complex Ventral cochlear nucleus Raphe nuclear complex Inferior olive complex Pyramid (corticospinal tract) Arcuate nucleus (medulla)

14 13

Pons


10

8

12 Medulla

Nerve V

9

244

PLATE 165 9 10 11 12 13 14 15

Paracentral/parietal neuroepithelium and subventricular zone Paracentral/parietal stratified transitional field Callosal glioepithelium Posterior striatal neuroepithelium and subventricular zone Strionuclear neuroepithelium/glioepithelium Alvear glioepithelium Subgranular zone (dentate) Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Postcentral gyrus


Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Mesencephalic glioepithelium/ependyma Isthmal and pontine glioepithelium/ependyma Raphe migration External germinal layer (cerebellum) Subpial granular layer (cortical) Precentral gyrus? Central sulcus?


Postcentral gyrus?

Paracentral lobule

15

Layer I

Cingulum

Cortical plate

Cingulate gyrus

Supramarginal gyrus

White matter

2

Induseum griseum Lateral ventricle n ix For


1 3

Corpus callosum Hippocampal commissure

Dentate gyrus Subiculum Parahippocampal gyrus Ammon's horn

4

Parietal lobe Internal capsule

Caudate (tail)

Thalamus

Midbrain

Superior colliculus Cerebral aqueduct Central gray Inferior colliculus

5 7

Hippocampus

4

9

Tectum

Fusiform gyrus

Brachium of the inferior colliculus Lateral lemniscus

14

Motor nuc. (V)

la r tic u io n Rermat fo

14

Principal sensory and spinal nucleus (V) Dorsal cochlear nucleus? Ventral cochlear nucleus? Damaged areas in section

ar ul on tic ati e R rm fo


Pons

13

Mesencephalic nuc. (V) Locus coeruleus

8 Temporal lobe

m ) llu re be he e re sp iddl llar i Ce em cMeredbue ncle pe (h


6

11 12

us


Motor nuc. (VII)

Medulla


Choroid plexus Medial lemniscus

Lateral fissure

Stria terminalis

Isthm

1 2 3 4 5 6 7 8

Fourth ventricle



Exter nal ca psule



10 15

245

PLATE 166 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5 6 7

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Callosal glioepithelium Fimbrial glioepithelium Posterior striatal neuroepithelium and subventricular zone Alvear glioepithelium Subgranular zone (dentate)

8 9 10 11 12 13 14


Occipital neuroepithelium and subventricular zone Occipital stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Pontine and medullary glioepithelium/ependyma External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 187A and B. Postcentral gyrus?

Interhemispheric fissure Superior parietal lobule

Parietal lobe


Precuneus

Cingulum Supramarginal/ angular gyri

Cingulate gyrus

2

s ca rpu Co

Induseum griseum

ll o

3

s

um

( s ple n

i u m)

Hippocampal commissure Subiculum

Occipital lobe

Midbrain tectum Fusiform gyrus?

h orn

8

Inferior colliculus

Cerebellum (vermis)


Pons

Ventral cochlear nucleus Prepositus nucleus Spinal nucleus and tract (V) Raphe nuclear complex Choroid plexus Inferior olive complex

12

Fourth ventricle

Temporal lobe

6

9

13 m ) llu re be he re isp Ce em (h

Middle cerebellar peduncle Dorsal cochlear nucleus

7


Medulla ar ul on tic ati Re rm fo

Lateral fissure

5

s

Choroid plexus


4

Dentate gyrus

Occipital gyrus


Lateral ventricle

Fimbria

Hippocampus Parahippocampal gyrus

1

n' mo Am


White matter

Precuneus

Medial lemniscus Pyramid (corticospinal tract)

10 11

14

246




7 8 9 10 11 12

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Callosal glioepithelium Fimbrial glioepithelium Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Medullary glioepithelium/ependyma Germinal trigone (cerebellum) External germinal layer (cerebellum) Subpial granular layer (cortical)

Precuneus






12

Cingulum

Angular gyrus

2

Cingulate gyrus

3

Induseum griseum Corpus callosum (splenium)

Cuneus?


l

Lateral ventricle

7


Fasciola cinereum

10

Dorsal motor nucleus (X)

Fourth Vestibular ventricle nuclear complex

Solitary nucleus and tract

uc

9

Cuneate nucleus Spinal nucleus and tract (V)

le i

Raphe nuclear complex Lateral reticular nucleus

Choroid plexus

Inferior olive complex Medial lemniscus Pyramid (corticospinal tract)

6

m llu


Ce re be

Temporal lobe

11

Cerebellum (vermis)

m ) llu re be he re sp i Ce em n p (h ee (d

Fastigial nucleus Interpositus nucleus Dentate nucleus Middle and inferior cerebellar peduncles

8

5

l ita ip cc e O lob

it a cip ri c O gy

1

4



Parietal lobe

ria mb Fi

s ru a) gy re te ial a a ul en ng pl Ci tros e (r

Choroid plexus


White matter

Precuneus

Medulla

11

)

Inferior cerebellar peduncle and spinocerebellar tracts

Reticular formation

247

PLATE 168 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3 4 5

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Callosal glioepithelium Occipital neuroepithelium and subventricular zone Occipital stratified transitional field

6 7 8 9 10


Temporal neuroepithelium and subventricular zone Temporal stratified transitional field External germinal layer (cerebellum) Spinomedullary glioepithelium/ependyma Subpial granular layer (cortical)



Precuneus



White matter

Precuneus

2 Angular gyrus

Parietal lobe

10 Cingulate gyrus (retrosplenial area)

Lateral ventricle

1

3

Choroid plexus

Middle temporal gyrus?

Cuneus?


O

p cci

it a

l

r gy

4

i

5 Cerebellum (vermis)

8

Fastigial nucleus

m llu

Dentate nucleus

Ce re be

uc


Area postrema External cuneate nucleus Cuneate nucleus Spinal nucleus and tract (V) Raphe nuclear complex Accessory nucleus (XI) Pyramidal decussation Pyramid (corticospinal tract)

7 Temporal lobe

Occipital lobe

m ) llu re be he re p s i n Ce em p ee (h (d


6

le i

8

)

Fourth ventricle

Medulla

Choroid plexus

Inferior cerebellar peduncle and spinocerebellar tracts Central canal surrounded by Reticular formation Spinocephalic tract?

9

248



5 6 7 8


Temporal neuroepithelium and subventricular zone? Temporal stratified transitional field? External germinal layer (cerebellum) Subpial granular layer (cortical)


Precuneus

Layer I

Parietal lobe


Angular gyrus Parietooccipital sulcus

Cuneus

Middle temporal gyrus? Lateral ventricle

1 2

8

Calcarine fissure


4

5 Temporal 6 lobe?

3 Occipital lobe

Occipital gyri Cerebellum (vermis)

C (he erebe m i llu sp h m ere )

7

7

249

PLATE 170 Remnants of the germinal matrix, migratory streams, and transitional fields 1 2 3

Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Occipital neuroepithelium and subventricular zone

4 5 6


Occipital stratified transitional field External germinal layer (cerebellum) Subpial granular layer (cortical)

See the primary visual cortex from a nearby section in Plate 174.


6

Precuneus



White matter

Angular gyrus

2

Primary visual cortex Parietooccipital sulcus

Cuneus

Lateral ventricle (occipital recess)

Parietal lobe

1

Calcarine fissure

Lingula?

4


3

3

Occipital lobe Occipital gyri


5

4

250

PLATE 171 GW29 Coronal CR 260 mm, Y14-59 Level 8: Section 861 FRONTAL CORTEX


I I II


II

III III


IV IV V V VI VI


251

PLATE 172 GW29 Coronal CR 260 mm, Y14-59 Level 14: Section 1161

I

CORTEX OF THE PRECENTRAL GYRUS (Primary motor cortex)

II



II

III

III

IV

IV

V


Large neurons are Betz pyramidal cells

V VI VI VII VII White matter

252

PLATE 173 GW29 Coronal CR 260 mm, Y14-59 Level 17: Section 1301 PARIETAL CORTEX Latest arriving cells

I

I

II

II

III

III

IV IV See the entire section in Plate 167.

V V

VI

VI VII

White matter

VII

253

PLATE 174 GW29 Coronal CR 260 mm, Y14-59 Posterior to Level 20: Section 1681 STRIATE (Primary visual) CORTEX See level 20 in Plate 170.


I

I

II

II III

III

IVa

IVa Band of Gennari

IVb

IVb

IVc

IVc

V

V

VI

VI


254



255

PLATE 175B Germinal and transitional structures in italics Layer I Cortical plate White matter


C in


gul um

La te

ra

Ca

lv

Cave of the septum

tal nucleus L ater al sep


rn

n) Fornix (colu m

Exte

y cort or t ac

min ata

Olfactory tubercle

olf

Fusiform gyrus

be

ns

Lateral migratory stream Large island of Calleja

Islands of Calleja

(infiltrates endopiriform nucleus and penetrates piriform cortex)

Olfactory tubercle

Lateral migratory stream (extends to olfactory tubercle)


Pr im


gon (ve al ba r ti c n d al l of B im ro b) ca

D ia

n no

y ar

Temporal lobe

ia i

m

u

(piriform ex )

a nt


Parolfactory gyrus

(infiltrates claustrum and penetrates insular cortex)

acc


b st

PREOPTIC AREA



N u cle u s

ar gyr u s


re issu mm o c r erio Ant

Ventral striatum Su



Globus pallidus

Uncinate fasciculus


Callosal sling

BASAL GANGLIA



SEPTUM

Putamen

al c a p s u Clau le strum

I n s ul

Lateral fissure


us callosum (body)

Abnormal hemorrhage in the germinal matrix

In


tri

cle


Induseum griseum

C o rp

en

b) im d) rl ea rio (h te us an cle e( nu ul ps ate ca ud al rn te

Frontal lobe

Cingulate gyrus




256



257

PLATE 176B Germinal and transitional structures in italics Interhemispheric fissure


Cingulate gyrus

Induseum griseum

ng Ci

um ul

Frontal lobe

b) d) ea im (h rl us rio cle te nu an e( ate ul ud ps Ca ca al rn te In

La ter al v ent ric le

Fornical

SEPTUM glioepithelium

Cave of the septum

External ca psu


le Be of d nu ter the s cleu mi tri s na a lis

Medial preoptic nucleus? min i n n oDiagonal band of Broca (horizontal limb)

yo

lf

tor


y co

rtex

Third ventricle (pir (preoptic recess) ifo r

) m

Fusiform gyrus

Magnocellular preoptic nucleus (part of the horizontal limb of diagonal band)

Parolfactory/ parahippocampal gyrus

Glial migration? (into optic chiasm)


tubercle

P ri

m

or y cortex (p lfact o y ar

(infiltrates endopiriform nucleus and penetrates piriform cortex)

iriform)

Lateral olfactory tract Sexually dimorphic nucleus?

Anterior amygdaloid area?

Layer I

(extends to olfactory tubercle) Preoptic glioepithelium/ ependyma Lateral preoptic Medial area preoptic Olfactory area

PREOPTIC AREA

i m ar






tia Substan


Anterior commissure

ata

Anterior commissure

Islands of Calleja?


White matter

Fornix


ac

Cortical plate


BASAL GANGLIA

Pr



Stria terminalis

Ventral striatum Uncinate fasciculus


Fornix (column)

Choroid plexus

ustrum

ar gy r u s


Anterolateral striatal neuroepithelium and subventricular zone Callosal sling

Putamen

Cla

I n s ul

Lateral fissure






Optic chiasm Subpial granular layer


Temporal lobe

(extends to temporal cortex)

258



259



ul Cave of the septum

Fornix

G (in lob ter us na pa l s llid eg u me s nt )

ina

G (ex lobus ter nal palli seg dus me nt) ullary la Med m Lateral nucleus

Fusiform gyrus

Mo nro Fo r

(infiltrates claustrum and penetrates insular cortex) Thalamic glioepithelium/ ependyma

s

Third ventricle

Supraoptic nucleus

Lateral hypothalamic area Hypothalamic glioepithelium/ ependyma



(extends to temporal neocortex)

HYPOTHALAMUS

Arcuate nucleus

Basal nucleus

Layer I

White matter


Stria medullaris

ri

ei

ucl

al n

AMYGDALA



Fornix

ct tra tic Op

Nuc. of the lateral olfactory tract?

rtic Co

Central nucleus


am

cl


Medial nucleus

Choroid plexus stem cells?

Choroid plexus

ParaSubsta la ventricular ntia u nucleus ti c Anterior in le n nom commissure Ansa inata n rai reb o f e l l dia nd Basal nuc. Intercalated masses Me bu of Meynert

Temporal lobe

Cortical plate


Subfornical organ

nu


Callosal sling

inalis erm ia t str he ft so eu


Uncinate fasciculus

um

le

ustrum

Ventral striatum



le

Stria terminalis B ed

Cla

ar gy r u s


t ric

BASAL GANGLIA Putamen

I n s ul

Lateral fissure

ve n


In External ca psu


al

b) d) im ea rl (h rio us te cle an nu e( ul ate ps ud ca Ca al rn te

Frontal lobe

er

of

ng

L

at


Induseum griseum

en

Ci

Cingulate gyrus



Migratory waves

(from the lateral migratory stream accumulate in the lateral nucleus)


Subpial granular layer Parahippocampal stratified transitional field (intermingled with the amygdaloid glioepithelium/ependyma)

260



261

PLATE 178B Germinal and transitional structures in italics Cave of the septum Lateral ventricle

a

G (in lob ter us na pa l s llid eg u me s nt )

s a ri

ul

ata

Intercalated masses

i

cle

Inferior temporal gyrus Lateral nucleus Layer I Cortical plate White matter

l nu

Temporal lobe

a rtic

Co

Basal nucleus

Fusiform gyrus



tic

tra

ct


edial Ventrom s nucleu

Op

ic

Fornix

in

Medial nucleus

nt

l edia som Dor ucleus n

om

A nsa le

L RA EX T L N P VE OM C BE LT

e

G (ex lobus ter nal palli Medu ll a seg dus ry me lam nt) in

cl


ANTERIOR COMPLEX

RE

T


BASAL GANGLIA


Mammiliothalamic tract?



Hypothalamic glioepithelium/ ependyma Lateral hypothalamic area

HYPOTHALAMUS

AMYGDALA Amygdaloid glioepithelium/ependyma

Arcuate nucleus

Parahippocampal neuroepithelium and subventricular zone Parahippocampal stratified transitional field Subpial granular layer Entorhinal cortex


R

nu

a in n

Stria medullaris

LA

ar

anti

Subfornical organ

ial ed om s ter leu An nuc

ul

Subst

Central nucleus

F of oram M en on ro

THALAMUS

Basal nuc. of Meynert

Anterior commissure

Fornix

ular nuclei Periventric

tic Re b) lim d) ior ea (h ter an us e( sul cap

e



us



Fornical Fornix glioepithelium glioepithelium?

U

c le al ern Int

sul

ustrum

Ventral striatum Uncinate fasciculus


Putamen

Cla

ar gy r u s


I n s ul

Lateral fissure

Stria terminalis

Choroid plexus

IC

nu


PERIVENT RICU COMPLEX LAR

ate


Third ventricle

ud

Extern al ca p


Callosal sling


Ca

Frontal lobe

Induseum griseum


Migratory waves

(from the lateral migratory stream accumulate in the lateral nucleus)


262



263

PLATE 179B Germinal and transitional structures in italics Cingulum

Lateral ventricle

Central sulcus

Frontal lobe

Cingulate gyrus

Precentral gyrus

Frontal/paracentral neuroepithelium and subventricular zone Frontal/paracentral stratified transitional field



Induseum griseum


A comnterior miss ure

act

ic a

cl l nu ei

A CONTE M RI PL OR EX



Hippocampus


V CO EN M TRA PL L LA EX R BE LT


TI

CU


RE

RA NT CE

G (ex lobus ter Medu nal palli ll a seg dus ry me lam nt) G in (in lob a ter us na pa l s llid eg u me s nt ) Basal nucleus

THALAMUS PL L COM EX

nt

ra

Cerebral peduncle

ort


Reuniens nucleus?

BASAL GANGLIA

Third ventricle

Lateral migratory stream ial omed edial x Dors m entro um? rni and v r continu a Fo nucle

C

s

Third ventricle

Massa intermedia

Forel's fields

Optic tr

Central nucleus Intercalated masses

eu

ular nuclei Periventric

is ?

cl

ro on

c u la r

nu



fM


ral nucleus?

e n ti

Lateral ventricle Fusiform gyrus

e nt Parac

sa l

r

a

An

Lateral nucleus

Layer I

e

ul

Ventral striatum


ia m

ic

Putamen

ull ar is

oter An edial m leus nuc

act ic tr lam tha lo-

e

Temporal lobe


sul


mi am M

cap

Uncinate fasciculus?

ustrum


Cla

ar gy r u s

Lateral fissure

I n s ul

Parietal lobe

Stria terminalis

(extends to paracentral cortex)

Subfornical organ

Fo Fornix ra m en Anteroo ventral nucleus d S tr

e

t ) Re mb r li erio ost a l/ p n tr (ce ule ap s al c ern Int

ac

Extern al

Par



PERIVENT RICU COMPLEX LAR

Caudate (tail)

l lo bu le

Postcentral gyrus

Abnormal Cave of the hemorrhage in the septum germinal matrix Choroid plexus



Hypothalamic glioepithelium/ ependyma

HYPOTHALAMUS Tanycyte ependyma

Arcuate nucleus


Parahippocampal neuroepithelium and subventricular zone Parahippocampal stratified transitional field Entorhinal Subpial granular layer cortex

AMYGDALA Amygdaloid glioepithelium/ependyma Lateral migratory stream (extends to amygdala)


264



265

PLATE 180B Germinal and transitional structures in italics Lateral ventricle

Central sulcus


Postcentral gyrus

Induseum griseum Abnormal hemorrhage in the germinal matrix

Reuniens nucleus?

Cerebral peduncle

Stria terminalis? Intercalated masses

Subiculum

BEL T

AR UL

SUBTHALAMUS

Supramammillary area

Lateral mammillary nucleus

Entorhinal cortex



AM


Hippocampus (Ammon's horn)

Hypothalamic glioepithelium/ ependyma

Fornix and mammillothalamic tract

act

Central nucleus?

BASAL GANGLIA


Third ventricle

Forel's fields

Ansa lenticularis? O ptic t r

A CONTE M RI PL OR EX


Zona in certa

Subthalamic nucleus

EX

PERIVENTRICULAR COMPLEX

TI C

s


RE

le u


V CO EN M TRA PL L EX

ln

uc

PL

DORSAL COMPLEX

Massa intermedia



NTR AL CO M

ra

G (ext lobus p erna allid l seg us Medullar men y la t) min Glo a (int bus ern pal al s lidu egm s ent )

Third ventricle

nt

Ve s tr i n t r a l a tu m

Subfornical organ?

ace

comAnte mi rior ssu re

Pa r


ar is

Dorsomedial nucleus

s

Lateral ventricle

ull

eu

Caudate (tail)

cl


ed


nu

Temporal lobe


ar


THALAMUS

m

no

CE

e

um

Putamen


r ia

ro on

sul

ustr

ar gy r u s

Cla

I n s ul

Lateral fissure


St

fM

l ca p

Cortical plate

Fo ra me


(extends to paracentral cortex)

Anteromedial/posterior striatal neuroepithelium and subventricular zone

Fornix

Stria terminalis



Choroid Cave of the plexus septum

cul ) R e t i r limb rio oste ral/p cent ule ( caps rnal Inte

Extern a

White matter



ate ud Ca (tail)

Paracentral lobule

Layer I

Paracentral neuroepithelium and subventricular zone Paracentral stratified transitional field



YG

HYPOTHALAMUS

Medial mammillary nucleus


DA LA

Posterior striatal neuroepithelium and subventricular zone Temporal stratified transitional field


266



267

PLATE 181B


(dorsal complex)

ris lla

us

Globus pallidus Ventral posteromedial nucleus


Zon

Optic tract Stria terminalis Caudate tail


cer

rh

Subgranular zone Alvear glioepithelium

rtex

RA


Temporal lobe

i

n

Ento




co


al


HIPPOCAMPUS

le nc du pe

rn ho

u

BASAL GANGLIA

MIDBRAIN TEGMENTUM Substantia nigra

Pa rs Pars re compacta tic ul at a

m ulu bic esu Pr

n's Fusiform gyrus

b ic


al br re

mo

White matter

Su

RA

ta

Ce

Am

Dentate gyrus


ic am hal eus t b l Su nuc

Habenulo- interpeduncular tract

Red nucleus

lu m

CE Thalamic glioepithelium/ ependyma

Oculomotor complex (III)

a in

Fimbria

Lateral ventricle

NT


L

s

Third ventricle

NT

CO

eu


LC

MP LE X

DORSAL COMPLEX

u cl

Putamen

THALAMUS

r al n

e Reticular nucl


Dorsomedial nucleus

P a r a c e nt


External capsule

du ro me on Stria

Claustrum

Paracentral neuroepithelium and subventricular zone Posterior striatal neuroepithelium and subventricular zone

ANTERIOR COMPLEX (anteroventral nucleus)


fM

Ventral anterior nucleus?

Fo Fornix ra me no



septum

Stria terminalis

Layer I


VE

Caudate (tail)


LAR BELT

Choroid plexus Cave of the


Induseum griseum

R E TI CU


Lateral ventricle

Cortical plate


Cingulate gyrus

O M PLEX

Cingulum

PONS



Pontine gray Middle cerebellar peduncle Extramural migratory stream (from the precerebellar neuroepithelium to the pontine gray and the reticular tegmental nucleus)

268



269

PLATE 182B

cle u

s

M lem edial nisc us?

P

Pars compacta

rtex

co


Parabrachial Internucleus peduncular nucleus


i

n

Layer I

Ento

rh

Reticular tegmental nucleus Pontocerebellar fibers (decussation) Pontine gray Transpontine corticofugal tract Middle cerebellar peduncle

NTR

VE

T B E L

R E T I C U L A R

AL C O M PLEX

LC

RA

NT

CE

MIDBRAIN TEGMENTUM

al

Fusiform gyrus

le nc du pe ral reb


Ce

m ulu bic esu Pr

's h orn


a lat

Subiculum

Red nucleus



Strionuclear glioepithelium External capsule

Lateral migratory stream BASAL GANGLIA

PO STE RIO RC OM PLE X




THALAMUS

Su bs nig tanti ra a

e lat icu gen us pra cle Su nu

A

on


Paracentral/parietal stratified transitional field

X


s reticu ar

m

Third ventricle

PERIVENTRICULAR COMPL

u lar n Parafascicu


Fimbria

EX




m

la r nu b e le i H a nu c

Dorsomedial nucleus

ro on f M llaris u ed m

a

r al n u c l e u s


Dentate gyrus


a cent

n u c l e u s


Fo ra S t me ri n o


Pa r

R e t i c u l ar


Optic tract

Fornix


Putamen

Cave of the septum


OM PLE X



Corpus callosum

Choroid plexus

DOR SAL CO MP LE

Lateral ventricle

PONS


Stria terminalis Posterior striatal neuroepithelium and subventricular zone Caudate (tail) Lateral ventricle Subgranular zone Temporal neuroepithelium and subventricular zone

HIPPOCAMPUS

Temporal lobe

Alvear glioepithelium Parahippocampal neuroepithelium and subventricular zone Parahippocampal stratified transitional field

270



271

PLATE 183B Fornix

LC RA

NT

L T B E

R E T I C U L A R

O MPLEX

MPLEX

VE

Pr e te c tu m

r al n u c l e u s

Thalamic glioepithelium/ ependyma Centromedian nucleus

A L CO

a cent

External capsule Putamen

Stria terminalis

Subiculum


Reticular formation

MIDBRAIN TEGMENTUM

cu


s t ic

ula

r te

g m e ntal

le nuc

u

Pontocerebellar fibers (decussation) Pontine gray Pontocerebellar fibers (thin transverse bundles) Transpontine corticofugal tract (thick longitudinal bundles) Middle cerebellar peduncle

Posterior striatal neuroepithelium and subventricular zone Subgranular zone Alvear glioepithelium Dentate molecular layer Dentate granular layer Dentate hilus Stratum oriens Stratum pyramidale Stratum radiatum Stratum lacunosum moleculare

Lateral ventricle

n is Re

CA1

CA3

Caudate (tail)

Temporal neuroepithelium, subventricular zone, and stratified transitional field

s

co al

le m

n

ia l

i

ed

h

Reticular formation

Superior cerebellar peduncle (decussation)

M

r Ento


ncle pedu b ral Cere

Fusiform gyrus



rtex

m ulu bic esu Pr

White matter

POSTERIO R COMPLE X


Central gray

HI PP OC AM PU S

Reticular formation



Layer I

THALAMUS

Paracentral/parietal stratified transitional field Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Insular gyrus

Cerebral aqueduct

Ammon's horn

Cortical plate

Choroid plexus



Optic tract Fimbria Dentate gyrus

Pa r


Dorsomedial nucleus


Pulvinar


X

N TR

i et

u Ventral posterolateral nucleus

n u c le us


DOR SAL CO MP LE

R


c l a r

Putamen



CE


PONS


Temporal lobe Parahippocampal neuroepithelium and subventricular zone Parahippocampal stratified transitional field

272



273

PLATE 184B

em al l

s M

Middle cerebellar peduncle Pontocerebellar fibers (decussation) Pontine gray


al

e

di

le m


niscu


Transpontine corticofugal tract (thick longitudinal bundles) Middle cerebellar peduncle

LT B E

IO

Putamen

E



CA1

MIDBRAIN TEGMENTUM

CA3

Dentate molecular layer Dentate granular layer Dentate hilus

Alvear glioepithelium Subgranular zone Stratum oriens Stratum pyramidale Stratum radiatum Stratum lacunosum moleculare

Temporal neuroepithelium, subventricular zone, and stratified transitional field Lateral ventricle

nis c u Re us t ic u cle lar t e gmen t a l n u


Temporal lobe


PONS


Pontocerebellar fibers (thin transverse bundles) Nerve V

External capsule

R PO

ST

HIP PO CA MP US

Later

Trochlear nucleus (IV)

Stria terminalis

R R E T I C U L A

OM

Reticular formation


Layer I

LC

t


White matter Fusiform gyrus



Cerebral aqueduct


CE N T

Caudate (tail)

s

m ulu bic esu Pr

Subiculum

ior commi er ssu re Pretectum Po s Subcommissural organ Brachium of the inferior colliculus Central gray

Nucleus of the posterior commissure

RA

VENTRAL COMPLEX? (ventral posterolateral nucleus)

Ammon's horn

Cortical plate

Pulvinar

R COMPLEX

DORSAL COMPLEX (dorsomedial nucleus)

Pulvinar

Fimbria Dentate gyrus

P L E X (paracentral nu

THALAMUS

s n u c l e u


) cleus

R


et i c ul ar

Putamen



Nerve V

274



275

PLATE 185B T L

Optic nerve layer Superficial gray layer Middle gray layer Deep gray layer

Presubiculum

Deep white layer


TECTUM Superior colliculus

Ammon's horn

Layer I


Fusiform gyrus

Cerebral aqueduct

Cortical plate

MIDBRAIN

Central gray




Subgranular zone Stratum oriens Stratum pyramidale Stratum radiatum Stratum lacunosum moleculare

TEGMENTUM Temporal neuroepithelium, subventricular zone, and stratified transitional field

r Pa ab

TE R (H IO I- R H L V O ) B

N A


Nucleus of the lateral lemniscus (ventral)

Parahippocampal neuroepithelium and subventricular zone Parahippocampal stratified transitional field Nerve V (myelination gliosis)

Trapezoid body

Spinocephalic tract? Inferior olive complex

Temporal lobe


UM ) LL RE BE HE RE ISP CE EM (H


mniscus al le

d

Nerve VIII and ventral cochlear nucleus

edi

pe


cle

Raphe migration

M

ochlear nucleus?

d d l e c e re b ell a r

un

r cula Reti ation form

lc rsa Do

Mi



Reticular formation

PONS

(co Pyra rti mi c d tra ospin ct) al

E


s nucleu hial ebellar pedu cer ncl e

Abducens nucleus (VI)?

rac

r rio pe Su



Lateral ventricle

Dorsal tegmental nucleus?

Nucleus of the lateral lemniscus (ventral) Lateral lemniscus

Putamen


CA3

CA1

Reticular formation

Lateral lemniscus



HIPPO CAMP US

Subiculum

Dentate gyrus

White matter

POSTERIOR COMPLEX

Middle whitelayer

Fimbria

Stria terminalis

B

Pulvinar

cle u s


THALAMUS

Germinal and transitional structures in italics A R U L C I R E T

r nu

Stria terminalis

Zonal layer

E

t

i cu la

Strionuclear glioepithelium Posterior striatal neuroepithelium and subventricular zone

Re

Caudate (tail)

MEDULLA Arcuate nucleus (medulla)

276



277

PLATE 186B Superficial gray layer Middle gray layer


AR BELT

Deep white layer


MIDBRAIN

Layer I Brachium of the inferior colliculus


Central nucleus


Central gray

Cerebral aqueduct

HIPPO CAMP US

TECTUM Superior colliculus

POSTERIOR COMPLEX (Pulvinar)

ia br Fim

Deep gray layer

Cortical plate


THALAMUS

Middle white layer

White matter


Fimbria (R e

us) ucle rn ula tic

RET ICU L

Optic nerve layer?

Subiculum

Dentate gyrus


CA3

CA1

Lateral ventricle Temporal neuroepithelium and subventricular zone

Nerve IV root? P

Reticular formation

Inferior olive complex (principal nucleus)

al gray

complex

Medial lemniscus


ear Raphe nucl

ucleus? ear n

Raphe migration

Choroid plexus

Reticular formation

Temporal lobe

Locus coeruleus

CEREBELLUM


C e n tr

Latera l lemni scus e r ior cerebella r pedunc le

S up o c hl



u

s al c

Ventral cochlear nucleus

Spinal nucleus (V)


ISTHMUS

Motor nucleus (V)

Dor


Fourth ventricle


A


s

LO R ) O V RI I-H E H NT (


eu

BE


Isthmal and pontine glioepithelium/ependyma

al chi n c l

External germinal layer Molecular layer Purkinje cell layer Granule cell layer Medullary layer

HEMISPHERE


PONS

Motor nucleus (VII)

Part of section torn away

MEDULLA

(co Pyr rti am c tra osp id ct) ina l

Subgranular zone Stratum oriens Stratum pyramidale Stratum radiatum Stratum lacunosum moleculare

Inferior colliculus

arabra

Caudate (tail) Stria terminalis Posterior striatal neuroepithelium and subventricular zone

Spinocephalic tract?

Arcuate nucleus (medulla, penetrated by raphe migration)


278



279



MIDBRAIN TECTUM

Central nucleus

(Inferior colliculus)

VERMIS

CEREBELLUM

Centralis (III)


AN



BE



(I, II)


Superior vestibular nucleus Inferior vestibular nucleus

Medial vestibular nucleus


Prepositus nucleus


Reticular formation


Nucleus ambiguus?

Inferior olive complex (principal nucleus)

Medial lemniscus


d l mi a ra spin y P tico t) r ac (co tr

HEMISPHERE

Pontine and medullary glioepithelium/ ependyma

Fourth ventricle

mplex r co


PONS

lea e nuc

Choroid plexus


Cerebellar dentate nucleus


Flocculus (HX) Germinal trigone (continuous with stem cells of the choroid plexus)


Lingula

Raph

Ansiform lobule Crus II Paramedian lobule (HVIIA) (HVIIB)

chlear Ventral coeus nucl


LO R ) O V RI I-H E T (H

Vestibular nuclear complex Part of section torn away

Reticular formation


MEDULLA Spinocephalic tract?

280



281

PLATE 188B External germinal layer Molecular layer Purkinje cell layer Granule cell layer Medullary layer


Culmen (IV, V)

CEREBELLUM

VERMIS Centralis (III)

ANTERIOR LOBE (HI-HV)


Lingula (I, II)


Interpositus nucleus Superior cerebellar peduncle

RE

BE

L

L

A

CL

EI


Germinal trigone

Choroid plexus Medial vestibular nucleus

Fourth ventricle

nu Sol cl ita traeus ry ct and Cuneate nucleus





MEDULLA


Dorsal sensory nucleus (X) Dorsal motor nucleus (X)


Spinal nucleus and tract Nucleus of Roller (V) Lateral reticular nucleus

Inferior olive complex (principal nucleus) Medial accessory olive

scus al lemni Medi



lex Raphe nuclear comp

Choroid plexus

NU

Germinal trigone

(X)

EP

Flocculus Paramedian (HX) lobule (HVIIB)

E


HEMISPHERE

D

Nodulus

Dentate nucleus Middle and inferior cerebellar peduncles


CE

R


Fastigial nucleus

id Pyramspinal o c i t r (co ract) t

Medullary glioepithelium/ependyma Reticular formation Medial longitudinal fasciculus and tectospinal tract

MEDULLA


Spinocephalic tract?

282



283


VERMIS



Culmen (IV-V) ANTERIOR LOBE? (HI-HV)


Fastigial nucleus

Centralis (III)

Inte rp nuc ositus leus

CE

Nodulus (X)

BE

L

L

HEMISPHERE

A

D E

Dentate nucleus

RE

R


CEREBELLUM

EP

EI


Germinal trigone

CL

(X)

Floccular peduncle

NU

Uvula? Nodulus (IX)

Choroid plexus Biventral lobule Gracile (HVIII) fasciculus Paramedian lobule Cuneate (HVIIB) fasciculus

Fourth ventricle

Area postrema

Cuneate nucleus


Spinocerebellar tracts Accessory nucleus (XI) Spinocephalic tract? Pyramidal decussation Pyramid (corticospinal tract)


Choroid plexus


Reticular formation


Commissural nucleus (X) Central canal (medulla/spinal cord) Spinomedullary glioepithelium/ependyma

MEDULLA

Raphe nuclear complex Medial longitudinal fasciculus and tectospinal tract

284

PART PARTVIII: VIII:


This specimen is case number W-147-63 (Perinatal RPSL) in the Yakovlev Collection. A female infant survived for 27 days after a premature birth. Death occurred from a hemorrhage in the abdominal cavity. The brain was cut in the sagittal plane in 35-µm thick sections and is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). Since there is no photograph of this brain before it was embedded and cut, the photograph of the medial view of a GW25 brain that Larroche published in 1966 (Figure 6) is used to show gross anatomical features. Photographs of 10 different Nissl-stained sections (Levels 1-10) are shown at low magnification in Plates 190-199. The core of the brain and the cerebellum are shown at high magnification in companion Plates 200AB-209AB for Levels 1-6. Very high magnification views of different regions of the cerebellar cortex are shown in Plates 210-215. Because the section numbers decrease from Level 1 (most medial) to Level 10 (most lateral), they are from the left side of the brain; the right side has higher section numbers proceeding medial to lateral. The cutting plane of this brain is nearly parallel to the midline in anterior and posterior parts of each section, including different parts of the cortex. The sections chosen for illustration are spaced closer together near the midline to show small structures in the diencephalon, midbrain, pons, and medulla.

Y15-60 contains the same group of immature structures as in the older specimens, except that all of these structures are more prominent. In the telencephalon, thicker remnants of the germinal matrices are present in all lobes of the cerebral cortex where the neuroepithelium/subventricular zone are generating neocortical interneurons. Migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields, thin in the occipital lobe, and thicker in the frontal, parietal and temporal lobes. More neurons, glia, and their mitotic precursor cells are migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Streams of neurons and glia percolate through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus in the lateral migratory stream. These cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a thick neuroepithelium/ subventricular zone overlying the striatum and nucleus accumbens where neurons and glia are being generated; some of these, especially from the accumbal area, will enter the rostral migratory stream. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the

source of granule cells. Just as in the GW37 specimens, the septum, fornix, and Ammon’s horn have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle. Most of the structures in the diencephalon appear to be settled and are maturing, but the glioepithelium/ependyma lining the third ventricle is more thick than in the older specimens. A convoluted glioepithelium/ependyma lines the cerebral aqueduct in the midbrain. A smooth glioepithelium/ependyma lines the fourth ventricle through much of the pons. Another convoluted glioepithelium/ ependyma lines the fourth ventricle through much of the medulla, part of that may be a remnant of the germinal source of the precerebellar nuclei. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is actively producing basket, stellate, and granule cells. The germinal trigone is visible at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia are originating here and some migrating neurons may still be in the trigone.

285

(Precuneus)

gu Cin

)

LOB E

su us

BE

RAL

(Lingula)

ulc

CIPITAL LO OC

TEM

PO

ooc cip ita

m

(Gyrus rectus)

iet

iu

Hypothalamus

(Cuneus)

Calca rin es

DIENCEPHALON

m ctu Te N AI BR ID um M ent gm Te

Subcallosal area

l

Pa r

le n

Thalamus

tum

Genu

l cu s

(R etr os

enial area pl

sum s callo u p r Co Fornix

Sp

( Su pe rio r

us sulc e t a l ngu gyrus Ci l a te

BE LO

on fr

ta

) rus y lg

PAR IE TA L

Marginal sulcus

Sep

NTAL LOB E) (FRO

CENTRAL LOBULE) A R A P (

Cerebellar vermis

PONS

M

ED

UL L


A

Spinal cord

Figure 11. Midline sagittal view of a GW25 brain with major structures in the cerebral hemispheres and brainstem labeled. (This is part of Figure 2-9 on page 27 in B. A. Curtis, S. Jacobson, and E. M. Marcus (1972) An Introduction to the Neurosciences, Philadelphia: W. B. Saunders. The photograph was originally published by J. C. Larroche (1966) The development of the central nervous system during intrauterine life. In: Human Development, F. Falkner (ed.), Philadelphia: W. B. Saunders, page 259.)

286



6 7 8 9 10 11

Rostral migratory stream Diencephalic glioepithelium/ependyma Diencephalic/mesencephalic glioepithelium/ependyma Mesencephalic glioepithelium/ependyma Pontine glioepithelium/ependyma

Precerebellar glioepithelium Medullary glioepithelium/ependyma Raphe migration Germinal trigone (cerebellum) External germinal layer (cerebellum) Subpial granular layer (cortical)


Frontal lobe

11

Hippocampal commissure?

Fo rn ix

Ca v se p e o f tu m th e

m llosu

11 Frontal lobe

Subcallosal area

Third ventricle

um pt Se

Genu

1

1

2

Layer I

ple xu s

3

11

Pineal gland Posterior commissure

Occipital lobe

Superior Interpeduncular colliculus nucleus Tectum

Midbrain

Hypo- Tegmentum thalamus

Olfactory bulb and peduncle Optic chiasm Oculomotor nerve(III) Cerebral peduncle Transpontine corticospinal tract Basal pontine gray


Ch or oid

Anterior commissure

Preoptic area

Gyrus rectus

White matter

ium len Sp

ca us rp o C

Cortical plate

Parietal lobe

Inferior colliculus

4

Fourth ventricle

Pons

Anterior lobe

5 9


Nerve IV root?

10

Central lobe

Inferior lobe Posterior lobe

6

8

Inferior olive complex Pyramid (corticospinal tract) Pyramidal decussation

7 Medulla

Primary fissure

Cerebellum (vermis)


10

Medial longitudinal fasciculus and tectospinal tract Gracile faciculus and nucleus Spinal cord

287

PLATE 191 Remnants of the germinal matrix, migratory streams, and transitional fields 7 Mesencephalic glioepithelium/ependyma 1 Rostral migratory stream 8 Pontine and medullary glioepithelium/ependyma 2 Callosal sling 9 Raphe migration 3 Callosal glioepithelium 10 Spinal glioepithelium/ependyma 4 Fornical glioepithelium 11 Germinal trigone (cerebellum) Strionuclear glioepithelium 5 12 External germinal layer (cerebellum) Diencephalic (thalamic) glioepithelium/ependyma 6 13 Subpial granular layer (cortical)


See detail of brain core and cerebellum in Plates 201A and B. Paracentral lobule

Cingulate gyrus

Frontal lobe

Anterior commissure

Gyrus rectus

1

ple xu s

Ch or oid

2

Fo rn ix

C Genu

4

um pt Se

13

sum a l lo

5


Third ventricle

6

Preoptic area

13

Pretectum

Thalamus Fornix

White matter

ium len Sp

Cave of the septum

3

sc pu or

Layer I

3

Induseum griseum

Frontal lobe

Cortical plate

Parietal lobe

13

Superior colliculus Interpeduncular nucleus Tectum

Midbrain

Hypothalamus Tegmentum


Inferior colliculus

Anterior lobe

7

Occipital lobe

12

Primary fissure

Olfactory peduncle Fourth Inferior Cerebellum lobe ventricle Optic chiasm (vermis) Central Oculomotor nerve(III) Pons lobe Cerebral peduncle Posterior lobe Transpontine corticospinal tract Pontine gray Medulla Medial lemniscus Medial longitudinal fasciculus and tectospinal tract Pyramid (corticospinal tract) Raphe nuclear complex (infiltrated by ) Gracile fasciculus and nucleus Pyramidal decussation

11

8

12

9


Central canal (spinal cord, surrounded by

10)

Spinal cord

See high magnification views of the cerebellar cortex and germinal trigone in Plates 210-215.

288



6 7 8 9 10

Rostral migratory stream Callosal glioepithelium Fornical glioepithelium Strionuclear glioepithelium Diencephalic (thalamic) glioepithelium/ependyma

Mesencephalic glioepithelium/ependyma Pontine and medullary glioepithelium/ependyma Germinal trigone (cerebellum) External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 202A and B. Paracentral lobule Parietal lobe

10

Septum

4

5

Preoptic area

Islands of Calleja and medial nucleus accumbens

1

10


Superior colliculus

Midbrain

Inferior colliculus

Anterior lobe

Pons 6

Oculomotor nerve(III) Transpontine corticofugal tract

Fourth ventricle

9 Primary fissure

8

7

Pontine gray Medial lemniscus Inferior olive complex

Occipital lobe

Tectum

Hypothalamus Tegmentum

Olfactory peduncle

Fasciola cinereum

Pretectum

Thalamus

Anterior commissure

Cingulate gyrus

Orbital gyrus

Third ventricle

Layer I ium len Sp

3

Genu

Frontal lobe

2

s yru te g a l u g losum Cin rpus cal o C

2

10

White matter

Induseum griseum

Fornix (precommissural) Fornix (postcommissural) Cave of the septum

Frontal lobe

Cortical plate

Inferior Central lobe Posterior lobe

lobe

Cerebellum (lateral vermis)

9

Paraflocculus (HIX)

Medulla


Gracile fasciculus and nucleus

Pyramidal decussation Spinal cord

289

PLATE 193 Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium

6 7 8 9 10

Accumbent neuroepithelium and subventricular zone (intermingled with the rostral migratory stream) Strionuclear neuroepithelium and subventricular zone Pontine glioepithelium/ependyma External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 203A and B. 10 Paracentral lobule

Cortical plate

Frontal lobe

Cingulate sulcus

7

3

accNucl um eus be ns

Genu

2

Orbital gyrus

10

1

Olfactory tubercle

5

For nix

DORSAL COMPLEX AN CO TE M RI PL O EX R . CENTRAL COMPLEX

Thalamus

Be

6

Stria medullaris

Hypothalamus

Subthalamus

ium len Sp

Cingulum

osum

R IO ER X ST PLE PO OM C

Lateral ventricle

Induseum griseum

4

Cingulate gyrus

s c a ll rpu o C

4

Frontal lobe

Layer I Parietooccipital sulcus

Cingulate gyrus (retrosplenial area) Calcarine fissure

Fasciola cinereum Hippocampal commissure


Superior colliculus

Tectum

Midbrain

Inferior colliculus

Hippocampus

Primary fissure

Anterior lobe

Entorhinal cortex

Fourth ventricle

Cerebral peduncle Pons Medial lemniscus Transpontine corticofugal tract Pontine gray Motor nucleus (VII) Medulla Vestibular nuclear complex Inferior olive complex Lateral reticular nucleus Lateral funiculus

Occipital lobe

Lateral lemniscus

Tegmentum

8


Parietal lobe

Marginal sulcus

White matter

ri f st a ter m


d nuc. o

1 2 3 4 5


Simplex lobule

Dentate nucleus

10

Ansiform lobule (crus I) Ansiform lobule (crus II)

Paraflocculus (HIX)

9



9


Cuneate fasciculus and nucleus Spinal nucleus and tract (V)

Spinal cord

290

PLATE 194 Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium Occipital stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field

8 9 10 11 12 13 14

Alvear glioepithelium Amygdaloid glioepithelium/ependyma Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)

Central sulcus Cortical plate

Paracentral lobule Frontal lobe

14

Induseum griseum?

Cin

Internal

Basal ganglia

Caudate

Globus PO pallidus Subthalamus Nucleu accumb s Substantia le ens innominata nc eb r a l p e du

Orbital gyrus

14


CENTRAL COMPLEX

c

r

2

For nix

Olfactory tubercle

9

7

Ventral hippocampus

8

al hin tor rtex n E co

Pons Lateral ventricle Nerve V (root) Middle cerebellar peduncle Inferior cerebellar peduncle Spinocerebellar tracts?


Cingulate sulcus

te g

yru

14

s

s ru a) gy re te ial a a l u n ng le Ci rosp t (re

Thalamus

Ce

3

1

MPLEX CO

m

Pa ST ra hip ER po IO R LE ca CO MP mp al gy ru s

10

12

L R SA X D O PL E M CO

sule ap

Corona radiata

4

11

5

VENTRAL

Frontal lobe

4

sum a l lo

gula

g u lu

White matter

ium len Sp

c us rp o C

C in

Layer I

Parietal lobe

Marginal sulcus

Am yg da la

1 2 3 4 5 6 7




X


Dorsal hippocampus

13

r erio Antlobe

Primary visual cortex Calcarine sulcus

6

6

Primary fissure Simple lobule x

Dentate nucleus

Occipital lobe



Paramedian lobule Biventral lobule Paraflocculus

291



Central sulcus


lobule Paracentral

Frontal lobe

Globus pallidus

Olfactory tubercle Primary olfactory cortex (piriform)

Am yg da la

Nucleu inSub s no sta accum mi nti bens na a ta

16

11

Lateral ventricle Damaged areas in section

5

8

s

us ) yr rea e g al a t a i l n Dorsal ingusple hippo- C tro e campus (r Calcarine sulcus

Pa ra ST hi pp ER oc IO R LE am CO MP pa lg yr us

dat

C au

Basal ganglia

ps ul e

Thalamus CENTRAL COMPLEX

Subthalamus le nc eb r a l p e du

10

9


16

7 6

PO

16

al por Temlobe

Ventral hippocampus

al hin tor rtex n E co

Nerve V (root) Middle cerebellar peduncle Ventral cochlear nucleus? Dorsal cochlear nucleus Inferior cerebellar peduncle


gyru

For nix

MPLEX CO

r

Orbital gyrus

rn Inte al ca

VENTRAL

14

Ce

a ron Co diata ra

3

2 1

Choroid plexus SAL DOR LEX P COM

13

e


12

late

4

sum a l lo

ium len Sp

4

Parietal lobe

Cin gu

c us rp o C

Frontal lobe

White matter

X

1 2 3 4 5 6 7 8

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 9 Alvear glioepithelium Frontal neuroepithelium and subventricular zone 10 Subgranular zone (dentate) Frontal stratified transitional field 11 Amygdaloid glioepithelium/ependyma Callosal glioepithelium 12 Anterolateral striatal neuroepithelium and subventricular zone Fornical glioepithelium 13 Anteromedial striatal neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone 14 Strionuclear glioepithelium Occipital stratified transitional field 15 External germinal layer (cerebellum) Parahippocampal neuroepithelium, subventricular 16 Subpial granular layer (cortical) zone, and stratified transitional field

15

r erio Antlobe

Occipital lobe

Primary fissure Simple lobule x

Dentate nucleus


15


Paramedian lobule Biventral lobule Paraflocculus Flocculus

292


1 2 3 4 5 6 7 8 9

Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream (source area) 10 Alvear glioepithelium Frontal neuroepithelium and subventricular zone 11 Subgranular zone (dentate) Frontal stratified transitional field 12 Lateral migratory stream (cortical) Callosal glioepithelium 13 Amygdaloid glioepithelium/ependyma Fornical glioepithelium 14 Anterolateral striatal neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone 15 Anteromedial striatal neuroepithelium and subventricular zone Occipital stratified transitional field 16 Strionuclear glioepithelium Temporal neuroepithelium and subventricular zone 17 External germinal layer (cerebellum) Parahippocampal/temporal stratified transitional field 18 Subpial granular layer (cortical)

See detail of brain core and cerebellum in Plates 206A and B. Central sulcus

Postcentral gyrus

Precentral gyrus

Cortical plate

lobule Paracentral

Frontal lobe Cin gul

Corona radiata

18

12

Orbital gyrus

PO

S innuobstant min ia ata

Cerebral peduncle

11 10 8

5

10

Thalamus

Globus pallidus

13

For nix

l ra po e m Te lob

gyr

us

(r Cin et g ro ul sp at len e g ia yr l a us re a)

MPLEX CO

4

Pa ra hi ST pp ER oc am IO R LE CO MP pa lg yr us

Nucleu s accum bens

VENTRAL

Ca ud at e

Basal ganglia



Internal

Am yg da la


3

14

le su

2 1

Corona radiata

Choroid plexus

15

p ca

4

16

X

Frontal lobe

4


ium len Sp

c us rp o C

ate

sum a llo

Layer I White matter

Parietal lobe


Dorsal Calcarine sulcus hippocampus

Ventral hippocampus

9

io te r A n lo b e

18 Lateral ventricle Middle cerebellar peduncle Dentate nucleus Inferior cerebellar peduncle

Primary fissure

r

Simplex lobule

18

6

Lateral ventricle

Occipital lobe

7 Ansiform lobule (crus I)

Ansiform lobule (crus II)

17


Paramedian lobule Biventral lobule Paraflocculus? Flocculus

293




Central sulcus

Postcentral gyrus

Precentral gyrus


lobule Paracentral

5

Corona radiata Lateral ventricle

17 18

16

ap lc na

1

Corona radiata

e sul

2

Inter

Basal ganglia Putamen

14 Orbital gyrus

Primary olfactory cortex (piriform) Lateral ventricle


MPLEX CO

7 EX

Frontal lobe

3

Cor pus c 6 allosum

4

2

Globus pallidus

Choroid plexus

Fornix

Thalamus


Cerebral peduncle

12

PO

13


13

Dorsal hippocampus

6 (r Cin et g ro ul sp at len e g ia yr l a us re a)

3

White matter

Parietal lobe

C O M PL



OR



RI



Calcarine sulcus

TE



al or p m e Te lob

15 10 11


l ra te icle La ntr ve

8

S

hip Ven po tra ca l mp us



VENTRAL



la



da



yg


11 12 13 14 15 16 17 18 19 20

Am


Ca ud at e

1 2 3 4 5 6 7 8 9 10


io te r A n lo b e

r

20 Occipital lobe

9

Primary fissure Simplex lobule



19 Cerebellum (hemisphere)

Paramedian lobule

Inferior cerebellar peduncle Flocculus

Biventral lobule

294



9 10 11 12 13 14 15 16

Frontal stratified transitional field Paracentral stratified transitional field Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Occipital neuroepithelium and subventricular zone Occipital stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

Alvear glioepithelium Subgranular zone (dentate) Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma Posterior striatal neuroepithelium and subventricular zone Strionuclear glioepithelium External germinal layer (cerebellum) Subpial granular layer (cortical)

See detail of brain core in Plates 208A and B. Postcentral gyrus

Central sulcus

Layer I

Precentral gyrus

15

ac e t n

ra

P

ar

nt



15

12

10 s

Choroid plexus

7

pp Hi

a la

11

Latera l ventric le

ygd Am

Claustrum

11

3

8

7

Lateral ventricle

16

5

6

Occipital lobe

oc

I

Orbital gyrus

16

Globus pallidus

POSTERIOR COMPLEX

Lateral ventricle

14

Thalamus

er

Basal ganglia

Corona radiata

(po ste rio rl i

Putamen


13

pu

r io

ul e

3

am

na er

n te

c a ps

n al capsule

t In

e (a

Caudate (tail)

b) m

1

a lc

l p su

Internal

b) r lim

White matter

4

2

Frontal lobe

Cortical plate

Parietal lobe

l lo

bu le

Corona radiata

9

Temporal lobe

8

Ansiform lobule (crus I) Ansiform lobule (crus II) Paramedian lobule

15


295




See detail of brain core in Plates 209A and B. Central sulcus

White matter

Parietal lobe

ul

e

Par

en

ac

Frontal lobe

ri gy

Cortical plate

Postcentral gyrus

Precentral gyrus

10

Layer I

t ra

l lo

b

2

10

Frontal lobe

Putamen

6 4

5

10

3

7

Fi mb ria

Basal ganglia

5

Insular gyrus

Internal capsule

um

C pl horo ex id us

a Cl

tr us

Lateral fissure



gy r

Corona radiata

u

Parietal lobe

Caudate

us

Ins

Orbital gyrus

10

Corona radiata

Am yg da la



l ar



ro nt al



rf


6 7 8 9 10

middle, and infe rio


erior, Sup

1 2 3 4 5

8

1

Lateral ventricle

3

Temporal lobe

4

Cerebellum Ansiform lobule (hemisphere) (crus I) Ansiform lobule (crus II)

9

296



297

2

2


4 Raphe nuclear complex Medial lemniscus

9

Pontine gray Raphe nuclear complex (infiltrated by the Raphe migration) Arcuate nucleus (medulla, penetrated by Raphe migration) Medial accessory olive


Prepositus nucleus

10

X

INFERIOR LOBE

E

6


Germinal trigone External germinal layer

11

E

CEREBELLUM B

A

C

Choroid plexus

D Uvula IX

POSTERIOR LOBE

11

Declive VI

V ER M I S

E Nodulus

N CE

D

Tuber VIIb

T

C

Pyramis VIII

11

Area postrema?

Medial longitudinal fasciculus and tectospinal tract Gracile nucleus Gracile fasciculus


SPINAL CORD


Lateral corticospinal tract (medial edge) Ventral funiculus (spinal cord)

Folium VIIa


MEDULLA




B


Medullary glioepithelium/ependyma Raphe migration

E

Culmen IV, V

Fastigial nucleus e ll a r ped u n cle

7

Medial lemniscus

Principal olivary nucleus

Precerebellar glioepithelium

5

Reticular formation

PONS


Med ia

cle


8

er eb

i ntr ve


Substantia nigra (pars reticulata) Ventral tegmental area and substantia nigra (pars compacta) Transpontine corticofugal tract (thick longitudinal bundles)


IOR LOB

A

rc rio pe

Diencephalic/mesencephalic glioepithelium/ependyma

Cerebral peduncle

Reticular formation

th ur Fo

Diencephalic glioepithelium/ependyma


D

Su


N

R TE

Centralis III Lingula I, II

us ngitudinal fascicul l lo

1 2 3 4 5 6 7 8 9 10 11 12


us nucle


Arcuate nucleus

al Dors nucleus l en ta tegm sciculus l fa in a

Olfactory bulb and peduncle

IDB BR M ID R A IN


t al men r teg ula tic Re

12

TEGMENTUM Mammillary body


Brachium of the inferior colliculus Nerve (IV) bundles?

Central nucleus

ud

1

Optic chiasm

Inferior colliculus


g it

White matter

Red nucleus

lo n

1


C

TECTUM


ial

Gyrus rectus


Superior colliculus

Central gray

ed M

12


3

THALAMUS massa intermedia (damaged)

HYPOTHALAMUS Dorsomedia ventromedia l and l nuclei

PREOPTIC AREA


Cortical plate

3

Forel's fields

Subcallosal area

Layer I

Cerebral aqueduct

Median preoptic nucleus Anterior commissure

se M pt e (d al dia am nu l ag cl ed eu ) s

Pineal gland


E

Third ventricle

B

LOB

SEPTUM


AL


Fornix

A

R

Callosal sling


A

Induseum griseum

Cave of the septum

Cerebellar fissures


Choroid plexus

Pr et ec tu m

Co rp u (b s ca od llo y) su m

PLATE 200B

Medial motor nucleus (spinal cord)

298


See the entire section in Plate 191 and high magnification views of the cerebellar cortex and germinal trigone in Plates 210-215.

299

PLATE 201B

Medial lemniscus

*Raphe nuclear complex

11


Cerebellar glioepithelium/ependyma Raphe migration

R LOB

A

E

Culmen IV, V

13

CEREBELLUM B

Fastigial nucleus

B


SPINAL CORD Ventral funiculus (spinal cord)

9

INFERIOR LOBE

E

Choroid plexus

Uvula IX

Declive VI

POSTERIOR LOBE

T Tuber VIIb N CE C

VIII

D

D

Dorsal motor nucleus (X) Dorsal sensory nucleus (X) Gracile fasciculus Gracile nucleus


Germinal trigone Damaged areas in section

RIO

Centralis III

er

MEDULLA




E

7

le


N

Lingula I, II

Reticular formation



Locus coeruleus


TE

ventric


E

Fourth

*Infiltrated by the Raphe migration



rc rio pe


Central nucleus

Su



D

8 10 ebellar peduncle Abcucens V ER M I S 12 nucleus (VI) C Dorsal Nodulus longitudinal E X fasciculus Pyramis

Pontine gray

Callosal glioepithelium Fornical glioepithelium

ci

Medial lemniscus

Rostral migratory stream Callosal sling?


LOB

PONS


C

Inferior colliculus


1 2 3 4 5 6 7 8 9 10 11 12 13 14

fa s

Reticular formation




Substantia nigra


TECTUM

s lu cu

TEGMENTUM

Oculomotor nerve (III) Pontocerebellar fibers (thin transverse bundles)

al

in

Optic chiasm

B

M I D BR A IN ud

14

1

Mammillary body

Optic nerve layer

it ng lo

1

Red nucleus


cle un ed lp ra reb Ce


Fornix

ed ia l

M

Dorsomedial nucleus

Central gray

Forel's fields

HYPOTHALAMUS


Olfactory peduncle


Superior colliculus


AL

PREOPTIC AREA

Supraoptic nucleus

Gyrus rectus

Habenulointerpeduncular tract Oculomotor nuclear complex (III)

Stria medullaris


White matter

ANTERIOR COMPLEX





THALAMUS

Cingulum

Anterior commissure

Stria medullaris and habenulo-interpeduncular tract

A

R

x(

5

Tenia tecta?


Medial habenular nucleus?

6

Bed nucleus of the stria terminalis?

SEPTUM

Cerebellar fissures

3

Third ventricle

Corpus callosum (genu) Cingulate gyrus

missure

Choroid plexus

4

4 2 14

l com

A

pr

m om ec

a amp poc p i H

al) ur iss

Fo rn i

Co rp u (b s ca od llo y) su m

Induseum griseum

Ca v se e o pt f t um h e

3

Central canal (spinal cord) Ependyma

13

13 Folium VIIa

300



301

PLATE 202B

Cingulum

Cingulate gyrus

SEPTUM


Islands of Calleja (in medial shell of nucleus accumbens)

MammilloBed nucleus of thalamic the stria terminalis

PREOPTIC AREA

1

White matter

11

Olfactory tubercle

Supraoptic nucleus

Optic nerve (II)


Red nucleus


D


E


Principal olive Dorsal accessory olive

MEDULLA

Inte

Fas n u c t ig ia l leus ?

8

9

Py dec ramid uss al atio n

Culmen IV, V

De nt a

B

E

B

CEREBELLUM (LATERAL VERMIS) Declive VI

rpo sit u

INFERIOR LOBE

Nodulus X

7

A

C

POSTERIOR LOBE Uvula IX

D

N CE

Pyramis VIII

Paraflocculus (HIX)

Dorsal motor nucleus (X) Solitary nucleus? Gracile nucleus

SPINAL CORD Ventral funiculus (spinal cord)

e

Choroid plexus

Reticular formation


cl

Fourth ventricle


Accessory nucleus (XI)

Centralis III

10

E

us cle nu te ucleus sn

6


Germinal trigone Subpial granular layer


A

R LOB

Inferior cerebellar peduncle?

lear r nuc bula Vesti complex

Reticular formation

N

T

IO ER

Lingula I, II

un

Medial lemniscus

Pontine and medullary glioepithelium/ependyma Cerebellar glioepithelium/ependyma

Su pe ri

ed


C


Central nucleus

ebel l a r p cer or



Inferior colliculus

PONS



B

Deep white layer

Locus coeruleus

Pontine gray



TECTUM


Arcuate nucleus (medulla, infiltrated by the Raphe migration)

A

Lateral lemniscus




Central gray

Reticular formation



Deep gray layer

Substantia nigra



Middle white layer

Reticular formation


1 2 3 4 5 6 7 8 9 10 11

Superficial and middle gray layers

Mesencephalic nucleus (V) Parabrachial nucleus

TEGMENTUM

Optic tract

Optic nerve layer

Superior colliculus

MI DB RA IN RAIN


cle un ed lp ra reb Ce

Olfactory peduncle

Forel's fields Medial forebrain bundle


HYPOTHALAMUS

1


PERIVENTRICULAR COMPLEX

tract

Magnocellular preoptic nucleus

Orbital gyrus

Dorsomedial Pa ra nucleus ce nt ra ln uc ANTERIOR leu CENTRAL COMPLEX s COMPLEX

Fasciola cinereum



Anterior commissure


4

Dorsolateral nucleus DORSAL COMPLEX


Cerebellar fissures


Stria medullaris

E


5

LOB


Third ventricle

Gracile fasciculus

AL

11

3

Choroid plexus

T

C

Folium VIIa

Tuber VIIb

R

(precommissural)

A

3 Fornix

Pr et ec tu m

2

Cave of the septum

10

302



303

PLATE 203B Stria medullaris Choroid plexus

gul um

Stria terminalis


1

Nucleus accumbens

Ante med ronucleial us

Fore l's fi elds?


HYPOTHALAMUS

Olfactory tubercle

Layer I

Cortical plate

Lateral hypothalamic area Supraoptic nucleus

cle

us

er

eb

ra

11

Occipital lobe

um ect t e Pr

Parabigeminal nuclei (dorsal and ventral) Dorsal nucleus of the lateral lemniscus Lateral lemniscus

l pedun c

Ventral nucleus of the lateral lemniscus Principal sensory nucleus (V) and nerve V bundles

le

Dentate nucleus lear lar nuc Vestibu x comple Spinal d us an nucle )

Pontine gray

PONS

Motor nucleus (VII)


7

8

(V tra ct lar ticu n Re matio for

Superior olive complex (periolivary nuclei)


neuroepithelium and subventricular zone 5 Accumbent (intermingled with the rostral migratory stream) 6 Strionuclear neuroepithelium and subventricular zone 7 Pontine glioepithelium/ependyma 8 Cerebellar glioepithelium/ependyma 9 Germinal trigone 10 External germinal layer 11 Subpial granular layer

Principal olive

MEDULLA

Floccular peduncle

Paraflocculus (HIX)

lobule (HVIIB)


External cuneate nucleus?

Cuneate fasciculus? Spinal nucleus and tract (V)

Nerve XII? (roots)

Lateral funiculus (spinal cord) SPINAL CORD

CEREBELLUM (HEMISPHERE) Ansiform lobule crus I (HVIIA)

Ansiform lobule crus II Paramedian (HVIIA)

Cuneate nucleus



9


Choroid plexus

Frontal stratified transitional field Callosal glioepithelium

Primary fissure





170

Anterior lobe (HI-HV)

Entorhinal cortex


1 2 3 4


Substantia nigra



11

Superior colliculus

VENTRAL HIPPOCAMPUS


Fasciola cinereum


TEGMENTUM

Subiculum

Orbital gyrus

nu

Pulvinar

Medial lemniscus

11

White matter

CENTRAL COMPLEX


SUBTHALAMUS TECTUM Subthalamic M ID BR AIN Inferior nucleus colliculus Reticular formation

C

Optic tract

1


l

3

2

ter na lc ap su le

ANTERIOR COMPLEX

ra

Corona radiata

BASAL GANGLIA

THALAMUS

t cen


In Anterior commissure


a Par

5

ar ul s tic leu Re uc n

6

Lateral ventricle

Ventral posterolateral nucleus Ventral lateral POSTERIOR nucleus COMPLEX

Dorsomedial nucleus



VENTRAL COMPLEX

DORSAL COMPLEX

Do rs nucolater le u a l s

Stem cells of the choroid plexus?

4

C in

Cin gul ate

gyr us

Frontal lobe

10 7

304



305

PLATE 204B Stem cells of the choroid plexus?

10

nu

N

s

E

ali

in er m

to r ie Pa Calcarine sulcus

BT

us

HA

LA

MU

S



Substantia nigra

ic

al pl at e

AM C Y Baso GD lat era AL lc A o

rt

Layer I

12

Primary fissure

6 al hin to r t e x n E co r

Ventral cochlear nucleus?

ce re


i or

PONS

u nc ped r lla be


Nerve V (root)

Inf er

Damaged area

e lob r o i V) ter An (HI-H



le

Ansiform lobule crus I (HVIIA)

Dentate nucleus

Superior vestibular nucleus

Fourth ventricle (lateral recess) Floccular peduncle

erebellar tracts?


13

re b

n oc Spi


White matter

Co


Occipital lobe

Zona incerta

lar rebel ior ce Infer peduncle

Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Alvear glioepithelium

s yrurea) g e at l a gul lenia us n i p u lc C ros al s t t i c ip (re -oc

DORSAL HIPPOCAMPUS

le


m ulu

uc

Ce

Optic tract

ng

m p

(a nt er io r

ule

V

ln

ps

tra

ca

cen

Int ern al

P ara



Centromedian Ventral nucleus posteromedial nucleus

Ci

us yr g ral p e d c l e al un mp plex a m o oc lc ipp dia e h x Subiculum le ra om Pa tic or 7 VENTRAL 8 HIPPOCAMPUS




SU

Subthalamic nucleus



leus

7 8 9 10 11 12 13

l n uc

Medullary lamina


6

tera


le


13

1 2 3 4 5

r

psu

Nucleus accumbens


Orbital gyrus

eti cu la

a

Pulvinar

CENTRAL COMPLEX

Diagonal band of Broca (horizontal limb)

Olfactory tubercle

3

rn



THALAMUS

) us cle

1

Anterior commissure

(R


ca

2


T

l

1

BASAL GANGLIA

te

nu

Caudate (head)

In

Ventral Anterior nucleus L

4

b) lim

AL

BE

9

t

R E TI C U L A R

S

ia tr

T

R

COMPLEX

l la

10

Induseum griseum?

Fornix

AL R S EX DOMPL teral a CO Dorsolcleus

11

4

PO CO ST M ERI PL O EX R

Lateral ventricle

5

Choroid plexus

a ntr Ce

Co

rp us ca llo su m

4

Choroid plexus

Paraflocculus (HIX)



Ansiform lobule crus II (HVIIA)


12

306



307

PLATE 205B Remnants of the germinal matrix, migratory streams, and transitional fields 1 Rostral migratory stream (source area) 2 Frontal neuroepithelium and subventricular zone 3 Frontal stratified transitional field 4 Callosal glioepithelium 5 Fornical glioepithelium neuroepithelium and 6 Occipital subventricular zone 7 Occipital stratified transitional field 13

Choroid plexus

p

pa lg yr us

N

POS TER COM I PLEOR X

en t

r al Medial l at era cl ln geniculate eu ucl e Subus body s) thalamic nucleus

C e re b r a l p

cl edu n

e

Calcarine sulcus

Ammon's horn

9

16

15

VENTRAL HIPPOCAMPUS

En

to

na rh i

l co

r te

x

Nerv eV( root)

l tra


ca

l

pl

at

White matter

7

e

Primary fissure


e lob r o i V) ter An (HI-H Middle cerebellar peduncle

n Ve

16

ti

Subiculum

co

c hl

ear

nucle

Dorsal cochlear nucleus us

Strionuclear glioepithelium External germinal layer

6

10

8 Damaged area

Occipital lobe

Layer I

lex Lateral ventricle

AM om YG Baso DA lat e ra l c LA om

Co rt ic

E

r ia ter m Posterior lim ina b li s

St

le ( an ter ior lim b) p su

l ca

(C

Subiculum

or

ter na

nu

s m ru ea) lu y u g s ar ng e lcu Ci a t n ia l su l l a u e it ng pl cip oc Ci tros o et (re Pari

Ammon's horn

C

In

r

X

E


la

PL


u

Dentate gyrus

Subgranular zone Amygdaloid glioepithelium/ependyma

Ventral postero- Suprageniculate nucleus medial nucleus

M CO

Amygdalohippocampal area Optic tract

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Alvear glioepithelium

ic


Dentate gyrus

Pulvinar

THALAMUS

AL

11

R

Fornix

COMPLEX

AL

TR

x ple om c l

T

4

DORSAL HIPPOCAMPUS


CEN

y tor fac ercle SUBSTANTIA l O ub t INNOMINATA

et

u l e p s

Medullary lamina Basal nucleus of Meynert


(

16

T ca


L

Anterior commissure

ia ed

Orbital gyrus

8



3

l

R


Nucleus accumbens

a

E

1

t e r n

Ventral Anterior nucleus

B

2



R

BASAL GANGLIA

1

Stem cells of the choroid plexus? Ventral posterolateral nucleus

V

RETICU L A

I n

Caudate (head)

L DORSAEX L l P M O C tera Dorsola s nucleu

12

Lateral ventricle

5

Pa ra hip po ca m

13

14

4

Co rpu s ca llos um

4


fe In

r io


peduncle llar e b ere Dentate nucleus rc

Flocculus (HX)

Choroid plexus

Paraflocculus (HIX)


Ansiform lobule crus II (HVIIA) Paramedian lobule (HVIIB)


15

308



309

PLATE 206B Germinal and transitional structures in italics Corpus ca llosum

Choroid plexus

Fimbria

Fornix Stem cells of the choroid plexus?

Dentate gyrus

(ant erio r lim b)

N E

u


Medullary lamina Ansa lenticularis

e re

bral p e d


AM YG DA LA l a o t s e r al a

mp

Lateral ventricle


Amygdaloid glioepithelium/ependyma Damaged area

sul cus


Occipital lobe

Occipital neuroepithelium and subventricular zone Layer I

C

White matter or

tic

al

pla

te


Temporal lobe



Primary fissure

Ammon's horn



Subgranular zone

A


Frontal lobe Frontal neuroepithelium and subventricular zone

Subgranular zone

VENTRAL HIPPOCAMPUS

B


le x


Dentate gyrus

Subiculum

u

Subiculum

Co

comp lex

Olfactory tubercle

rticomedi al c o

Orbital gyrus

C Optic tract




l

al c

ern

Int

Nucleus accumbens

Auditory radiation?

le

Int .

ule

ps


s)


Anterior commissure

a ps

ca

le u

THALAMUS

e


uc

rn

BASAL GANGLIA

Caudate (head)

BE LT (R eti In t e cu rn al

la





Ca lca rin e

nc

AR

R

V

UL


AL

Ammon's horn

Pulvinar

COMPLEX

IOR TER POS MPLEX CO

RET IC

St r ia t psule (posterior erm ca lim ina b) lis


T

DORSAL HIPPOCAMPUS

Par ahi ppo cam pal gyr us



pit al su lcu s


Fornical glioepithelium Lateral ventricle

(re Cing tro ul sp ate len gy ial ru Pa rie ar s toea oc ) ci


b lo ) r io HV r te I n (H

Dentate nucleus

e


le e nc dl u id ped M ar ell Flocculus eb r (HX) ce

Parahippocampal neuroepithelium and subventricular zone Alvear glioepithelium

Paraflocculus (HIX)

Choroid plexus

Ansiform lobule crus II (HVIIA)

Paramedian lobule (HVIIB) Biventral lobule (HVIII)


310



311

PLATE 207B Paracentral stratified transitional field




Co

Corona radiata

rpu s ca llos um

Lateral ventricle Callosal glioepithelium

Frontal lobe


Ventral striatum


AM


x

com pl e

Orbital gyrus

r al


Basol a te

e

DA LA

plat

L

A

TR VEN

O p tic

Amygdaloid glioepithelium/ependuma

Lateral ventricle

Pulvinar


Pulvinar


Medial geniculate body?

Ammon's horn


Ammon's horn

Dentate gyrus

DORSAL HIPPOCAMPUS Subiculum

t ac c tr i t Subiculum Op

VENTRAL HIPPOCAMPUS

Dentate gyrus

Fimbria

Subgranular zone

tract

Central nucleus

Co

YG

cal

An sa len ticu lar is SUBSTANTIA INNOMINATA


White matter

rti

Cerebral peduncle

Fornical glioepithelium Fornix


Auditory and visual radiations?


Anterior commissure

Choroid plexus

Pa ra hi pp oc am pa lg yr us

le su

ap

lc na

er nt

Putamen

rticomedi al c o m ple x

Co

Medullary lamina

Ste cho m cell roid s of ple the xus ?

lim (an ter ior

e

Layer I



LEX

THALAMUS

s) leu nuc

ul



Orbital gyrus

l ar

ps

I

tic u

BASAL GANGLIA

C

P OM


IOR TER POS MPLEX CO

(R e

b)

ca

Frontal lobe

al



T BEL

rn

Corona radiata

is minal Reticular nucleus a ter S t ri mb) ior li s ter (po

te

Caudate (head) Rostral migratory stream (source area)

In

Damaged area

le psu ca l a rn

In te


Caudate (body)

L AR ICU RET

m iu el h it ep ne o ur zo ne lar l a u at ic tri entr s al v er sub t a ol nd er a t An

Temporal lobe

Subgranular zone

Parahippocampal stratified transitional field Parahippocampal neuroepithelium and subventricular zone

312

PLATE 208A



313


Parietal stratified transitional field Paracentral stratified transitional field


Parietal lobe

Frontal lobe

Corona radiata


Corona radiata

n al

cap

s ul

e(



a te

fa s

cic


Ventral striatum u lu

s

o mary lfac Pri ac olf al r e t

y cortex tor


c in

tory tr

La

Un

LA A D

AM

YG

Lateral nucleus


SUBSTANTIA INNOMINATA le u s l nuc t BasaMeyner of

Central nucleus

m Ste

a Ans t S tr ia

le n ti

erm

c u la

in a li

r is

s

Choroid plexus

Pulvinar

Stratum oriens Fimbria

Dentate gyrus

geniculate body

? us us lex Fimbria p lex d p i o id or o h r o ec Ch f th CA3 o lls ce

Lateral ventricle


CA3 OR I R EX TE PL S PO OM HIPPOCAMPUS C Lateral

e

Orbital gyrus


Au dit o ra ry a RET dia nd ICUL tio vi AR ns su ? al

e

at


THALAMUS

sul

pl

A com nteri mis or sur e

cal

t ac

Corti

Ex ter na lc ap Cl sule au str um

ticular nucleus) (Re T L BE

Lateral ventricle

Stria terminalis

Interna l ca p

White matter

Caudate (tail)

BASAL GANGLIA Putamen

Layer I


b)

Putamen Corona radiata

po ste rio

im rl

r I n te

cap

s ul

Inter n al

b) r lim o i r nte e (a

CA1

Pyramidal layer Stratum radiatum Stratum lacunosummoleculare


Molecular layer Granular layer

Subgranular zone Hilus

Lateral ventricle

CA1

Ammon's horn Temporal neuroepithelium and subventricular zone


314



315


Corona radiata

Insular gyrus

Insular gyrus

Frontal lobe

Claustrum Damaged areas

Claustrum Orbital gyrus

) tream ory s t m a r u g r i st Claue lateral m th y b d te External capsule filtra on in (regi


Lateral fissure

Insular gyrus

co r t e x

t

tory

ra c

ar im

Pr

do n u p ir if c le o r m us

yo

lfac

cto ry t lf a

lo

Lat a er

Putamen

Uncinate fasciculus

re ssu

ior

er nt

i mm

co

A

Lateral nucleus?


M A

LA A D G Y

Central nucleus

e Int

Ventral striatum

C

or

at

e

Layer I

capsule

Choroid plexus

Strionuclear glioepithelium Fimbria


sub ven tr

Temporal lobe Subpial granular layer

Choroid plexus


Lateral ventricle

ic u la Tem r zone por al str ati fie

ti

pl

rnal

lis ermina Stria t

s rminali Stria te

White matter

l

Caudate (tail)


Temporal n euroepi thelium and

Damaged area

ca


BASAL GANGLIA

En



d tr

a ns

Lateral ventricle

iti o n

a l fi

e ld

316

PLATE 210 GW26 Sagittal, CR 225 mm, Y147-63 Level 2: Section 481 CEREBELLUM, ANTERIOR LOBE, LINGULA

See the entire section in Plate 191 and a medium magnification view in Plates 201A and B.

Granule cells (settled)

Lingula Layer of settled granule cells (contains migrating Purkinje cells and glia)

Layer of settled Purkinje cells

Medullary layer (contains migrating Purkinje cells and glia) Purkinje cell (migrating)

Settling basket and stellate cells?



Molecular layer

(contains migrating granule cells and settling basket and stellate cells)


External germinal layer (premigratory zone) External germinal layer (proliferative zone)


317

PLATE 211 GW26 Sagittal, CR 225 mm, Y147-63 Level 2: Section 481 CEREBELLUM, ANTERIOR LOBE, CULMEN


Culmen



Purkinje cell (migrating) Settling basket and stellate cells? Medullary layer (contains migrating Purkinje cells and glia)

Layer of settled granule cells (contains migrating Purkinje cells and glia)

Purkinje cells (settled) Granule cells (migrating)

Purkinje cell (migrating)

Layer of settled Purkinje cells Molecular layer



External germinal layer (premigratory zone) External germinal layer (proliferative zone)


318

PLATE 212 Declive

GW26 Sagittal, CR 225 mm, Y147-63 Level 2: Section 481 CEREBELLUM, CENTRAL LOBE, DECLIVE


External germinal layer (proliferative zone) External germinal layer (premigratory zone)

Medullary layer

(contains migrating Purkinje cells and glia)

Layer of settled granule cells


Layer of settled Purkinje cells Molecular layer






Purkinje cells (settled) Granule cells (settled) Purkinje cell (migrating)

319

PLATE 213 See the entire section in Plate 191 and a medium magnification view in Plates 201A and B.

GW26 Sagittal, CR 225 mm, Y147-63 Level 2: Section 481 CEREBELLUM, POSTERIOR LOBE, UVULA Purkinje cell (migrating)

External germinal layer (proliferative zone) External germinal layer (premigratory zone) Medullary layer

Uvula Molecular layer


Purkinje cell layer absent






Layer of settled Purkinje cells (fragmented) Purkinje cells (settled)


Layer of settled granule cells (contains migrating Purkinje cells and glia)


320

PLATE 214 See the entire section in Plate 191 and a medium magnification view in Plates 201A and B.

GW26 Sagittal, CR 225 mm, Y147-63 Level 2: Section 481 CEREBELLUM, INFERIOR LOBE, NODULUS External germinal layer (proliferative zone)

Nodulus Purkinje cells?

External germinal layer (premigratory zone)

(large group migrating in the medullary layer)

Purkinje cells (migrating)




Medullary layer (migrating cells aligned with fibers) Layer of settled granule cells Layer of settled Purkinje cells Molecular layer External germinal layer


321

PLATE 215 GW26 Sagittal, CR 225 mm, Y147-63 Level 2: Section 481 CEREBELLUM Germinal Trigone


1 Germinal trigone (at base of the Nodulus)

Source of the external germinal layer earlier in development

Dense cell clusters that may be premigratory cohorts of glia and Purkinje cells

2 Germinal source of the choroid plexus

Remnant of the cerebellar neuroepithelium

3

322

PART PART IX: IX:


Su p

ior er

TE

s ulc u

Postcentra ls

gyru s

n t r al

sulcu s

Postc e

Centr al

e n tra

Prec

fro nt rio r pe

M id d fr l

Su

NTAL LOB FRO E

Insular gyrus

La

l t e ra

re fissu

us l gyr a r o p tem

M i d d le a n d i n f e r

ior

yri oral g p m te

ITAL LO CIP BE OC

The approximate cutting plane of this brain is indicated in Figure 13 (facing page) with lines superimposed on the GW26 brain from the Larroche (1967) series. The anterior part of each section (on the left) is dorsal to the posterior part (on the right). As in all other specimens, the sections chosen for illustration are more closely spaced to show small structures in the diencephalon, midbrain, pons, and medulla. Illustrated sections are spaced farther apart when they contain only large brain structures, such as the cerebral cortex, basal ganglia, and cerebellum. Photographs of 17 different Nissl-stained sections (Levels 1-17) are shown at low magnification in Plates 216-229. The core of the brain and the cerebellum are shown at high magnification in companion Plates 230AB-244AB for Levels 3-17.

Orbital gyri

l and a argina ng m a r Sup

al occipital gyri t er La

This specimen is case number W-16-59 (Perinatal RPSL) in the Yakovlev Collection, a premature stillborn female infant. The brain is classified as a Normative Control in the Yakovlev Collection (Haleem, 1990). It was cut in the horizontal plane in 35-µm and 15-µm thick sections. Since there is no available photograph of this brain before it was embedded and cut, the photograph of the lateral view of another GW26 brain that Larroche published in 1967 (Figure 12) is similar to the features of the brain in Y16-59.

lobule

r gyri ula

rior e f in nd gyri a e ta l on

PARIET AL LO Superior B parietal

E

s ru y g al

l gyru s

TRAL N E C PARA BULE LO

M P ORAL LOB E Pons


Medulla

Figure 12. Lateral view of a GW26 brain with major structures in the cerebral hemispheres labeled. (From the photographic series of: J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 254.)

323

GW26 HORIZONTAL SECTION PLANES 1 2

EL N

UM

BER

3 4 5

6 7

240

LEV

8 9 10 11

340 400

12 13 14 15 16 17

NUM BER

460 520 560

SEC TIO N

620 660 700 740 780 820 860 880 900 940 960

Figure 13. Lateral view of the same GW30 brain shown in Figure 12 with the approximate locations and cutting angle of the sections of Y16-59. (From the photographic series of: J. C. Larroche (1967) Maturation morphologique du système nerveux central: ses rapports avec le développement pondéral du foetus et son age gestationnel. In: Regional Development of the Brain in Early Life, A. Minkowski (ed.), London: Blackwell, page 254.)

Y16-59 contains more prominent immature structures than in the older specimens. A densely staining and more thick neuroepithelium/ subventricular zone (than the GW30 horizontal specimen) is generating neocortical interneurons and glia in all lobes of the cerebral cortex. The same thickness variations between the occipital and other lobes of the cerebral cortex are still there, however. Remnants of migrating and sojourning neurons and/or glia are visible in all lobes of the cerebral cortex as stratified transitional fields. Many neurons, glia, and their mitotic precursor cells are still migrating through the olfactory peduncle toward the olfactory bulb (rostral migratory stream) from a presumed source area in the germinal matrix at the junction between the cerebral cortex, striatum, and nucleus accumbens. Within the cerebral cortex, definite streams of neurons and glia are in the lateral migratory stream that percolates through the claustrum, endopiriform nucleus, external capsule, and uncinate fasciculus. These cells appear to be heading toward the insular cortex, primary olfactory cortex, temporal cortex, and basolateral parts of the amygdaloid complex. In the basal ganglia, there is a thick neuroepithelium/subventricular zone overlying the striatum and nucleus accumbens where neurons are being generated; at least three subdivisions (anteromedial, anterolateral, and posterior) can be distinguished in the striatal part. Another region of active neurogenesis in the telencephalon is the subgranular zone in the hilus of the dentate gyrus that is the source of granule cells. Other structures in the telencephalon, such as the septum, fornix, and Ammon’s horn part of the hippocampus, have only a thin, darkly staining layer at the ventricle, and these are presumed to be generating glia, cells of the choroid plexus, and the ependymal lining of the ventricle. Most of the structures in the diencephalon appear to be settled and are maturing, but the third ventricle is lined by a more densely staining glioepithelium/ependyma than in the older specimens. A convoluted glioepithelium/ependyma lines the cerebral aqueduct in the midbrain that continues into the anterior fourth ventricle. A smooth glioepithelium/ ependyma lines the fourth ventricle through the remainder of the pons. A convoluted glioepithelium/ependyma lines the floor of the fourth ventricle through much of the medulla. The external germinal layer is prominent over the entire surface of the cerebellar cortex and is actively producing basket, stellate, and granule cells. The cerebellar cortex itself shows less definition between hemispheric lobules. The germinal trigone is at the base of the nodulus and along the floccular peduncle; choroid plexus cells and glia may still be originating here. In the lower medulla and spinal cord, this specimen is remarkable for showing dense myelination gliosis in the cuneate fasciculus.

324

PLATE 216

Postcentral gyrus

Central sulcus


Precentral gyrus Middle frontal gyrus

Pa

b u le

1 2 3 4

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 5 Parietal stratified transitional field Frontal stratified transitional field 6 Paracentral neuroepithelium and subventricular zone Callosal glioepithelium, neuroepithelium, subventricular zone, 7 Paracentral stratified transitional field and stratified transitional field of the cingulate cortex Parietal neuroepithelium and subventricular zone 8 Subpial granular layer (cortical)

ra

Par ieta l

lo


c e n t ral

7 Frontal lobe

6 3

C i n g u l a t e Superior frontal gyrus

8

5

5

2

1

lo b e

g y r u s Precuneus


3


Corpus callosum

Lateral ventricle

2

1

6 7

Choroid plexus

4 5 White matter Cortical plate Layer I

325

PLATE 217 Remnants of the germinal matrix, migratory streams, and transitional fields Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Subpial granular layer (cortical)

Supramarginal gyrus

Postcentral sulcus Postcentral gyrus

Angular gyrus

Central sulcus Precentral gyrus

b u le

Pa

ra

c e n t ral

Internal capsule

Th

ntr ic

le

e m (g

osu

Fornix

all

sc

Co

1

u rp

3 8

us


Fornix

9

10

Caudate

Thalamus Putam

en

iu

le n


m

Fornix

4

n

u)

Cingulate gyrus

a la

Ch

a

Lat era l ve

Basal ganglia

sp ll o u m ( s

11

Frontal lobe

Pa rie tal

Insular gyrus

lo

Superior and middle frontal gyri

Lateral fissure

sc

7 8 9 10 11

id oro

rpu

Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Fornical glioepithelium Parietal neuroepithelium and subventricular zone Parietal stratified transitional field

Stria terminalis


lob e

us

gyr

Interhemispheric fissure m

Precuneus

)

La te ra lv en tr icl e

3

Choroid plexus

7

External capsule Claustrum

late

gu Cin

2


xus ple

Co

1 2 3 4 5 6


6


5

6

icle entr ral v Late

5 Layer I


326

PLATE 218 8 9 10 11 12 13 14 15

Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Callosal glioepithelium Callosal sling Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Occipital neuroepithelium and subventricular zone

Occipital stratified transitional field Parietal neuroepithelium and subventricular zone Parietal stratified transitional field Posterior striatal neuroepithelium and subventricular zone Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Subpial granular layer (cortical)

Postcentral sulcus

Supramarginal gyrus

Postcentral gyrus

Angular gyrus

Central sulcus

Pa

c e n t ral

)

nu


12

13

2

Internal capsule (anterior limb) External capsule Claustrum Stria terminalis

Dorsal complex Anterior complex

Re

Ventral t ic ula complex rb e lt Bas al g ang lia

11

pus Hippocam

Cingulum

14

5

Co

1

Choroid plexus

Fornix

Posterior complex

3

4

Septum

ip

c

s

us

tal l o

Late ral v entr icle

Choroid plexus

Oc

g yru

Th

Par ie

b

Cin Retr gulate gy osple nial arus rea

ulate

ve nt ric le

m ala

lim

nium) call o s u m (sple

Cing

men caps al ern I nt

P u ta

An ter ior lim C au b dat e

e ul

r r io ste Po

rpu s

La ter al

In s

yrus ular g

Co

Frontal lobe

ra

Superior parietal lobule?

Lateral fissure

lo

Superior and middle frontal gyri

b u le

Precentral gyrus

a ll o s u m ( g e

1 2 3 4 5 6 7

us c



rp


15

it a

l lobe


Occipital lobe

6

be

8

7

9 10 White matter Internal capsule (posterior limb)

Layer I

Cortical plate

327




Anteromedial striatal neuroepithelium and subventricular zone Strionuclear glioepithelium Subpial granular layer (cortical)


Lateral fissure Postcentral gyrus Central sulcus Precentral gyrus Superior and middle frontal gyri ra b c e n t ral l o e

16

1

13

2

14

Dorsal complex nt ra Ve x lc n o m ple R tral et icu com lar ple be x lt

Ba sal ga ng lia

pus

Cingulum

C

15

Anterior complex

am

Septum

Fornix

Occipital lobe

Occipital Third ventricle Retrosplenial gyri cortex Interhemispheric fissure Choroid plexus Habenula Parahippocampal gyrus

Ce

3

us am l a Th

Choroid plexus

Parie tal lo be

poc

4

lim b

n u am e ps us s l ca b o u a Gl llid ern pa Int

b Hip


Put

im rl r io te s Po

Posterior complex

Cingulate gyrus

Cau dat e ve nt ric le

gyrus Insular le

Pa

Frontal lobe

La ter al

An ter ior

Angular gyrus

be oral lo Temp

ul



nu



(ge

Fornical glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Occipital neuroepithelium and subventricular zone


c a ll o s u m



p us


9 10 11 12 13 14 15 16

or


)

1 2 3 4 5 6 7 8


10 11

Internal capsule (anterior limb) External capsule Claustrum Stria terminalis Internal capsule (posterior limb)

6

5 8

12 9

7 e L at

ral

le tr ic ven


328

PLATE 220

Superior temporal gyrus Lateral fissure


Temporal lobe lim b

Choroid plexus


Po ste r io r

Insular gyrus

Hippocampus

Late ral v entr icle


Cingulate gyrus Corpus callosum (genu)


3

1

Septum

14 15 16

Cerebral aqueduct

Periventricular complex Central complex

ex pl om lc ra b e l t nt Ve ular tic

Cingulum

Bed nuc. of the stria terminalis

Fornix

Re

4

e

r rio x ste ple Po om c

a gli Parahipen n m a pocampal a t Pu g gyrus l An ter asa ior La s B l ter i u m Ca b m al ud ve ate ala Midbrain nt h ric tectum Third ventricle T l

Frontal lobe

le


1 2 3 4 5 6 7 8

Remnants of the germinal matrix, migratory streams, and transitional fields Frontal neuroepithelium and subventricular zone 9 Temporal stratified transitional field 10 Alvear glioepithelium Frontal stratified transitional field 11 Subgranular zone (dentate) Callosal glioepithelium 12 Lateral migratory stream (cortical) Fornical glioepithelium Parahippocampal neuroepithelium, subventricular 13 Posterior striatal neuroepithelium and subventricular zone zone, and stratified transitional field 14 Anterolateral striatal neuroepithelium and subventricular zone Occipital neuroepithelium and subventricular zone 15 Anteromedial striatal neuroepithelium and subventricular zone Occipital stratified transitional field 16 Strionuclear glioepithelium Temporal neuroepithelium and subventricular zone 17 Subpial granular layer (cortical)

G p a lo b lli us du In s te rn al ca ps u


2

10 11

7 6

Occipital lobe


Posterior commissure Superior colliculus

5

12

17


Layer I

13

External capsule Claustrum Stria terminalis Internal capsule (posterior limb)

8

9


329


Anterolateral striatal neuroepithelium and subventricular zone Anteromedial striatal neuroepithelium and subventricular zone


Strionuclear glioepithelium Subpial granular layer (cortical)



Bed nuc. of the stria terminalis

r gyru

Putam

Co An rp te us Ca rior l ca im ud llo b ate su m (ro Subcall str osal are um a )

s

en

Ba

a lg


pallidus

Hippocampus

Zona incerta

Tectum

Anterior commissure

un ed lp

Superior colliculus

Subthalamic nucleus

16

5

10 9

cl e

3


Cerebral aqueduct

ra

14 15

Occipital lobe

Midbrain

Forel's fields

reb

2 1 13

6

Third ventricle

Fornix

4

6


Ce

Lateral ventricle

n

a g li

sa Globus

Septum


Post e r io r lim

Insula

Frontal lobe

s mu ala Th


Temporal lobe b


lc ap la m s u l e us



rn a



ha

Callosal glioepithelium Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Occipital stratified transitional field


te



bt


9 10 11 12 13 14 15 16

In


Su

1 2 3 4 5 6 7 8


11 Internal capsule (anterior limb)

Layer I

12

External capsule Claustrum Stria terminalis Internal capsule (posterior limb)

7

8 White matter

Cortical plate

330

PLATE 222



Rostral migratory stream (source area) Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Alvear glioepithelium Subgranular zone (dentate)

9 10 11 12 13 14 15

Lateral migratory stream (cortical) Posterior striatal neuroepithelium and subventricular zone Accumbent neuroepithelium (intermingled with the rostral migratory stream) Diencephalic (hypothalamic) glioepithelium/ependyma Mesencephalic glioepithelium/ependyma External germinal layer (cerebellar) Subpial granular layer (cortical)


Middle and inferior temporal gyri

Temporal lobe


Choroid plexus

rus

r gy

ula Ins

Frontal lobe


Basal ganglia

C au date Corp us ca accNucle llosum um us (rostr ben um ) s Subcallosal area


12


2

1 11

Lateral ventricle

Hippocampus

Ante rior Puta com me Su mi n ssu inn bsta re om ntia ina er ta eb r al Su p bt ha edu lam n c us l e



Midbrain

C Tegmentum Central Tectum Preoptic gray area Hypothalamus Inferior Red Third ventricle nucleus colliculus Cerebral aqueduct Subthalamic nucleus Optic tract

13

Lateral lemniscus

8 7

4

3 9 Internal capsule (anterior limb) External capsule Claustrum Stria terminalis Internal capsule (posterior limb)

Cerebellum (vermis)

10

5

6

14


331

PLATE 223 Remnants of the germinal matrix, migratory streams, and transitional fields Rostral migratory stream Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Alvear glioepithelium

8 9 10 11 12 13 14

Subgranular zone (dentate) Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma Diencephalic (hypothalamic) glioepithelium/ependyma Mesencephalic glioepithelium/ependyma External germinal layer (cerebellar)




Temporal lobe

Lateral fissure Insular gyrus Orbital gyrus

Subcallosal area

11


3

2


Optic tract


Tegmentum

Tectum Central gray

Substantia nigra Amygdala

10

12

Red nucleus Inferior Cerebral aqueduct colliculus

Third ventricle

9


Midbrain

Hypothalamus

1

Lateral ventricle

Hippocampus

Amygdala

Frontal lobe

tia Substan ata innomin


Anterior commissure N accuucleus mben s

1 2 3 4 5 6 7


Cerebral peduncle

8 7

9

4

Cerebellum (vermis)

Lateral lemniscus

14

13 Layer I

6 5

13


332




Rostral migratory stream Frontal neuroepithelium and subventricular zone Frontal stratified transitional field Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field Alvear glioepithelium

8 9 10 11 12 13 14

Subgranular zone (dentate) Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma Diencephalic (hypothalamic) glioepithelium/ependyma Mesencephalic glioepithelium/ependyma External germinal layer (cerebellar) Subpial granular layer (cortical)


Lateral fissure Lateral ventricle

Orbital gyrus Hippocampus

Gyrus rectus

Frontal lobe

Amygdala Optic tract

Subcallosal area

3

2

Olfactory tubercle Primary olfactory cortex (piriform)

7

10 9 6 14

Cerebellum (vermis)

Cerebral aqueduct

Amygdala

Cerebral peduncle

8


Tectum

Midbrain

Substantia nigra

1

Lateral lemniscus

Tegmentum

Hypothalamus

11



Temporal lobe

4

12

Cerebellum (deep nuclei)

13 Layer I Cortical plate

5

13

White matter

333



2


3


4


5


6


7 8 9 10 11 12 13


Subgranular zone (dentate) Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma Diencephalic (hypothalamic) glioepithelium/ependyma Pontine glioepithelium/ependyma External germinal layer (cerebellar)




Temporal lobe Lateral ventricle

Lateral fissure a gdal Amy

Frontal lobe

Orbital gyrus

2

10

1

13 Primary olfactory cortex (piriform) Damaged area

Fourth ventricle

Substantia nigra

6

9 8

Pons

Midbrain

Tegmentum Hypothalamus

Cerebral peduncle

7

3

Locus coeruleus

Cerebellum (vermis)

11


4 Layer I

5


12

m ) llu lei be c re nu Ce eep (d

Olfactory peduncle


Parahippocampal gyrus Trochlear nucleus (IV)

Optic tract

Gyrus rectus Interhemispheric fissure

Hippocampus

12

334




2 3

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium, subventricular zone, and stratified transitional field

4


5 6 7 8 9

Lateral migratory stream (cortical) Amygdaloid glioepithelium/ependyma Pontine glioepithelium/ependyma External germinal layer (cerebellar) Subpial granular layer (cortical)




Damaged area

Amy

5

Orbital gyrus

Frontal lobe

gdala

Lateral fissure

Olfactory peduncle

Pontine gray Interpeduncular nuc.

1

Hypothalamus

Pons

Abcucens nucleus (VI)

Cerebral peduncle

4

6 Damaged area

lum ) bel uclei e r Ce ep n (de

3

2

9

Fourth ventricle


Locus coeruleus


Optic chiasm

Gyrus rectus


Trigeminal nuclei (V)

7 Superior cerebellar peduncle

Layer I White matter

Cerebellum (vermis)

Cortical plate

8 Inferior cerebellar peduncle

335




2

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium, subventricular zone, and stratified transitional field

3

4 5 6 7

Amygdaloid glioepithelium/ependyma Medullary glioepithelium/ependyma External germinal layer (cerebellar) Subpial granular layer (cortical)


Cortical plate White matter Inferior temporal gyrus Layer I Trigeminal nuclei (V) Vestibular nuclear complex

Temporal lobe

Damaged area

3 Lateral fissure Orbital gyrus

Frontal lobe

4

1

Ento

h in

r

Optic nerve

5

Hypothalamus

Lateral funiculus

Cerebellum (vermis)

Spinal cord

Medulla al c

e ort x

Damaged area

Fourth ventricle

Pons

Interhemispheric fissure Olfactory peduncle

Cuneate fasciculus


2

Pontine gray

Gyrus rectus

Gracile fasciculus

7

6 Inferior cerebellar peduncle Middle cerebellar peduncle Transpontine corticofugal tract

336


Remnants of the germinal matrix, migratory streams, and transitional fields 1 Rostral migratory stream 3 External germinal layer (cerebellar) 5 Dorsal funicular myelination gliosis 2 Medullary glioepithelium/ependyma 4 Subpial granular layer (cortical)

Level 13: Section 860 See detail of brain core and cerebellum in Plates 240A and B.

Inferior temporal gyrus Cortical plate

Nerve V (root) Superior olive complex

White matter


Temporal lobe

Gracile fasciculus

4

Layer I


Olfactory peduncle

Pons

1

Pontine gray

2

Fourth ventricle


Cuneate fasciculus Lateral corticospinal tract

5 Medulla Spinal cord

4

3 Inferior cerebellar peduncle Entorhinal cortex

Cochlear nuclei Middle cerebellar peduncle




Middle cerebellar peduncle Cochlear nuclei Inferior cerebellar peduncle

Temporal lobe

Cuneate nucleus Cuneate fasciculus

4

Gracile fasciculus Lissauer's tract Lateral corticospinal tract


Medulla

Pontine gray

4

Fourth ventricle

Pons

2


Layer I Superior olive complex

Ventral corticospinal tract

5 3

Spinal cord

337

PLATE 229 Remnants of the germinal matrix, migratory streams, and transitional fields 1 Medullary glioepithelium/ependyma 3 Subpial granular layer (cortical) 5 Ventral funicular myelination gliosis 2 External germinal layer (cerebellar) 4 Dorsal funicular myelination gliosis


Level 15: Section 900 Inferior temporal gyrus

See higher magnification view in Plates 242A and B.

Temporal lobe Cortical plate (Layers II-III)

Superior olive complex Motor nucleus (VII)

Layer I

3

2


Nerve V

Central canal (medulla)

4

Medulla


Spinal cord Central canal (spinal cord)

Pons


5

1

Pontine gray Inferior cerebellar peduncle Middle cerebellar peduncle Cochlear nuclei

2

Lateral corticospinal tract Cuneate fasciculus Spinocerebellar tracts Gracile fasciculus Spinal tract (V)


See higher magnification view in Plates 243A and B. 2

Cerebellum (hemisphere) Choroid plexus

Pons

Medulla


Spinal cord

5

Pontine gray Middle cerebellar peduncle Inferior olive complex


Pyramidal decussation Spinocerebellar tracts Raphe nuclear complex Lateral reticular nucleus


See higher magnification view in Plates 244A and B. Pons Pons Pontine gray Corticospinal tract Middle cerebellar peduncle Inferior olive complex

Medulla

Spinal cord Pyramidal decussation

5


338

PLATE 230A GW26 Horizontal, CR 235 mm, Y16-59 Level 3: Section 400


339

PLATE 230B Caudate (tail)

Lateral fissure

gyrus Insular

Choroid plexus

b

Frontal lobe

)

SEPTUM

C o rp

PL

M

O

en tr a

ll



Fasciola cinereum?

Dorsomedial nucleus

a te

ral

nucl e u s

Ventral lateral nucleus R et

ic u

l ar


nuc leu s


Subiculum


Pulvinar



Dentate gyrus

Ammon's horn

Glioepithelium


la te

Layer I

Band of Gennari (striate cortex)

Induseum griseum

C



R LA

Occipital lobe

laris Stria medul


Anteromedial

x rni Fo

C


al p

Fimbria

CENTRAL COM PL EX


C o r tic

THALAMUS

ium)

Cave of the septum

Anterolateral

White matter

L

p u s c a l l o s u m ( s p le n

u s c a ll o s u m

EX PL M C CO AL R NT VE

U

HIPPOCAMPUS

CU P E R I V EN T R I Subfornical organ? Choroid plexus (in roof of third ventricle)

Lateral septal nucleus Fornix

Fornical glioepithelium Callosal glioepithelium

Stria terminalis

Glioepithelium

ANTERIOR COMPLEX

Glioepithelium ix rn Fo

Callosal sling

A

E

Lateral ventricle

Fimbria/fornix

LT

DORSAL COMPLEX

um

Induseum griseum

I

Stria terminalis

Lateral ventricle

Cingulate gyrus

r

c

B

R

r

EX

(h e a d

n

te

l na

E

A

I

B

L

u

le

rio

C or

gul

d a te

r li mb

SA

s ap

ste Po


Cau

rio

IA

li m

POSTERIOR COMPLEX

An te

men A Puta G

L G N

R

Ex

T

strum Clauule l caps terna

Cin


Visual radiation

Cortical motor output (in internal capsule)

Paracentral lobule


Damaged area

Subpial granular layer Precentral gyrus

Postcentral gyrus Central sulcus

Parietal lobe Parietal stratified transitional field Parietal neuroepithelium and subventricular zone

340



341


Temporal lobe

Precentral gyrus Central sulcus Postcentral gyrus


Lateral fissure

um

Cingulate gyrus Induseum griseum?

r li mb

Ca uda te ( hea d)

B

A

Cave of the septum

SEPTUM


t

CO L A R OMPLEX NT LC E A V TR

Stria terminalis

Third ventricle

Ve nt r nu al a cl nt eu er s io r

Dorsomedial nucleus ra

ll

at

al er at l l us ra le us nt uc cle Ve n nu ar

Centromedian e ra ln nucleus u cl eus

ul

White matter

Thalamic and epithalamic glioepithelium/ependyma

nt


ti c


Choroid plexus (surrounding pineal recess of third ventricle)

Mammillothalamic tract?

Re

Anterolateral



PERIVENTRICULAR COM PLEX


HIPPOCAMPUS

Stria medullaris and habenulo-interpeduncular tract

Stria medullaris

Choroid plexus

Gl io ep ith eli um

Ce


DORSAL COMPLEX

ANTERIOR COMPLEX

Foramen of Monro

Anteromedial


L

Lateral septal nucleus Fornix

Fornix

Fornical glioepithelium Callosal glioepithelium

Stria terminalis

e T ul E L

CE N

gul

Corpus callosum

Cin

rio

A

Fimbria/fornix

r r io e t s Po Caudate (tail)

A LI

us ) s B llid ent a p R a THALAMUS m p A g us se l c L ob nal U l G ter EX na IC r PL (ex T e M

SA

In

An te

G

Choroid plexus

b lim

POSTERIOR COMPLEX

m Puta

NG

E

sule al cap n r e t x E en

Corticofugal fibers (in internal capsule)

trum Claus

R

Paracentral lobule

L ve ate nt ra ric l le

Lateral ventricle

gyrus Insular

po Ve ste n tr nu rola al c le te r us al


Pulvinar Subiculum Dentate gyrus

Cortical plate

Subgranular zone Ammon's horn

Layer I

Glioepithelium

Alvear glioepithelium Temporal neuroepithelium and subventricular zone




342



343

PLATE 232B Superior temporal gyrus Lateral fissure


Frontal lobe


L

G lidus nt) en m N a t Pu A s palegme

ior

lim



Cave of the septum

SEPTUM


Fornix

EX PL OM C R LA ANTERIOR I CU R T COMPLEX EN RI V PE Third ventricle Reuniens nucleus Anteromedial nucleus

Anteromedial Striatal neuroepithelium and subventricular zone


Re tic

Anterolateral

Central lateral nucleus

Vent ral n u cl la te ra l eu s


ar

us cle nu

Ventral posterolate rolateral ral nucleus ulate genic Supra ucleus n




ul



Ventra l an nucleuterior s


Superior colliculus



UM

Fo rn ix

Stria terminalis

LEX MP O C

MIDBRAIN TECTUM

e

Cingulate gyrus

B

THALAMUS


)

le s u LT E

ECT

icl

ad

A

PO CO STE M RI PL OR EX

ET

(h e

B

L

u s ina ob al lam Gl tern y r lla (ex

HIPPOCAMPUS

PR

a te

b

SA

G

Fimbria/fornix

Stria terminalis

IA

Me d (in Glo u te bu I n rn s p t e al s all r eg id R E T n a men us t) IC l U c M VE L a th am NT A p ala m R m illo RA ic L tra CO ct? M PL CEN TR EX AL

ud

tr en lv

ra

te

La

Ca

er

um Claustr

m liu he pit ioe Gl

An t

Pos te r io r lim b

Lateral ventricle

le l capsule Externa

ng ul um

Choroid plexus

Insular gyrus


Ci


Temporal lobe


White matter

Diencephalic (thalamic) glioepithelium/ependyma Subgranular zone Subiculum Dentate gyrus Ammon's horn


Cortical plate Glioepithelium Stem cells of the choroid plexus

Layer I

Caudate (tail)

Subpial granular layer Lateral migratory stream

(infiltrating the claustrum and entering the insular cortex)


Parahippocampal neuroepithelium and subventricular zone Alvear glioepithelium Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

344



345

PLATE 233B Inferior frontal gyrus

Lateral fissure

ad

Subcallosal area

SA

Zona incerta

e f th s o a lis u e u c l m in Fornix d n er Lateral B e tr ia t s septal nucleus

Tenia tecta (dorsal) Medial septal nucleus


Ansa lenticularis?

S

T UB

HA

M LA


MIDBRAIN

Mammillothalamic tract?

Forel's fields


Third ventricle

Central gray


Cerebral aqueduct

HYPOTHALAMUS

SEPTUM

US Superior colliculus TECTUM

)

(e Glo xt b er us na p l s all eg id m us en t) Me du l (in Glo te bu rn s In al pa te se lli gm du rn al en s t) ca ps ul e

(he

B

A


TE G M EN TUM

ate

r li mb

ry la

ina m la

S

ud

rio

L

G

L

HIPPOCAMPUS

MU

An te

men Puta

G AN

IA

Lateral ventricle

A A L IOR T H STERLEX PO OMP C

Claustrum le l capsule Externa

Ca


al ern t x E

Fimbria/fornix

e sul Glioepithelium cap

Posterio r limb

Insular gyrus

Lateral ventricle


Meyer's loop (visual radiation) Choroid plexus

Frontal lobe



Temporal lobe


Zonal and optic nerve layers Superficial gray layer

Anterior commissure



Deep white layer


cn mi

n du pe

ala

r al

bt h

Anterolateral

Deep gray layer

Su


Middle white layer

reb

eu

l

cle

uc


Anteromedial

Ce


Superficial white layer Middle gray layer


s


Subgranular zone

Subiculum Dentate gyrus Ammon's horn

Stria terminalis

White matter


Parahippocampal stratified transitional field Parahippocampal neuroepithelium and subventricular zone

Glioepithelium Cortical plate


Layer I

Subpial granular layer Lateral migratory stream (infiltrating the claustrum and entering the insular cortex and temporal cortex)

Caudate (tail)


Stem cells of choroid plexus?

Alvear glioepithelium Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

346



347

PLATE 234B Caudate (tail) Internal capsule (posterior limb)

Inferior frontal gyrus Lateral fissure


Choroid plexus Fimbria/fornix

Lateral ventricle


HIPPOCAMPUS

s

re issu

t

du

nc

le

Mammillothalamic tract? Paraventricular nucleus SupraDorsomedial mammillary area nucleus?

Lateral lemniscus


Red nucleus

Fornix

Lateral ventricle

Subcallosal area

Diagonal band of Broca (vertical limb) Tenia tecta (ventral)

Accumbent neuroepithelium (intermingled with the rostral migratory stream)

PREOPTIC AREA

Median preoptic nucleus Medial preoptic nucleus


HYPOTHALAMUS

Interpeduncular nucleus?

Oculomotor nuclear complex Dorsal tegmental nucleus?

Third ventricle




Lingula Centralis Culmen (I-II) (III) (IV-V)

Cerebral aqueduct

Diencephalic (hypothalamic) glioepithelium/ ependyma

Ansa lenticularis?


MIDBRAIN

Central gray

Lateral preoptic and hypothalamic areas l dia Me brain fore ndle? bu

Primary fissure

TECTUM

Su pe b nu tha cle lam us ic

mm r co



t rac

Inferior colliculus

Nucleus accumbens

Corpu sc (rostr allosum um )

O p ti c

e r io

Ant

Caudate (head)


TEGMENTUM

Inte rn (An al ca terio psu r lim le? b)

GABASA NG L LI A

psule al ca n r e t Ex

Stria terminalis Basal nucleus of Meynert?

SU IN B S T NO A M I NTI NA A Ce reb TA ra l

str

en

au Cl


Ventral striatum

um m

ru

Pu

In

a su l

y rg

ta

Frontal lobe

Temporal lobe

Declive (VI)

Folium (VIIa)

CEREBELLAR VERMIS

Central nucleus

Subgranular External germinal zone layer Brachium of the inferior colliculus

Subgranular zone Subgranular zone



Subiculum Dentate gyrus

CEREBELLAR HEMISPHERE Primary fissure

Ammon's horn

Glioepithelium Stria terminalis


Frontal stratified transitional field Frontal neuroepithelium and subventricular zone

Lateral migratory stream Posterior striatal neuroepithelium and subventricular zone


Subpial granular layer (infiltrating the claustrum and entering the insular cortex and temporal cortex)

White matter



348



349

PLATE 235B Primary olfactory cortex (piriform)

Internal capsule? (posterior limb)

Lateral fissure

Caudate? (tail)

Orbital gyrus



Temporal lobe

Temporal lobe


Choroid plexus

Frontal lobe

HIPPOCAMPUS (DORSAL)

Central nucleus TA NT IA IN NO MI NA TA

Endopiriform nucleus Anterior commissure Basal nucleus of Meynert

Fimbria/fornix

Basolateral complex


Intercalated mass?

Islands of Calleja Diagonal band of Broca (vertical limb) Medial preoptic nucleus


Median preoptic nucleus Tenia tecta (ventral)

C

SU

BS

Corticomedial complex Amygdalohippocampal O area? traptic ct Ansa Parabrachial lenticularis? nucleus Me

Oculomotor nerve (III) Medial longitudinal fasciculus Oculomotor nuclear complex Dorsal tegmental nucleus? Central gray


d ia

Lateral preoptic and l forebr ? Red a i n b u n dl e hypothalamic areas Mammillo- nucleus Fornix thalamic tract SupraDorsomedial mammillary nucleus? area Interpeduncular PREOPTIC nucleus Third ventricle AREA HabenuloParaventricular HYPOinterpeduncular nucleus THALAMUS tract

y tor fac cle Ol uber t


nigra

Diencephalic (hypothalamic) glioepithelium/ ependyma

AMYGDALA

Cerebral aqueduct

MIDBRAIN TECTUM Inferior colliculus

Subcallosal area

Fornical glioepithelium MIDBR AIN T Lateral lemniscus e l c n G edu p M Nucleus of the lateral l EN ra lemniscus (dorsal) TU eb Substantia r M e

Primary fissure

E

N accuucleus mbe ns


Lateral ventricle

Mesencephalic glioepithelium/ ependyma Central nucleus Myelination gliosis Reticular formation Brachium of the inferior colliculus

HI P (V P O C EN A TR M P AL US )

S

ub

gr

u an

la

e on z r

An

io ter

ob

rl

e(

-H HI

ule lob lex I) p Sim (HV


V)



Declive (VI)

Folium (VIIa)

Tuber (VIIb)

CEREBELLAR VERMIS

CEREBELLAR HEMISPHERE


Subiculum Dentate gyrus Ammon's horn


Primary fissure



Parahippocampal stratified transitional field Layer I Layer II Layer III Layer IV Layers V-VI



(infiltrating the endopiriform nucleus and entering the piriform cortex, temporal cortex, and amygdala)

Amygdaloid glioepithelium/ ependyma Alvear glioepithelium

White matter


Cortical plate

350



351

PLATE 236B Germinal and transitional structures in italics Layer I


Lateral fissure

Anterior commissure

Layer II Layer III Cortical plate Layer IV Layers V-VI White matter

Temporal lobe

Lateral ventricle

Uncinate fasciculus

Orbital gyrus




PUS

Basolateral complex

AM

Intercalated masses


POC

Frontal lobe

HIP

Central nucleus?

Lateral lemniscus

Amygdalohippocampal area?

MIDBRA IN TE G e

ncl edu lp


ra eb er Substantia nigra Ventral tegmental C


Olfactory tubercle Mammillothalamic tract


Third ventricle (preoptic recess) Periventricular nucleus


Ventromedial nucleus PREOPTIC AREA

Sexually dimorphic nucleus?

Fornix

area

tor mo u lo I II ) Oc rve ( e n

Mammillary Interbody peduncular Myelination nucleus gliosis Diencephalic

(hypothalamic) glioepithelium/ ependyma HYPOTHALAMUS O tra ptic ct

AMYGDALA



NTU M

A

al ntr Ce ray g

r rio n te

lob

V) -H I H e(

D

Cerebral aqueduct

Reticular formation Medial longitudinal fasciculus Raphe nuclear complex


s

Paramedian lobule? (HVIIB)

Tuber (VIIb) Pyramis (VIII)

Folium (VIIa)

CEREBELLAR VERMIS

Dentate gyrus Subgranular zone Subiculum Dentate gyrus Ammon's horn


Amygdaloid glioepithelium/ependyma Alvear glioepithelium

ucleu



Subpial granular Subpial granularlayer layer

en en ta t


Interpo situs nu cleus


Supraoptic nucleus



Superior cerebellar peduncle Dorsal tegmental nucleus? Trochlear nucleus (IV) Superior cerebellar peduncle (decussation)

Subcallosal area

ME

ule lob x ) ple VI Sim (H

Primary fissure


CEREBELLAR DEEP NUCLEI

CEREBELLAR HEMISPHERE External germinal layer

352



353


White matter

Layer II Layer III Cortical plate Layer IV Layers V-VI Layer I

Temporal lobe


Lateral ventricle

Lateral fissure Endopiriform nucleus

Amygdalohippocampal area?

EG IN T MENT U RA cle M

Lateral tuberal nucleus Optic tract Ventromedial nucleus

Third ventricle (mammillary recess) Mammillary body

Suprachiasmatic nucleus Lamina terminalis Arcuate nucleus

InterOculomotor peduncular nerve (III) nucleus

HYPOTHALAMUS

Diencephalic Myelination gliosis (hypothalamic) glioepithelium/ ependyma

coeruleus Abducens nucleus (VI)

Raphe nuclear complex Medial longitudinal fasciculus

Infe

ri o

rc

e

un ped ar l l be re

D

PONTINE TEGMENTUM

cle

e nu e n ta t

cleus


le

Fourth ventricle Reticular formation

e(

V)


Fastigial nucleus

Uvula? (IX)


Pyramis (VIII)

CEREBELLAR VERMIS

BE


ob

l ior

-H HI

C E RE

Olfactory peduncle

Lateral lemniscus Nucleus of the lateral lemniscus (dorsal)

r edun n te lp A a Parabrachial br ia nucleus nt a s t s ra iscu ? b or cerebellar g ri ped Su ni lemn e Locus unc up Superior cerebellar peduncle (decussation)

Gyrus rectus

ule ob l x ) ple VI Sim (H

Primary fissure

Ce MID B re

Co r ti comcome p le d ia l x

S


l

Frontal lobe


M ed ia

Basolateral complex


MPUS HIPPOCA

Orbital gyrus


LL

Alvear glioepithelium Ammon's horn Entorhinal cortex



Damaged area


Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal stratified transitional field Temporal neuroepithelium and subventricular zone

AR


AMYGDALA


Subgranular zone Dentate gyrus Subiculum

D

EE

PN

UC

LE I



354



355


White matter Layer II Layer III Cortical plate Layer IV Layers V-VI


Layer I

AM ALA YGD

Frontal lobe

Basolateral complex Oculomotor nerve (III)

ncle edu lp

PONS

Parabrachial nucleus Locus coeruleus

ior

D r ll a

Fourth ventricle

oid plex


p llar ebe r e c


le unc ed

e nu e n ta t

cleus

pe

du

n


Nodulus Uvula (X) (IX)


Pyramis (VIII)

CEREBELLAR VERMIS Germinal trigone

us

Medial longitudinal fasciculus Dorsal longitudinal fasciculus Reticular formation


er

S uperior cere b e


Myelination gliosis

f In

hor

HYPOTHALAMUS Pontine (fragmented infundibular recess gray of the third ventricle surrounded by the arcuate nucleus) Medial lemniscus? Superior cerebellar peduncle


Optic chiasm

Olfactory peduncle

e ob rl ) o i V r te I-H An (H

Lateral lemniscus Transpontine corticofugal tract

Cereb ra

Anterior olfactory nucleus?

Orbital gyrus


e


(entering the amygdala and temporal cortex)

Primary fissure


cl

Lateral fissure

Gyrus rectus

Damaged area

Si m p (H lex VI lob ) ule

Damaged area

C





hinal corte tor x En

n

or

Damaged area

sh


A m m on'


Subic

ulum

Parahippocampal neuroepithelium, subventricular zone, and stratified transitional field Temporal neuroepithelium and subventricular zone Temporal stratified transitional field

CEREBELLAR DEEP NUCLEI



356



357


Temporal neuroepithelium, subventricular zone, and stratified transitional field? Inferior temporal gyrus


Layer I Layer II (stellate cell islands) Layer III Layer IV (lamina dessicans) Layers V-VI

Amygdaloid glioepithelium/ependyma?

Entorhinal stratified transitional field

Entorhinal cortical plate

Si m p (H lex VI lob ) ule


e ob rl ) o i V r te I-H An (H


ar ell b e cer le le nc dd edu i M p lar rebel or ce cle i r e f In pedun Dentate nucleus

Paramedian lobule? (HVIIB) Fourth ventricle

Lateral lemniscus?

Olfactory peduncle

Medial lemniscus?

(lateral recess) Floccular peduncle

Principal sensory nucleus? (V)


PONS Retic

HYPOTHALAMUS (infundibular recess of the third ventricle surrounded by the arcuate nucleus)



Damaged area

Fourth ventricle


Pontine gray

Spinal nucleus (V)

Nucleus of the lateral lemniscus? (ventral)

Paraflocculus (HIX)

Choroid plexus


Nodulus (X)

Prepositus nucleus

Nerve VII?

orhina Ent lc or te x

hinal corte tor x En

Entorhinal stratified transitional field

MEDULLA


Reticular formation


leus ular tegmental nuc

Pontocerebellar fibers (thin transverse bundles) Optic nerve


CEREBELLAR VERMIS

Medullary glioepithelium/ependyma Vestibular nuclear complex

Motor nucleus (V)

Germinal trigone

(continuous with the germinal source of the choroid plexus)

Choroid plexus

Spinal tract(V)



Primary fissure

Uvula (IX)



358



359

PLATE 240B Germinal and transitional structures in italics Ansiform lobule (Crus I HVIIA) (damaged) Ansiform lobule (Crus II HVIIA)

le bu x lo ) e l I p V Sim (H

e ncl edu p r ella reb e c e ddl Flocculus Mi

Anterior lobe? (HI-HV)

(HX)

Nerve V (myelination gliosis in root)



PONS

R fo etic rm u at lar ion


Nerve V? Nerve VII?

MEDULLA

Trapezoid body and medial lemniscus


R e tic u

Pontine gray


Medial longitudinal fasciculus?

Nerve VI? (myelination gliosis)


Nerve VII? (myelination gliosis)

Fourth ventricle

Raphe nuclear complex Prepositus nucleus

Reticular formation

lar tegm ental nucleus




Cuneate fasciculus Cuneate nucleus

SPINAL CORD

Gracile fasciculus


Gracile nucleus


Gracile fasciculus Central canal



Myelination gliosis (dorsal funiculus)

Spinal nucleus and tract? (V)

Germinal trigone (continuous with the germinal source of the choroid plexus)

Nerve V (myelination gliosis in root)

Choroid plexus Floccular peduncle

Ventral cochlear nucleus Dorsal cochlear nucleus

External germinal layer (dorsal cochlear nucleus) Glioepithelium (middle cerebellar peduncle)

CEREBELLAR HEMISPHERE External germinal layer

Cuneate fasciculus

360



361

PLATE 241B Germinal and transitional structures in italics Ansiform lobule (Crus I HVIIA) (damaged)


Floccular peduncle Fourth ventricle (lateral recess) Ventral cochlear nucleus


Flocculus (HX)


Middle cerebellar peduncle Nerve V (myelination gliosis in root)


PONS


Motor nucleus Ner ve V (VII) II l nd a y dina bod cus gitu n d o i l s o l pez mni Media lus? Tra dial le icu fasc Prepositus me nucleus

SPINAL CORD

MEDULLA

Raphe nuclear complex Nerve VI?

Hypoglossal nucleus? (XII) Reticular formation


S pi n and al nucl t r a c eu s t (V )

Reticular formation

r tegm ental nuc l e u s R et i c u l a


r olive Superioplex com

Pontine gray





Nerves VII and VIII?


Gracile fasciculus


Cuneate nucleus

Spi

I

Lissauer's tract

Area postrema

Fourth ventricle

cleus ) al nu Spin tract (V le and d unc lar pe l e b e r cer nferio


Cuneate nucleus

no


Choroid plexus

Glioepithelium (middle cerebellar peduncle)

Germinal trigone (continuous with the germinal source of the choroid plexus)

Central canal

s act r tr a l l ebe cer




iculus Cuneate fasc


Myelination gliosis (lateral funiculus)

362



363



Fourth ventricle (lateral recess) Glioepithelium (middle cerebellar peduncle)

Flocculus (HX)

Dorsal and ventral cochlear nuclei

Choroid plexus i or

r

Cun bella nuc eate r pe d uncl e leus Spin Cun and al nucl e e a t u r t act e nu Motor (V ) s cleu nucleus s (VII) So lita ry nu Dorsal sensory nucleus? (X) c le us Dorsal motor nucleus? (X) cere

Dorsal and ventral cochlear nuclei Germinal trigone (continuous with the germinal source of the choroid plexus)

fas

t

e

Reticular formation

Nerves VII and VIII?

rac

cil

Trapezoid body and medial lemniscus

Su pe comrior o ple live x


dt

Gracile nucleus?

c ic u

C une

lu s


a t e fa


s cicu


Spina and t l nucleus ract (V)


S p in

a S p in

l nuc

Choroid plexus


le u s

cts r t ra b e ll a e r e noc

(V )

Spi

Central canal Intraspinal tracts (intermingled with the medial longitudinal fasciculus and tectospinal tract)

lu s


Medial longitudinal fasciculus?

Motor nucleus (VII)

an

Fourth ventricle


Nerve VI?


SPINAL CORD

MEDULLA

Hypoglossal nucleus? (XII)


Lissauer's tract?

G ra

Transpontine corticofugal tract (thick longitudinal bundles) Pontocerebellar fibers (decussation)

e liv ro rio ex pe pl Su com

Pontine gray


In f e


PONS


al nu

(V ) c le u s


Myelination gliosis (lateral funiculus)


Ventral white commissure Myelination gliosis (ventral funiculus)

Spinocephalic (spinothalamic) tracts

364


See the entire section in Plate 229 (middle).

365

PLATE 243B Germinal and transitional structures in italics CEREBELLAR HEMISPHERE Fourth ventricle (lateral recess, torn) Ventral cochlear nucleus


Flocculus (HX) Choroid plexus Spinocerebellar tracts

Middle cerebellar peduncle Transpontine corticofugal tract (thick longitudinal bundles)

SPINAL CORD

PONS Reticular formation

MEDULLA

Reticular formation

Hypoglossal nucleus? (XII)



Pontine gray




Reticular formation

Choroid plexus



ts trac llar e b re oce pin

Ventral corticospinal tract Ventral white commissure

Medial longitudinal fasciculus and tectospinal tracts?

S

Raphe migration (penetrating the medullary arcuate nucleus)

Lateral corticospinal tract Intraspinal tracts (intermingled with the medial longitudinal fasciculus and tectospinal tract)


Myelination gliosis (ventral funiculus) Spinocephalic (spinothalamic) tracts Myelination gliosis (lateral funiculus)

366



367


Choroid plexus Ventral cochlear nucleus? Fourth ventricle (lateral recess, torn) Corticospinal tract (forming pyramid)


Spinoc e

SPINAL CORD

rebella r tracts

MEDULLA

PONS Pontine gray

Reticular formation

Medial lemniscus

Arcuate nucleus


Ventral white commissure





Pontocerebellar fibers (thin transverse bundles) Pyramid



Reticular formation

Spinocerebellar tracts Raphe migration (penetrating the medullary arcuate nucleus)

Intraspinal tracts (intermingled with the medial longitudinal fasciculus and tectospinal tract)

Medial longitudinal fasciculus? (an island of axons with reduced premyelinating glia) Spinocephalic (spinothalamic) tracts? Myelination gliosis (ventral funiculus)

368

GLOSSARY GLOSSARY An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. A Abducens nucleus (VI) – An aggregate of cranial nerve motor neurons situated beneath the *fourth ventricle in the *pons. The nucleus receives input from the *vestibular nuclear complex and is the source of motor fibers of cranial *nerve VI that innervate the lateral rectus muscle of the eye. Accessory basal nucleus – See Basal accessory nucleus. Accessory nucleus (XI) – A column of motoneurons that extends from the region of the *nucleus ambiguus in the medulla to the 5th-6th segments of the cervical spinal cord. Its axons form *nerve XI that innervates the sternocleidomastoid and trapezius muscles. Accumbent neuroepithelium – Putative germinal source of the neurons and neuroglia of the *nucleus accumbens. After cessation of neurogenesis, this germinal matrix is transformed into a *glioepithelium. Allocortex – Cortical regions of the telencephalon with a “threelayered” cytoarchitectonic organization, such as the *hippocampus and *primary olfactory cortex. At most hippocampal sites, a central layer of densely packed neurons is sandwiched between an external and internal fibrous layer with scattered neurons. The allocortex is a phylogenetically older telencephalic system than the mammalian “sixlayered” isocortex, or *neocortex. Alvear glioepithelium – Putative source of the glia of the *alveus (alveolar path) of the *hippocampus. Alveus – Deep layer of white matter that borders *Ammon’s horn region of the hippocampus. Ammon’s horn (hippocampus) – Part of the *hippocampus that contains a prominent layer of large pyramidal cells that curves toward the *dentate gyrus. Layers distinguished in Ammon’s horn are (from deep to superficial) the alveus, the stratum oriens, the pyramidal layer, the stratum radiatum, and the stratum lacunosum moleculare. Ammon’s horn is subdivided into two large areas: CA1 adjacent to the

*presubiculum, and CA3 adjacent to the *dentate gyrus. The two smaller regions are CA2 and CA4 (in the *hilus of the dentate gyrus). Amygdala – A large structure in the *uncus of the temporal lobe that is a basal ganglionic component of the limbic system. The complex cell groupings in the amygdala have been put into two major subdivisions: the *corticomedial complex and the *basolateral complex. This structure is involved in linking emotions with olfactory, auditory, and visual sensory information and plays a major role in behavioral aggression. Amygdalohippocampal area – Also called the cortical amygdaloid transition area, an ellipitical mass of densely packed cells in the caudomedial amygdala between the ventral *subiculum and the *cortical nucleus. It is connected to the *bed nucleus of the stria terminalis and the *ventromedial hypothalamic nucleus. Ansa lenticularis – Fiber tract that originates in the internal (medial) segment of the *globus pallidus, courses dorsal to the *zona incerta in *Forel’s fields, and terminates in the *thalamus, in particular the *ventral complex and the *centromedian nucleus. Anterior amygdaloid area – A region of small to medium-sized cells in the rostral half of the *amygdala that represents a transition zone between the *substantia innominata and the amygdaloid complex proper. Anterior commissure – Large fiber bundle that crosses in the ventral telencephalon and interconnects several forebrain structures on the right and left sides, including the *olfactory bulb, the *primary olfactory cortex, the *entorhinal area, the *amygdala, and some components of the *temporal lobe. Anterior complex (thalamus) – A group of anterior thalamic nuclei with related connections. Components of the anterior thalamic complex are the anterodorsal nucleus, the anteromedial nucleus, and the anteroventral nucleus. The afferents of the anterior complex come principally from the *hip-

pocampal region and the *mammillary body. The ascending efferents terminate in the *cingulate gyrus while the descending efferents terminate in the *mammillary body. The anterior thalamic complex is considered a component of the “limbic system”. Anterior cortical nucleus (amygdala) – The anterior part of the large *cortical nucleus that has less dense cellular accumulation in layer II. Anterior corticospinal tract – See Ventral corticospinal tract. Anterior lobe (cerebellum) – Region of the vermis and hemispheres in front of the primary fissure. It contains the *lingula, *centralis and *culmen in the vermis, and their extensions in the hemispheres. Anterior olfactory nucleus – A nucleus in the olfactory peduncle that has numerous anatomical connections to the *olfactory bulb and *primary olfactory cortex. Aqueduct – Narrow region of the ventricular system situated between the *third ventricle rostrally and the *fourth ventricle caudally. Aqueduct (embryonic) – During early development, the *neuroepithelium lining the hypertrophied aqueduct of the mesencephalon is the source of neurons and neuroglia of the *superior colliculus, the *inferior colliculus, the *central gray, the *tegmentum, and several components of the *isthmus. Arcuate nucleus (hypothalamus) – A small-celled nucleus that surrounds the base of the third ventricle posteriorly. It contains releasing hormones and is involved in the central nervous regulation of the anterior pituitary gland. Arcuate nucleus (medulla) –A small group of neurons in the ventral part of the *pyramids caudal to the *pontine gray. The chief afferents to this nucleus are from motor areas in the cerebral cortex. This nucleus provides output to the cerebellum. See also Raphe migration.

369 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. Area postrema – A circumventricular organ forming a dorsal eminence in the *fourth ventricle of the *medulla. It has connections with the hypothalamic *paraventricular nucleus, the *parabrachial nucleus of the pons and the *solitary nucleus of the medulla. It plays a role in the neuroendocrine regulation of feeding and drinking.

Basal nucleus of Meynert – Large-celled component of the *substantia innominata that provides cholinergic input to the *cerebral cortex.

Auditory radiation – Thalamocortical fibers in the internal capsule and cortical white matter that originate in the *medial geniculate body and terminate in the auditory cortex (transverse gyrus of Heschl) in the *temporal lobe.

Basal telencephalon – A general term sometimes used to refer to such *allocortical components of the telencephalon as the *primary olfactory cortex, and such noncortical regions as the *substantia innominata.

B

Basolateral complex – The largest and best differentiated part of the amygdala in man. It contains the *lateral nucleus, *basal nucleus, and *basal accessory nucleus.

Basal accessory nucleus (amygdala) – Also called the basomedial nucleus. This part of the *basolateral complex is located between the deep part of the *cortical nucleus and the large *basal nucleus. It contains small to medium-sized cells and some large cholinergic neurons. It is reciprocally connected to the *basal nucleus of Meynert, the rostral *temporal cortex, the prefrontal cortex, and the *orbital cortex; additional input comes from the *posterior complex of the thalamus. Its axons also terminate in the anterior *cingulate cortex, *insular cortex, *entorhinal cortex, *Ammon’s horn of the hippocampus, *nucleus accumbens, *dorsomedial nucleus of the thalamus, and *ventromedial nucleus of the hypothalamus. Basal ganglia – A broad term that includes three large ganglionic (subcortical) components of the telencephalon, the *caudate nucleus, the *putamen, and the *globus pallidus. The latter two are also referred to as the *striatum. The basal ganglia have been implicated in the coordination motor functions, and their diseases have been linked to Parkinsonism, Huntington’s disease, and other motor abnormalities. The *substantia nigra and the *subthalamic nucleus are part of the basal ganglia circuitry. Basal nucleus (amygdala) – The largest nucleus in the amygdala that forms a major part of the *basolateral complex. It is separated from the *lateral nucleus by a thin fibrous band. It contains small to medium-sized cells and many large cholinergic neurons. It is reciprocally connected to the *basal nucleus of Meynert, the cortex in the*temporal lobe, the *subiculum, and CA1 in *Ammon’s horn. Additional input comes from the cortex in the *parahippocampal gyrus. Its axons also terminate in the cortex of the *occipital lobe, medial *frontal lobe, *insular gyrus, and anterior *cingulate gyrus. Additional projections are to the *bed nucleus of the stria terminalis, *nucleus accumbens,

*striatum, *dorsomedial nucleus of the thalamus, and *lateral tuberal nucleus of the hypothalamus.

Bed nucleus of the stria terminalis – A large subcortical telencephalic field with indistinct boundaries. It is situated medial to the *globus pallidus, lateral to the *septum, and is transected by the *anterior commissure; a thin portion extends back to the *amygdala adjacent to the *stria terminalis. It has its own germinal source, the *strionuclear neuroepithelium and glioepithelium. Only the glioepithelium is present during the third trimester. It receives major input from the *amygdala. Biventral lobule (cerebellum HVIII) – A posterior and inferior hemispheric lobule, and a lateral extension of the vermal *pyramis. See also Cerebellum (Hemisphere). Brachium of the inferior colliculus – A fiber tract situated superficially in the fibrous covering of the *inferior colliculus. It is composed of ascending auditory fibers from the inferior colliculus and auditory nuclei in the *pons to the *medial geniculate body.

C

GLOSSARY

axons across the midline and have been postulated to provide mechanical scaffolding. It has recently been discovered that these cells are neurons and not glia (Shu, T., Y. Li, A. Keller, and L. J. Richards, 2003, Development, 130:2929-2937). Caudate nucleus – Elongated and arched component of the *basal ganglia beneath the *cerebral cortex. It abuts the lateral ventricle and extends from anterodorsal (its “head”) to posteroventral (its “tail”). Cave of the septum – Midline, membrane-bound triangular space beneath the *corpus callosum and above the *septum. Unlike the cerebrospinal *ventricles, it is without an ependymal lining. Central autonomic area (spinal cord) – Region of the spinal cord that surrounds the *central canal and is implicated in nociceptive and autonomic functions. It may be continuous rostrally with the periaqueductal *central gray. Central canal – Portion of the ventricular system that extends caudally from the medullary *fourth ventricle to the sacral segments of the *spinal cord. During embryonic development, the proliferative *neuroepithelium lining this canal is the source of neurons and neuroglia of the spinal cord. After the cessation of neurogenesis and gliogenesis the shrunken central canal is lined by the *ependyma. Central complex (thalamus) – A group of contiguous central thalamic nuclei, including the *centromedian, central lateral, and *paracentral nuclei. Central gray (periaqueductal) – Oval shaped region in the core of the mesencephalon that surrounds the *aqueduct and is capped by the *superior colliculus and the *inferior colliculus.

Callosal glioepithelium – Proliferative germinal matrix that lines the *corpus callosum in the fetal *cerebral cortex. It is the putative source of the myelinating oligodendroglia of the *corpus callosum.

Central lobe (cerebellum VI-VIII) – The vermal lobe that contains the latest maturing regions of the cerebellar cortex. It includes the *declive, *folium, *tuber, and *pyramis. It is separated from the *anterior lobe by the *primary fissure and from the *posterior lobe by the *posterolateral fissure. The lateral extension of the central lobe forms the main bulk of the hemisphere, including *crus I and *crus II of the ansiform lobule, *the biventral lobule, the *paramedian lobule, and the *simplex lobule.

Callosal sling – (formerly called glial sling) A thin layer of cells in the midline beneath the corpus callosum. During early development these cells precede the crossing of callosal

Central nucleus (amygdala) – Part of the *corticomedial complex that is sometimes put in a class by itself. A large nucleus positioned lateral to the *medial nucleus that extends from

Calcarine sulcus – Cortical fissure that extends from the *parietooccipital sulcus anteriorly to the occipital pole posteriorly. Along its wall is located the primary visual projection area, the *striate cortex.

370

GLOSSARY

An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined.

the *anterior amygdaloid area to the caudal pole of the amygdala where it blends with the *putamen and the tail of the *caudate nucleus. Its major inputs are from the hypothalamic *ventromedial nucleus, *lateral hypothalamic area, *substantia nigra, *ventral tegmental area, *parabrachial nucleus, and *posterior complex of the thalamus. It projects to the *lateral hypothalamic area, midline thalamus, and a wide array of brainstem targets, including the *central gray, *reticular formation (midbrain, pons, medulla), *substantia nigra, *solitary nuclear complex, and *dorsal motor nucleus (X). Central nucleus (inferior colliculus) – Laminated core of the *inferior colliculus where auditory fibers of the *lateral lemniscus terminate in a tonotopic order. Central sulcus – Large vertically oriented neocortical fissure between the *precentral gyrus and the *postcentral gyrus in the *paracentral lobule. The central sulcus divides the motor cortex (precentral gyrus) from the somatosensory cortex (postcentral gyrus). Central tegmental tract – Large fiber bundle with heterogeneous composition that extends from the *red nucleus in the midbrain to the *inferior olive in the medulla. Centralis (cerebellum III) –The middle lobule in the anterior lobe of the cerebellar vermis between the *lingula and the *culmen. Its posterodorsal border is defined by the *preculminate fissure. See also Cerebellum (Vermis). Centromedian nucleus (thalamus) – Large spherical structure surrounded by fibers of the internal medullary lamina, classified with the *central complex of the thalamus. It is a paleothalamic structure that has extensive connections with the *striatum and the midbrain *reticular formation. Cerebellar cortex – The highly convoluted and laminated outer shell of the cerebellum. It is composed of five layers, the superficial *external germinal layer (embryonic), the *molecular layer, the *Purkinje cell layer, the *granular layer, and the deep fibrous *medullary layer. The Purkinje cells originate in the cerebellar *neuroepithelium of the fourth ventricle, whereas the basket and stellate cells of the molecular layer, and the granule cells of the granular layer originate in the external germinal layer. The medullary layer contains the afferents and efferents of the cerebellar cortex. Cerebellar glioepithelium – Situated beneath the *superior cerebellar peduncle in the roof of the *fourth ventricle, this is

a remnant of the cerebellar neuroepithelium that is present during earlier stages of brain development. It is possibly the source of glia of some of the cerebellar peduncles and the white matter of the *medullary layer. Cerebellum (deep nuclei) – Three pairs of ganglionic structures in the depth of the cerebellum: the *fastigial nucleus (medial nucleus); the *interpositus nucleus (globose and emboliform, or intermediate nuclei); and the *dentate nucleus (lateral nucleus). The efferent fibers of cerebellar *Purkinje cells synapse with the neurons of the cerebellar deep nuclei which, in turn, are the source of cerebellofugal fibers that terminate in structures outside the cerebellum. Cerebellum (hemisphere) – Portion of the cerebellar cortex situated on either side of the midline vermis. Its principal components are the *simplex lobule, *crus I and II of the ansiform lobule, the *flocculus, and the *paraflocculus. Cerebellum (vermis) – Midline portion of the cerebellar cortex. It is divided by large fissures into 4 lobes with a total of 10 lobules: *anterior lobe (I-V), *central lobe (VI-VIII), *posterior lobe (IX), and *inferior lobe (X). Cerebral aqueduct – See Aqueduct. Cerebral cortex – The largest structure in the human brain that is composed of a cell sparse *layer I and cellular layers (II-VI) that vary in composition in specific regions of the *neocortex or *allocortex. The neocortex is subdivided into frontal, parietal, occipital, and temporal lobes, and the paracentral lobule. The primordium of cortical layers II-VI is the *cortical plate. Cerebral peduncle – Fiber mass along the ventrolateral aspect of the diencephalon and mesencephalon. The term refers to fibers of the *corticofugal tract between the *internal capsule rostrally and the *transpontine corticofugal tract caudally. Choroid plexus – Highly vascularized and arborized epithelial tissue of mesenchymal origin that secretes the cerebrospinal fluid circulating in the brain ventricles and subarachnoid spaces of the meninges. The *lateral, *third, and *fourth ventricles have their own choroid plexus arbors. Cingulate gyrus – Medial *allocortical region that extends rostrocaudally above the corpus callosum. Its principal afferent connections are with nuclei of the thalamic *anterior complex, and its efferents target the *hippocampal region, the

*septum, the *amygdala, and the *frontal lobe. It is considered a component of the “limbic system.” Cingulate neuroepithelium – Putative source of the neurons and glia of the cingulate gyrus. It is flanked by the cingulate *subventricular zone and *stratified transitional field before the sojourning and migrating neurons settle in the cortical plate. Cingulum – Large longitudinal fiber bundle situated above the *corpus callosum that follows the contours of the *cingulate gyrus. It contains efferents of the cingulate gyrus and long association fibers that interconnect it with the *hippocampal region and the *frontal lobe. Claustrum – Subcortical gray matter adjacent to the *insula and separated from it and the *striatum by two fibrous layers, the extreme capsule and the *external capsule. There is some evidence that the claustrum is reciprocally connected with the *neocortex. During embryonic development it is in the path of the *lateral migratory stream. Cochlear nucleus (dorsal) – This auditory nucleus occupies the external surface of the *inferior cerebellar peduncle and forms an eminence in the lateral part of the *fourth ventricle floor. Its neurons get input from primary auditory neurons in the cochlear spiral ganglion, which form the auditory component of cranial *nerve VIII. The dorsal cochlear nucleus sends ipsilateral and contralateral axons to the *lateral lemniscus that terminate in the *nuclei of the lateral lemniscus, the *inferior colliculus, and the *medial geniculate body. Cochlear nucleus (ventral) – This nucleus surrounds the lateral and ventral parts of the *inferior cerebellar peduncle. Its neurons get input from primary auditory neurons in the spiral ganglion. Axons of this nucleus cross the midline in the *trapezoid body and terminate in the contralateral *nuclei of the lateral lemniscus, the *inferior colliculus, and the *medial geniculate body. Commissural nucleus (X) – A small nucleus that is part of the sensory nuclei associated with the vagus nerve and the solitary complex. It lies caudal to the obex in the medulla where the *solitary nuclei on both sides of the brain are joined. See also Nerve X. Corona radiata – Fan-shaped radiating mass of ascending (thalamocortical) and descending (corticofugal) fibers of the *internal capsule. It is continuous with the *white matter of the *cerebral cortex.

371 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. Corpus callosum – Large commissural fiber system that interconnects the two halves of the cerebral hemispheres. The frontal part of the corpus callosum, the genu, interconnects the anterior part of the frontal lobes. Its “body” interconnects the posterior *frontal lobe, the *paracentral lobule, and the *parietal lobe. The splenium contains the commissural fibers of the *temporal lobe and the *occipital lobe. Cortical nucleus (amygdala) – Also called the periamygdaloid cortex, part of the *corticomedial complex in the superficial amygdala adjacent to the *medial nucleus. It is characterized by a cell-sparse layer I, a dense layer II, and a scattered layer III. It gets input from the *olfactory bulb, *primary olfactory cortex, CA1 in *Ammon’s horn, and the *subiculum. It projects to the olfactory bulb, CA1, the *orbital gyrus, and the *dorsomedial nucleus of the thalamus. Cortical plate – The densely packed cells of layers II-VI in the embryonic and fetal *cerebral cortex. It is situated between the preplate (the future molecular layer, or *layer I) and the subplate (the future layer VII). Corticomedial complex (amygdala) – The part of the *amygdala that includes the *anterior amygdaloid complex, the *cortical nuclei, the *nucleus of the lateral olfactory tract, the *medial nucleus, and the *central nucleus. Corticofugal tract – Collective term for the efferent fiber system that originates in the cerebral cortex and terminates in subcortical structures. It is known by different names as it passes from rostral to caudal: *internal capsule, *cerebral peduncle, *transpontine corticofugal tract, *pyramid, *pyramidal decussation, and *corticospinal tract. Corticospinal tract – Component of the *corticofugal tract that targets the spinal cord. The bulk of the corticospinal fibers cross in the *pyramid of the medulla and descend from cervical to sacral levels in the *lateral corticospinal tract. A smaller component descends ipsilaterally in the *ventral corticospinal tract. Crus I, ansiform lobule (cerebellum HVIIA) – The large anterior part of the ansiform lobule. It is a lateral extension of the *folium in the vermis. Crus II, ansiform lobule (cerebellum HVIIA) – The smaller posterior part of the ansiform lobule that is a lateral extension of the *tuber in the vermis.

Culmen (cerebellum IV-V) – The largest lobule in the *anterior lobe of the cerebellar *vermis. It is separated from the *centralis by the *preculminate fissure and from the *declive in the *central lobe by the *primary fissure. The anterior lobe in the cerebellar hemispheres is mainly a lateral extension of the culmen. Cuneate fasciculus – A large fiber tract in the dorsolateral spinal cord and caudal medulla. It is composed of primary sensory fibers of dorsal root ganglion cells that terminate topographically in the *cuneate nucleus. Nissl-stained sections of this fiber tract show prominent *myelination gliosis during the early third trimester. Cuneate nucleus – Neurons that invade the *cuneate fasciculus from the ventral aspect to form a large mass in the posterolateral *medulla. Its chief input is from the *cuneate fasciculus and its output fibers cross the midline and enter the contralateral *medial lemniscus. Cuneus – Wedge-shaped region of the medial *occipital lobe situated above the *calcarine sulcus and behind the *parietooccipital sulcus.

D Declive (cerebellum VI) – The most anterior lobule of the vermal *central lobe. Its anterior border is defined by the *primary fissure. The declive is continuous with the *simplex lobule in the hemisphere. Dentate granular layer – See Granular layer (dentate gyrus). Dentate gyrus – Curved small-celled component of the *hippocampus, interlocked with the large-celled *Ammon’s horn. It has an outer *molecular layer, a discrete *granular layer, and a *hilus that contains the *subgranular zone, a secondary germinal matrix. Dentate nucleus (cerebellum) – Lobulated and largest of the *cerebellar deep nuclei, also known as the lateral cerebellar nucleus. Situated in the core of the cerebellar hemispheres, the dentate nucleus is the principal source of efferent fibers of the *superior cerebellar peduncle. Diagonal band of Broca – Oblique nucleus situated ventral to the medial *septum. It is subdivided into a vertical limb dorsally and a horizontal limb ventrally. Diencephalic neuroepithelium – The germinal matrix lining the embryonic *third ventricle. It is the source of neurons

GLOSSARY

and glia of all components of the diencephalon. Its different subdivisions produce cells for the different regions or nuclei of the *thalamus, *hypothalamus, and *preoptic area. Dorsal accessory olive – A dense band of neurons that arch over the principal nucleus in the *inferior olive of the *medulla. Its chief input is proprioceptive afferents from the *spinal cord, its efferents target the contralateral cerebellar *vermis, via the *inferior cerebellar peduncle. Dorsal complex (thalamus) – Collective term for two structurally and functionally related dorsally situated thalamic regions, the *dorsomedial nucleus and the dorsolateral nucleus. Dorsal gray matter (spinal cord) – Wing-shaped region of the spinal gray matter, the target of dorsal root afferents or their collaterals. Its principal component is the smallcelled substantia gelatinosa. The neurons of the dorsal gray matter originate in the *neuroepithelium flanking the transient dorsal spinal canal. Dorsal longitudinal fasciculus – A small fiber tract in the dorsomedial *medulla that extends to the ventromedial *central gray in the *midbrain. It relays visceral sensory and motor messages upstream and downstream between the medulla and the midbrain. Dorsal motor nucleus (X) – A column of parasympathetic preganglionic motor neurons dorsolateral to the *hypoglossal nucleus. Their axons leave the brain in cranial *nerve X and terminate in the intramural parasympathetic ganglia supplying the viscera of the thoracic, pericardial, and abdominal cavities. See also Nerve X. Dorsal sensory nucleus (X) – A medial nucleus in the *solitary nuclear complex of the *medulla that lies dorsolateral to the *dorsal motor nucleus (X) and is continuous with the *commissural nucleus (X). See also Nerve X. Dorsal tegmental nucleus – Situated in the central gray dorsal to the *trochlear nucleus and extending caudally into the pons. It is targeted by fibers of the *mammillotegmental tract. Dorsal white matter (spinal cord) – Medial fibrous component of the white matter situated between the wings of the *dorsal gray matter; also known as the dorsal column or the dorsal funiculus. It contains ascending somatosensory and proprioceptive fibers that terminate in the dorsal column nuclei of the medulla. In the upper spinal cord it has two distin-

372

GLOSSARY


guishable parts, the *gracile fasciculus medially, and the *cuneate fasciculus laterally. Dorsomedial nucleus (hypothalamus) – Area situated above the more distinct *ventromedial nucleus of the hypothalamus. Its principal connections are with the *bed nucleus of the stria terminalis and the *septum. Dorsomedial nucleus (thalamus) – Also known as the medial dorsal nucleus, this component of the *dorsal complex is situated between the internal medullary lamina and the periventricular gray, and has a large-celled and small-celled division. Its principal connections are with the *amygdala, the *hypothalamus, the *olfactory tubercle, and the *orbital gyrus. It is considered a paleothalamic component of the limbic system rather than as a neothalamic relay nucleus to the neocortex.

E Endopiriform nucleus – Small telencephalic nucleus deep to the *primary olfactory cortex and ventral to the *claustrum. The *lateral migratory stream percolates through this nucleus. Entorhinal cortex – Multilayered cortical component of the *parahippocampal gyrus. It is bordered internally by the *subicular complex and is separated from the *neocortex by the rhinal sulcus. It is the source of the perforant pathway to the *hippocampus. Ependyma – Layer of cuboidal cells that line the lumen of the permanent brain *ventricles and *central canal after dissolution of the proliferative *neuroepithelium. External capsule – Slender fiber band situated between the *claustrum and the *putamen. External cuneate nucleus – Situated lateral to the *cuneate nucleus in the *medulla, also known as the accessory cuneate nucleus, it is the source of the cuneocerebellar tract. The nucleus relays somesthetic and proprioceptive information from anterior regions of the body to the *cerebellum. External germinal layer (cerebellum) – Subpial, secondary germinal matrix of the cerebellar cortex, the source of its granule, stellate, and basket cells. It has two components, an outer proliferative zone and an inner premigratory zone. It persists as a source of neurons over the surface of the human cerebellar cortex until the end of the second year of postnatal life.

F

callosum and above the *thalamus, then turns downward and subdivides into a precommissural part that distributes fibers to the *septum, and a postcommissural part that curves behind the *anterior commissure. The postcommissural fibers traverse the diencephalon and most of them terminate in the nuclei of the thalamic *anterior complex and the *mammillary body.

Facial motor nucleus – A large aggregate of somatic motor neurons in the ventrolateral pons dorsal to the *superior olive complex. It is the source of the motor fibers of *nerve VII that innervate the facial mimetic muscles. Subdivisions of this nucleus innervate different facial muscles. Fasciola cinereum – Transitional region that wraps around the splenium of the *corpus callosum connecting a primordium of the hippocampal *dentate gyrus to the *induseum griseum. Fastigial nucleus (cerebellum) – A deep nucleus of the *cerebellum, also known as the medial cerebellar nucleus. It is the target of Purkinje cell axons that originate in the *vermis. Its axons contribute to the large efferent system that leaves the cerebellum. Fimbria – Large fiber tract of the *hippocampus that runs parallel with and then joins the *fornix. Floccular peduncle – Stalk in the cerebellum that connects the *flocculus with the *nodulus. The *germinal trigone is often strung out along the base of this peduncle. Flocculus (cerebellum) – Lateral extension of the vermal *nodulus in the *cerebellar hemisphere. The principal connections of the two, sometimes called the flocculonodular lobe, are with the vestibular system. Folium (cerebellum VIIa) – Component of the *central lobe, anterior to the *tuber. The hemispheric extension of the folium is *crus I of the ansiform lobule. Together with the *tuber, this is a late-maturing region of the cerebellar cortex. Foramen of Monro – Paired channels in the ventricular system that connect the *lateral ventricles in the telencephalon with the *third ventricle in the diencephalon. Forel’s fields – Subthalamic tegmental field (H1 and H2) with fiber bundles of the *ansa lenticularis, lenticular fasciculus, and subthalamic fasciculus. Fornical glioepithelium – Germinal matrix lining the fornix that persists for some time after the dissolution of the hippocampal neuroepithelium. It is the putative germinal source of the oligodendrocytes of the fornix. Fornix – The principal efferent fiber tract of the *hippocampus. The body of the fornix courses forward under the *corpus

Fourth ventricle – Region of the ventricular system in the *pons and *medulla between the *aqueduct rostrally and the *central canal caudally. Fourth ventricle (embryonic) – The neuroepithelium surrounding the hypertrophied fourth ventricle and its several recesses is the source of neurons and glia of the *medulla, the *pons and the *cerebellum. Many of the neurons migrate over long distances to their settling sites. Frontal lobe – Region of the cerebral cortex anterior to the *central sulcus. Some components of this region, e.g., *precentral gyrus and *orbital gyrus, are often excluded. Its major convolutions are the superior, middle and inferior frontal gyri. Minor convolutions are the gyrus rectus, the inferior rostral gyrus, and the superior rostral gyrus. Frontal neuroepithelium – Putative source of the neurons and glia of the *frontal lobe. Before settling in the cortical plate, its cells form the frontal *subventricular zone and *stratified transitional field.

G Germinal trigone (cerebellum) – Proliferative germinal matrix in the fourth ventricle beneath the *nodulus that contains three prongs: the *cerebellar neuroepithelium/glioepithelium, the *choroid plexus, and the *external germinal layer. Glial sling (corpus callosum) – See Callosal sling. Glioepithelium – Fate-restricted germinal matrix in the developing brain, the presumed source of neuroglia (astrocytes and oligodendroglia). Glioepithelia are easiest to recognize without special glial markers at sites of considerable distance from neuronal aggregates or their migratory routes, such as along the *corpus callosum, the *fornix, and the *stria terminalis. Globus pallidus – Component of the *striatum, situated medial to the *putamen, with an external (lateral) and internal (medial) segment. Pallidal fibers are the principal efferents

373 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. from the striatum to the *thalamus, the *subthalamus, and the *tegmentum. Gracile fasciculus – A prominent fiber tract in the dorsomedial spinal cord and the caudal medulla. It is composed of axons from dorsal root ganglia that convey sensory input from lower parts of the body. The fibers terminate topographically in the *gracile nucleus. Nissl-stained sections of this fiber tract show prominent *myelination gliosis during the early third trimester. Gracile nucleus – Gray mass in the core of the *gracile fasciculus that receives input from that fiber tract. Axons of these neurons cross the midline in the sensory decussation and enter the contralateral *medial lemniscus. The axons terminate topographically in the *ventral complex of the thalamus. Granular layer (cerebellar cortex) – Situated beneath the monolayer of large Purkinje cells, it is composed principally of small, densely packed neurons, the granule cells. The embryonic source of cerebellar granule cells is the *external germinal layer. The axons of granule cells, the parallel fibers, are distributed superficially in the *molecular layer of the cerebellar cortex. Granular layer (dentate gyrus) – Layer of the hippocampal *dentate gyrus with densely packed granule cells. The dendrites of granule cells are distributed in the *molecular layer, and their axons, the mossy fibers, synapse with the pyramidal cells of *Ammon’s horn. Most of the granule cells originate late in development (late second trimester, third trimester, and postnatally) in the *subgranular zone of just beneath the granular layer. Gray matter – General term for central nervous regions with a high concentration of neuronal cell bodies and unmyelinated nerve processes but few myelinated fibers. In fresh tissue, such regions appear gray. In histological preparations stained for neuronal cell bodies (perikarya) and their nuclei, the gray matter stands out against the *white matter by a high concentration of peikaryal profiles. In histological preparations that impregnate myelinated fibers, the gray matter appears pale against an opaque background.

H Habenular nuclei – Mediodorsally situated nuclei in the posterior *thalamus; sometimes distinguished from the thalamus proper as the epithalamus. There are two distinct habenular nuclei, the medial and the lateral. Habenular afferents

come principally from the *septum and the *hypothalamus, and its efferents form the *habenulo-interpeduncular tract.

chiasmatic nucleus, the *supraoptic nucleus, the *paraventricular nucleus, the *arcuate nucleus, the *ventromedial nucleus, the *dorsomedial nucleus, the *lateral tuberal nucleus, and the *mammillary body. The supraoptic, paraventricular, and arcuate nuclei produce and release neurohormones. The hypothalamus is considered the head ganglion of the autonomic nervous system and, by way of its neural and hormonal links with the pituitary gland, of the neuroendocrine system.

Habenulo-interpeduncular tract – A fiber bundle, also known as the fasciculus retroflexus, originating in the *habenular nuclei. It courses through the posterior *thalamus and terminates in the *interpeduncular nucleus of the midbrain. Hilus (dentate gyrus) – Deep layer in the the *dentate gyrus that forms a V-shaped hook around the tip of field CA4 of *Ammon’s horn; this layer contains large polymorph cells intermingled with small neurons. The *subgranular zone forms its superficial edge at the base of the *granular layer.

GLOSSARY

I Induseum griseum – Small, medially situated extension of the *hippocampus that lies above the *corpus callosum throughout its entire length.

Hippocampal neuroepithelium – Putative source of the neurons and glia of the hippocampus that is present early in development. During the third trimester the hippocampal neuroepithelium is presumably transformed into the *alvear glioepithelium. It lines the internal wall of the hippocampo-amygdaloid fork of the *lateral ventricles opposite the *amygdaloid neuroepithelium, the *striatal neuroepithelium and the *temporal neuroepithelium. Its three distinctive components are the source of the large neurons of *Ammon’s horn, the *subgranular zone that generates the smaller granule cells of the *dentate gyrus, and the *fornical glioepithelium.

Inferior cerebellar peduncle – Large fiber tract (also known as the restiform body). It contains ascending afferents to the cerebellum from the *spinal cord (spinocerebellar tracts), the *external cuneate nucleus, the *inferior olive, and the *lateral reticular nucleus.

Hippocampal region – An inclusive term (also called the hippocampal formation) that includes not only the *hippocampus proper but also the adjacent *subiculum, *presubiculum and *parasubiculum of the *parahippocampal gyrus.

Inferior lobe (cerebellum X) – A lobule in the *cerebellar vermis that is coextensive with the *nodulus. It is separated from the *posterior lobe by the posterolateral fissure. The *flocculus in the cerebellar hemisphere is a lateral extension of the nodulus, being connected to it by the floccular peduncle. The two are sometimes distinguished as the vestibulocerebellum.

Hippocampus – A distinctive allocortical (three-layered) region formed by the interlocking *dentate gyrus and *Ammon’s horn. The hippocampus is continuous with the *subicular complex. The principal afferents of the hippocampus travel in the alveolar and perforant paths; its efferents leave by way of the *fimbria that join the *fornix. Hypoglossal nucleus (XII) – A column of somatic motor neurons near the floor of the *fourth ventricle in the caudal medulla. Their axons form cranial *nerve XII that innervate the intrinsic and extrinsic muscles of the tongue. Hypothalamus – Large diencephalic system that surrounds the ventral (or hypothalamic) *third ventricle. It is continuous anteriorly with the *preoptic area and merges caudally with the midbrain *tegmentum. The hypothalamus contains a large number of discrete nuclei, among them the *supra-

Inferior colliculus – Paired inferior hillocks of the midbrain *tectum that receive primary, secondary, and higher order auditory afferents. The output of the inferior colliculus is mainly to the *medial geniculate body in the thalamus, but some axons extend to the primary auditory cortex in the *temporal lobe.

Inferior olive – A distinctive region in the ventrolateral *medulla above the *pyramids and an important component of the precerebellar system. It contains three nuclei. The large principal nucleus is a convoluted structure with a laminar organization that receives input from the *spinal cord, the *red nucleus, motor areas of the *cerebral cortex, and the *central gray. Its axons cross the midline and enter the contralateral *inferior cerebellar peduncle and terminate in the *cerebellar cortex as climbing fibers. The *dorsal accessory olive and the *medial accessory olive are small dense bands of neurons above and medial to the principal nucleus.

374

GLOSSARY


Inferior vestibular nucleus – This nucleus begins caudally in the *medulla near the *external cuneate nucleus and extends rostrally along the medial border of the *inferior cerebellar peduncle. Its neurons receive afferents from the vestibular ganglion and their efferents target the *nodulus and the *flocculus. Some axons also join the *medial longitudinal fasciculus and terminate in cranial motor nuclei (III, IV, VI) that control extraocular muscles.

Isthmal glioepithelium/ependyma – The putative source of glia and the site of proliferating ependymal cells in the *isthmus that lines the posterior *aqueduct. This structure replaces the isthmal neuroepithelium.

Infundibular recess – Small recess of the third ventricle that evaginates into the *infundibulum.

L

Infundibulum – Stalk extending from the mediobasal *hypothalamus that contains the median eminence and forms a link to the pituitary gland. Insula (insular cortex) – Large buried neocortical region behind the lateral fissure. Its components (gyri breves, gyri longus) are continuous internally with the *frontal, *parietal and *temporal lobes. Intercalated cell groups (amygdala) – Densely packed clusters of small cells that are typically embedded in the white matter between nuclei in the basolateral and corticomedial complexes in the *amygdala. Interhemispheric fissure – Longitudinal cleft that separates the two cerebral hemispheres. It is traversed by the *corpus callosum. Internal capsule – Massive fiber tract between the *thalamus and *striatum, composed of thalamocortical and corticofugal fibers. It is continuous with the *corona radiata rostrally, and the *cerebral peduncle caudally. Interpeduncular nucleus – Midline mesencephalic structure above the interpeduncular fossa and between the *cerebral peduncles. It is the target of fibers of the *habenulo-interpeduncular tract. Interpositus nucleus (cerebellum) – A deep cerebellar nucleus located between the *dentate nucleus and the *fastigial nucleus. It contains a lateral and a medial group of neurons, the emboliform near the *dentate nucleus, and the globosus near the *fastigial nucleus. Islands of Calleja – Scattered clusters of small granule cells within the *olfactory tubercle and along the medial border of the *nucleus accumbens.

Isthmus – Interconnecting bridge between the *midbrain and the *pons that is more prominent during earlier brain development than in the third trimester.

Lamina terminalis – Anterior membranous border of the *third ventricle. It is the site where the anterior neuropore closes during early embryonic development. Lateral corticospinal tract – A component of the larger *corticofugal tract that originates mainly from layer V in the motor area (including the large Betz pyramidal cells) and other areas of the cerebral cortex that controls skeletal muscles in the contralateral trunk and limbs. Axons carrying somatic motor output cross the midline in the *pyramidal decussation and descend through the entire length of the spinal cord in the dorsolateral part of the *lateral funiculus. Axons leave the tract in a topographically organized manner to terminate directly on spinal motoneurons in the ventral horn from cervical to sacral levels. Lateral fissure – Deep, oblique sulcus (also known as the Sylvian fissure) that separates the *frontal lobe and the *paracentral lobule anterodorsally from the *temporal lobe ventrally. Lateral funiculus (spinal cord) – Region of the spinal cord white matter that flanks the gray matter laterally. Major components of the lateral funiculus are the *lateral corticospinal tract, the *spinocephalic tract, and the *spinocerebellar tracts. Lateral geniculate body – Distinct thalamic region composed of the laminated dorsal lateral geniculate nucleus and its fiber capsule. The principal afferents of this visual relay structure are ipsi- and contralateral fibers of the *optic tract; the principal target of its efferents is the ipsilateral *striate cortex. The connections of the lateral geniculate nucleus and the striate cortex are reciprocal. Lateral hypothalamic area – An ill-defined fibrous region of the *hypothalamus with scattered neurons medial to the cerebral peduncle. It is traversed by many fiber tracts, including the *medial forebrain bundle. The region has been implicated in behavioral arousal and motivation.

Lateral lemniscus – The fiber tract on the lateral surface of the *pons that contains secondary auditory fibers from the dorsal and ventral *cochlear nuclei and higher-order auditory fibers from the *superior olivary complex. The dorsal and ventral *nuclei of the lateral lemniscus are embedded within the fiber tract. Lateral migratory stream (cortical) – Tangentially-migrating neurons and glia in the developing *cerebral cortex that leave dorsal parts of the neocortical *neuroepithelium and migrate laterally and ventrally to insular and temporal cortical areas and other telencephalic structures that lack a nearby germinal matrix. The bulk of the lateral migratory stream follows a trajectory outlined by the receding *subventricular zone between the *basal ganglia and the lateral cortex. Lateral nucleus (amygdala) – The most lateral nucleus in the *basolateral complex of the *amygdala. Cells from the *lateral migratory stream appear to enter the nucleus at the distinctive saw-toothed lateral edge. This nucleus is a major recipient of cortical input from the *temporal lobe, *occipital lobe, *insular gyrus, and *orbital gyrus. It also gets input from the *posterior complex of the thalamus. It projects to the *entorhinal cortex, *temporal cortex, *orbital cortex, *insular cortex, *nucleus accumbens, and *dorsomedial thalamic nucleus. Lateral preoptic area – An anterior continuation of the lateral hypothalamic area in the *preoptic area. Lateral reticular nucleus – A relatively discrete group of neurons in the caudal medulla, dorsolateral to the *inferior olive. The neurons of this precerebellar relay nucleus receive topographic exteroceptive and proprioceptive afferents from the *spinocephalic tract and project ipsilaterally to the *cerebellum via the *inferior cerebellar peduncle. Lateral septal nucleus – An indistinct gray mass in the lateral *septum that is closely associated with the *fornix, which provides input to these neurons. Lateral tuberal nucleus (hypothalamus) – Two or three distinct spherical masses near the inferior surface of the *lateral hypothalamic area. These neurons may play a role in thermoregulation and food intake. Lateral ventricles – Paired cavities of the ventricular system in the telencephalon. They are connected with the *third ventricle in the diencephalon by the *foramen of Monro.

375 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. Lateral ventricles (embryonic) – During embryonic development, the *neuroepithelium lining the hypertrophied lateral ventricles and the adjacent subventricular zone are the source of neurons and neuroglia in the telencephalon. In the mature brain the enduring shrunken regions of the lateral ventricles are lined by cells of the *ependyma. Lateral vestibular nucleus – Also called Deiter’s nucleus. A collection of large neurons lying dorsolaterally along the wall of the *fourth ventricle. It receives primary sensory input from the vestibular ganglion via cranial *nerve VIII and its large neurons are the source of the vestibulospinal tract. Smaller neurons send axons to vestibular areas of the cerebellum and to the *medial longitudinal fasciculus. Layer I (cerebral cortex) – The cell-sparse layer beneath the pia in all parts of the *cerebral cortex. This is the first cortical layer to develop and contains the earliest generated cortical neurons, the Cajal-Retzius cells. Lingula (cerebellum I-II) – The ventral lobule of the anterior lobe of the *cerebellar vermis with a tongue-like projection over the surface of the *superior cerebellar peduncle. This lobule does not extend to the hemispheres. Lingula (occipital lobe) – Tongue-shaped gyrus beneath the *cuneus, ventral to the *calcarine fissure. Locus coeruleus – Aggregate of large pigmented cells in the *pons. It is the major source of ascending and descending noradrenergic fibers that are widely distributed throughout the central nervous system.

M Mammillary body – Distinctive region in the posteroventral hypothalamus, composed of the medial and lateral mammillary nuclei. Its principal afferents are from the *septum and *subiculum that course in the *fornix; its efferents form the *mammillothalamic and *mammillotegmental tracts. Mammillotegmental tract – Descending fiber bundle containing *mammillary body efferents to the brain stem, including the *dorsal tegmental nucleus. Mammillothalamic tract – Ascending fiber bundle containing efferents of the *mammillary body that terminate in the thalamic *anterior complex. Massa intermedia (thalamus) – Interthalamic bridge across the *third ventricle that contains several midline structures,

including the *reuniens nucleus and the thalamic *periventricular complex. Medial accessory olive – A small nucleus in the *inferior olive complex that contains densely packed neurons along the lateral border of the medial lemniscus. It receives proprioceptive input from the spinal cord and its efferents reach the contralateral cerebellum (mainly the vermis) by way of the *inferior cerebellar peduncle. Medial forebrain bundle – A diffuse fiber tract that extends from the *olfactory tubercle, through the *lateral hypothalamic area, to the *substantia nigra in the midbrain *tegmentum. It is more conspicuous in the brains of lower animals than in the human brain. Medial geniculate body – Principal thalamic relay station in the auditory pathway to the *cerebral cortex. Its afferents originate in the *trapezoid body, the *superior olivary complex, the *lateral lemniscus nuclei, and the *inferior colliculus. Its efferents form the *auditory radiation that terminates in the *temporal lobe. The connections with the cerebral cortex are reciprocal. Medial lemniscus – Large fiber bundle conveying tactile and other somatosensory input to the thalamus. It originates in the *gracile and *cuneate nuclei in the *medulla, crosses to the opposite side (sensory decussation), ascends through the *pons and *midbrain, and terminates in the *ventral posterolateral and *ventral posteromedial nuclei of the thalamus. Medial lemniscus (decussation) – Also known as the sensory decussation, a medial area in the lower *medulla, above the *pyramids, where axons of the medial lemniscus cross to the opposite side. Medial longitudinal fasciculus – A dorsomedial tract in the *midbrain, *pons and *medulla that contains ascending and descending fibers coursing beneath the *oculomotor nuclear complex, *trochlear nucleus, *abducens nucleus, and *hypoglossal nucleus. It turns ventrally in the posterior medulla and extends into the ventral funiculus of the cervical spinal cord. Its ascending axons originate throughout the *vestibular nuclear complex. Its descending axons originate in the *medial vestibular nucleus and the *reticular formation. Medial nucleus (amygdala) – Part of the *corticomedial complex that contains more loosely packed small-to-medium sized cells than the adjacent *cortical nucleus. It gets input from

GLOSSARY

layer III of the *primary olfactory cortex, thalamic *periventricular complex, hypothalamic *ventromedial nucleus, and *lateral hypothalamic area. It projects to the *orbital cortex, thalamic *periventricular complex, and *ventromedial hypothalamic nucleus. Medial preoptic nucleus – A rounded mass of neurons in the *medial preoptic area that plays a role in sexual functions. Medial septal nucleus – An indistinct nucleus in the midline septum that is continuous with the vertical limb of the *diagonal band of Broca. Medial vestibular nucleus – Component of the *vestibular nuclear complex situated underneath the *fourth ventricle medial to the other vestibular nuclei. Its neurons receive primary sensory input from the vestibular ganglion via cranial *nerve VIII and project to the *fastigial nucleus, the *flocculus *nodulus, and *uvula. Medial vestibular axons also extend through cervical levels of the spinal cord in the *medial longitudinal fasciculus. Median preoptic nucleus – A small nucleus in the *preoptic area that forms a narrow cap around the *anterior commissure in the midline. Medulla – Region of the neuraxis surrounding the posterior *fourth ventricle, also known as the medulla oblongata, bounded by the *pons rostrally and the *spinal cord caudally. An extremely heterogeneous region containing sensory, somatic motor, and visceral motor nuclei as well as large ascending, descending, and decussating fiber tracts. Medullary neuroepithelium – Primary germinal matrix that lines the core and recesses of the posterior embryonic *fourth ventricle. Its several subdivisions are the source of neurons and glia of the different sensory, relay and motor nuclei of the medulla. During the third trimester, the medullary neuroepithelium has already been transformed into a glioepithelium/ependyma. See also Precerebellar neuroepithelium. Medullary layer (cerebellar cortex) – The deep white matter in the *cerebellar cortex. It contains ascending climbing and mossy fibers and descending Purkinje cell axons. Mesencephalic neuroepithelium – Primary germinal matrix that lines the embryonic *aqueduct. Its different subdivisions produce neurons and glia for the *superior colliculus, the *inferior colliculus, the *central gray, and the *tegmentum.

376

GLOSSARY


In the third trimester, this germinal matrix has already been transformed into a glioepithelium/ependyma. Mesencephalic nucleus (V) – Large neurons scattered along the lateral border of the *central gray of the midbrain and pons. They are primary sensory neurons that enter the brain from the periphery early in development relaying proprioceptive information from the muscles of mastication. They may function in the reflex control of bite strength.

The neocortex is considered to be a phylogenetically more recent laminated telencephalic structure than the “threelayered” *allocortex.

Meyer’s loop – Part of the visual radiation that curves into the temporal lobe on its way to the *occipital lobe.

Neocortical neuroepithelium – Extensive primary germinal matrix that lines the dorsal and lateral walls of the hypertrophied embryonic *lateral ventricles. The nuclei of the dividing cells shuttle to the lumen of the ventricle to undergo mitotic division there. It is the ultimate source of neurons and glia in the neocortex and some other structures, such as the *primary olfactory cortex and the *basolateral complex of the amygdala.

Midbrain – The most anterior part of the brainstem divided into the *tectum (“roof”) and the *tegmentum (“floor”).

Neocortical stratified transitional field – See Stratified transitional field (cortical).

Midbrain tectum – See Tectum.

Neocortical subventricular zone – A *secondary germinal matrix situated either above the *neocortical neuroepithelium or, after dissolution of the *neuroepithelium, adjacent to the *lateral ventricle *ependyma. It is derived from the primary cortical neuroepithelium but is distinguished from it in that the nuclei of its proliferating cells do not shuttle to the lumen of the ventricle during mitosis.

Midbrain tegmentum – See Tegmentum. Middle cerebellar peduncle – Massive tract of *pontocerebellar fibers that originate in the *pontine gray and enter the cerebellum posterolateral to the *inferior cerebellar peduncle. Molecular layer (cerebellar cortex) – Superficial layer that contains the dendrites of Purkinje cells, the parallel fibers (axons) of granule cells, the climbing fibers of the *inferior olive, and the small basket and stellate cells and their processes. Molecular layer (dentate gyrus) – Superficial fibrous layer of the hippocampal *dentate gyrus. It contains the dendrites of granule cells, some scattered neurons, and axon terminals from multiple sources. Motor nucleus, V – See Trigeminal, motor nucleus. Motor nucleus, VII See Facial, motor nucleus. Myelination gliosis – Sometimes called premyelination gliosis. Transient increase in the concentration of proliferating glia in fiber tracts before the onset of myelination. It is evident during late fetal development in the *cuneate fasciculus and deep parts of the *gracile fasciculus.

N Neocortex – The “six-layered” cortex of the cerebral hemispheres, also known as the isocortex. Its principal divisions are the *frontal lobe, the *paracentral lobule, the *parietal lobe, the *occipital lobe, the *temporal lobe, and the *insula.

Nerve III (oculomotor) – Cranial motor nerve originating in the *oculomotor nuclear complex. It innervates all the extraocular muscles – except the lateral rectus and superior oblique – and the skeletal muscles of the eyelid, the smooth sphincter muscles of the iris, and the ciliary muscles of the lens. Nerve IV (trochlear) – Cranial motor nerve composed of axons of the *trochlear nucleus that innervates the superior oblique muscle of the eye. This nerve is unique because it exits from the dorsal surface of the *midbrain behind the *inferior colliculus. Nerve V (trigeminal) – A mixed sensory and motor cranial nerve that has three peripheral branches, the ophthalmic, the maxillary, and the mandibular. All three branches contain peripheral sensory fibers from the trigeminal ganglion that terminate in the *trigeminal principal sensory nucleus, the *trigeminal spinal nucleus, and the substantia gelatinosa in upper cervical segments of the spinal cord. A bundle of fibers in the mandibular branch, originating in the *trigeminal motor nucleus, innervates the muscles of mastication. Nerve VI (abducens) – A motor cranial nerve that originates in the *abducens nucleus and emerges near the midline at the

caudal border of the *pons. The fibers innervate the lateral rectus muscle of the eye. Nerve VII (facial) – A mixed sensory and motor nerve, the facial nerve has three components. Primary sensory gustatory fibers from the geniculate ganglion enter the solitary tract and terminate in the *solitary nucleus. Somatic motor fibers from the *facial motor nucleus innervate the muscles of facial expression. Visceral motor (parasympathetic) fibers from preganglionic neurons in the dorsolateral pontine *reticular formation (the indistinct salivatory nucleus) target the pterygopalatine and submandibular ganglia. Nerve VIII (cochlear, vestibular) – A sensory cranial nerve that contains primary auditory afferents from the spiral ganglion in the cochlea and primary vestibular afferents from the vestibular (Scarpa’s) ganglion. The auditory afferents terminate in the dorsal and ventral *cochlear nuclei. The vestibular afferents terminate in the nuclei of the *vestibular nuclear complex and some reach the cerebellar *nodulus and *flocculus. Nerve IX (glossopharyngeal) – A mixed sensory and motor cranial nerve that exits the *medulla between the *inferior olive and the *inferior cerebellar peduncle. The sensory part of nerve IX relays gustatory input from the posterior third of the tongue and visceral sensory input from the tonsils, the Eustachian tube, and the carotid sinus via primary sensory neurons in the superior and inferior (nodose) ganglia. These fibers enter the solitary tract and terminate in the *solitary nucleus. The somatic motor part of nerve IX originates in the *nucleus ambiguus and innervates the pharyngeal and laryngeal muscles. The visceral motor fibers from parasympathetic preganglionic neurons in the salivatory nucleus terminate in the otic ganglion. Nerve X (vagus) – A mixed sensory and motor nerve, with some somatic and many visceral afferents and efferents (parasympathetic) that are widely distributed throughout the body, including the pharynx, larynx, trachea, esophagus, and all the thoracic and abdominal viscera. Vagal afferents terminate in the *solitary nucleus and other medullary sites. Most of its preganglionic motor neurons are located in the *dorsal motor nucleus (X). Nerve XI (accessory) – This nerve has a cranial and a spinal component. The cranial motor fibers innervate the intrinsic muscles of the larynx and the spinal motor fibers innervate the sternocleidomastoid and upper trapezius muscles. The spinal fibers originate in a column of motoneurons that

377 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. extends from the region of the *nucleus ambiguus to the 5th-6th segments of the cervical *spinal cord. Nerve XII (hypoglossal) – A somatic motor cranial nerve that originates in the *hypoglossal nucleus and leaves the *medulla between the *pyramids and the *inferior olive. The fibers innervate the intrinsic and extrinsic muscles of the tongue. Neuroepithelium – The primary source of the neurons and glia in the central nervous system. The neuroepithelial stem cells initially form the neural plate, which folds to form the neural groove. After closure of the neural tube caudally and of the cephalic vesicles rostrally, the *ventricles form and henceforth the nuclei of neuroepithelial stem cells shuttle to the ventricular lumen to undergo mitosis. The neuroepithelium is divisible into mosaic regions or patches that give rise to neurons and glia of distinct brain structures or cell types. The identified patches are listed seperately, e.g. *frontal neuroepithelium. The neuroepithelium is the source of several *secondary germinal matrices that also generate neurons. As neurogenesis ceases, the pluripotential neuroepithelium is transformed at many sites into a *glioepithelium, such as the *callosal glioepithelium or the *fornical glioepithelium, or into the *ependyma that lines the enduring ventricles. Nodulus (cerebellum X) – Cerebellar lobule coextensive with the *inferior lobe of the cerebellar vermis. It is separated from the *posterior lobe by the *posterolateral fissure. It is continuous, via the floccular peduncle, with the *flocculus in the hemisphere. The nodulus gets extensive primary vestibular input from the vestibular ganglion and secondary input from the *vestibular nuclear complex. Nucleus accumbens – Ganglionic component of the ventral telencephalon ventromedial to the *striatum. It is distinguished from the striatum by its cellular organization, neurochemical composition, and intimate connections with the *hypothalamus, *amygdala, and other parts of the limbic system. Nucleus ambiguus – Aggregate of somatic motor neurons that form a thin column in the ventrolateral medulla. Its axons innervate the muscles of the larynx and pharynx via *nerve IX. Nucleus of the lateral lemniscus (dorsal) – Interstitial neurons in the *lateral lemniscus ventral to the *inferior colliculus with input from the *cochlear nuclei and the *superior olivary complex. Its axons join the lateral lemniscus to terminate bilaterally in the *inferior colliculus and the *medial geniculate body.

Nucleus of the lateral lemniscus (ventral) – Interstitial neurons in the *lateral lemniscus lateral to the *superior olivary complex. Input and output are similar to the dorsal nucleus of the lateral lemniscus. Nucleus of the lateral olfactory tract (amygdala) – A small mass of densely-stained neurons located deep to the lateral *olfactory tract and superficial to the medial part of the cortical nucleus. These neurons are reciprocally connected to the *olfactory bulb. Nucleus of Roller – A large-celled nucleus ventral to the *hypoglossal nucleus. Sometimes classified as a component of the perihypoglossal nuclear complex.

O Occipital lobe – The most posterior region of the cerebral cortex, partially separated from the *parietal lobe by the *parietooccipital sulcus. It contains several visual areas with direct projections from the retina, by way of the *lateral geniculate body, or indirect projection by way of the *pulvinar. The distinctive primary visual projection area, the *striate cortex, lies along the wall of the *calcarine sulcus. Occipital neuroepithelium – Putative source of the neurons and glia of the occipital lobe. It is flanked in the fetal neocortex by the occipital subventricular zone and the distinctive *stratified transitional field before all its neurons settle in the visual cortex. Oculomotor nerve (III) – See Nerve III. Oculomotor nuclear complex – Situated at the base of the *central gray beneath the *aqueduct, the cell columns of this complex extend from the anterior pole of the *superior colliculus rostrally to the *trochlear nucleus caudally. Its somatic motor nuclei innervate the medial rectus, inferior rectus, superior rectus and inferior oblique muscles of the eye, and are associated with the fibers of the *medial longitudinal fasciculus. Most prominent of its autonomic (preganglionic) components is the dorsally located Edinger-Westphal nucleus. Olfactory bulb – Laminated brain structure where the first-order fibers of the olfactory nerve terminate and the second-order fibers of the lateral and medial *olfactory tracts originate. It is composed of three classes of neurons: large mitral cells, the intermediate tufted cells, and the small granule cells. The late-generated granule cells migrate to the olfactory bulb by way of the *rostral migratory stream.

GLOSSARY

Olfactory peduncle – A stalk that connects the olfactory bulb to the brain. It contains the *olfactory tract and the anterior olfactory nucleus. During the third trimester, the olfactory peduncle contains the *rostral migratory stream in its core. Olfactory tubercle – Paleocortical area in the ventral telencephalon deep to the *diagonal band of Broca (vertical limb) and superficial to the *nucleus accumbens/ventral *striatum. It contains many dense cellular aggregates, the *islands of Calleja. Input comes mainly from the lateral *olfactory tract. Olfactory tract – Large fiber bundle that originates in the *olfactory bulb and has two parts, the larger lateral olfactory stria and the smaller medial stria. The fibers of the lateral stria terminate in the *olfactory tubercle, the *primary olfactory cortex, and *corticomedial complex of the amygdala. Optic chiasm – Site of the partial decussation of fibers of the *optic nerve. Fibers from the nasal half of each retina cross here to the opposite side while those from temporal half proceed uncrossed to form the *optic tract. Optic nerve – The large second cranial nerve containing the axons of retinal ganglion cells. Beyond the *optic chiasm this nerve is called the *optic tract. Optic tract – Large bundle of crossed and uncrossed retinal afferents. In the human brain the majority of the fibers terminate in the *dorsal lateral geniculate nucleus; others proceed to the *superior colliculus, the *suprachiasmatic nucleus, and the *pretectum. Orbital gyrus – Ventromedial region of the *frontal lobe with afferents from the thalamic dorsomedial nucleus and efferents to the *preoptic area and the *hypothalamus. The region has been implicated in such visceromotor functions, as the regulation of blood pressure, respiratory rate, and gastric motility.

P Parabigeminal nucleus – This small nucleus, composed of a dorsal and ventral aggregate of cells in the lateral wall of the *midbrain tegmentum, receives second-order visual input from the *superior colliculus. It may be the homologue of the isthmo-optic nucleus of lower vertebrates. Parabrachial nucleus – Dorsolateral pontine structure with indistinct boundaries that surrounds the *superior cerebellar

378

GLOSSARY


peduncle. Its principal input comes from the *solitary nucleus and its efferents target the *ventral posteromedial nucleus of the thalamus, the *amygdala, and the *insular cortex. This nucleus has been implicated in gustatory and related visceral functions. Paracentral lobule, cortical – Inclusive term used for two neocortical convolutions surrounding the *central sulcus: the *precentral gyrus and the *postcentral gyrus. The term is used to distinguish these primary motor and sensory projection areas from the higher-order, integrative areas of the *frontal lobe anteriorly and the *parietal lobe posteriorly. Paracentral neuroepithelium – Putative source of the neurons and glia of the *paracentral lobule in the developing neocortex. It is flanked by the paracentral *subventricular zone and the paracentral *stratified transitional field before all the neurons settle in the cortical plate.

and vasopressin that reach the posterior pituitary gland by axoplasmic flow. The small neurons of the nucleus are the source of releasing hormones conveyed to the portal vessels of the median eminence. Paraventricular nucleus (thalamus) – Component of the *periventricular nuclear complex of the thalamus. Parietal lobe – Region of the neocortex bounded anteriorly by the *postcentral sulcus and posteriorly by the *parietooccipital sulcus. It subdivisions have been implicated in higher-level perceptual and cognitive functions, including language comprehension. Its major convolutions include the superior parietal lobule, the precuneus, the supramarginal gyrus, and the angular gyrus.

Paracentral nucleus, thalamic – Component of the *periventricular complex of the thalamus.

Parietal neuroepithelium – Putative source of the neurons and glia of the parietal lobe in the developing neocortex. It is flanked by the parietal *subventricular zone and the parietal *stratified transitional field before all the neurons settle in the cortical plate.

Parafascicular nucleus, thalamic – Component of the *periventricular complex of the thalamus.

Parieto-occipital sulcus – Fissure that partially separates the *parietal lobe and the *occipital lobe.

Paraflocculus (cerebellum HIX) – Also called the tonsil. Lobule of the cerebellar hemisphere that is connected to the *uvula in the vermis.

Parolfactory gyrus – Anteromedial gyrus in the frontal lobe, situated beneath the genu of the corpus callosum and in front of the *anterior commissure.

Parahippocampal gyrus – Transitional (allocortical-to-neocortical) area between *Ammon’s horn of the hippocampus and the isocortex of the *temporal lobe. Its subdivisions are the *subicular complex and the *entorhinal cortex.

Peristriate cortex – Area forming a belt around the *striate cortex and implicated in the higher-order processing of visual information.

Parahippocampal neuroepithelium – Putative source of the neurons and glia of the parahippocampal gyrus. It is flanked by the parahippocampal *subventricular zone and the parahippocampal *stratified transitional field before all its neurons settle in the cortical plate. Parasubiculum – *Allocortical component of the *parahippocampal gyrus between the *presubiculum and the *entorhinal cortex. Paratenial nucleus (thalamus) – Component of the *periventricular complex of the thalamus. Paraventricular nucleus (hypothalamus) – Prominent neuroendocrine structure abutting the third ventricle with a magnocellular and a parvocellular division. The large neurons of the paraventricular nucleus are the source of oxytocin

Periventricular complex (thalamus) – Collective term for several thalamic nuclei lining the third ventricle, including the *paracentral, *parafascicular, *paratenial, *paraventricular, and *reuniens nuclei. Its principal connections are with limbic system structures and the *striatum; connections with the *neocortex are sparse. Pineal gland – An endocrine gland connected by its stalk to the pineal recess of the dorsal *third ventricle. It secretes melatonin and other indoleamines. It is believed to receive indirect visual input from the retina. Piriform cortex – see Primary Olfactory Cortex. Pons – Region of the brain surrounding the anterior *fourth ventricle, situated between the *midbrain and the *medulla. It contains many ascending, descending and decussating fiber tracts, sensory and motor nuclei of the cranial nerves,

the *reticular formation, the *raphe nuclear complex, and the *pontine gray. Pontine gray – Large nucleus composed of a dense aggregate of small to medium-sized neurons in the ventral *pons. It contains the thick bundles of the longitudinally-oriented *corticofugal tract and the thinner bundles of the transverselyoriented *pontocerebellar fibers. Corticofugal axons that collateralize here are the principal afferents of the pontine gray neurons that are the source of the pontocerebellar fibers. Pontocerebellar fibers – Axons of pontine gray neurons that terminate in the *granular layer of the *cerebellar cortex. Pontocerebellar fibers (decussation) – Axons of pontine gray neurons that cross the midline and enter the contralateral *middle cerebellar peduncle. Postcentral gyrus – Convolution of the *cerebral cortex between the *central sulcus and the postcentral sulcus. It is the primary somatosensory projection area of the cortex and is classified as a component of the *paracentral lobule. Posterior commissure – Early developing decussating fiber tract in the dorsal *midbrain that interconnects several pretectal and tectal nuclei. Posterior complex (thalamus) – Division of the thalamus that includes the *lateral geniculate body, the *medial geniculate body, and the *pulvinar. The nuclei of the thalamic posterior complex – together with the *ventral complex – constitute the dedicated sensory relay system that supplies the neocortex with high-resolution and fast visual, auditory and somesthetic information. Posterior lobe (cerebellum IX) – The vermal lobe that is coextensive with the *uvula. It is separated from the *central lobe by the *secondary fissure and from the *inferior lobe by the *posterolateral fissure. Posterolateral fissure (cerebellum) – The vermal fissure that separates the *inferior lobe and the *posterior lobe. Precentral gyrus – Anterior convolution of the *paracentral lobule in the *cerebral cortex between the precentral sulcus and the *central sulcus. It constitutes the primary motor cortex with giant Betz pyramidal cells in layer V. Precerebellar neuroepithelium – Dorsal medullary germinal matrix whose cells migrate rostrally to the pons and caudally to the

379 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. ventral medulla to settle in the precerebellar nuclei, including the *pontine gray, the *reticular tegmental nucleus, the *inferior olive, the *lateral reticular nucleus, and the *external cuneate nucleus. This part of the germinal matrix is a *glioepithelium/ependyma during the third trimester. Preculminate fissure (cerebellum) – A fissure within the anterior lobe of the vermis that separates the *centralis from the *culmen. Premammillary area – Region with ill-defined boundaries anterior to the *mammillary body in the *hypothalamus. Preoptic area – Midline area surrounding the preoptic recess of the *third ventricle. It is contiguous anteriorly with the ventral telencephalon and blends posteriorly with the anterior *hypothalamus. It is implicated in the regulation of sexual behavior and reproductive functions. Prepositus nucleus – Situated in the dorsomedial *medulla, it extends from the anterior part of the *hypoglossal nucleus to the posterior part of the *abducens nucleus. Prepyramidal fissure (cerebellum) – Fissure in the vermal *central lobe that separates the *pyramis from the *tuber. Presubiculum – *Allocortical component of the *parahippocampal gyrus between the *subiculum and the *parasubiculum. Pretectum – Dorsal area between the posterior *thalamus and the *superior colliculus. Several of its nuclei are involved in visuomotor functions. Primary fissure (cerebellum) – Dorsal cerebellar fissure that extends from the vermis to the hemispheres. In the vermis, it separates the *anterior lobe from the *central lobe. In the hemispheres, it separates HI-HV of the anterior lobe from the *simplex lobule (HVI). Primary olfactory cortex – Paleocortical region, also called the piriform lobe or cortex, where fibers of the lateral olfactory tract terminate. It is situated rostral to the *entorhinal cortex of the *parahippocampal gyrus and includes the prepiriform area along the rhinal fissure and the periamygdaloid area. Primary visual cortex – See Striate cortex. Principal sensory nucleus (V) – See Trigeminal, principal sensory nucleus.

Pulvinar (thalamus) – Large nucleus of the thalamic *posterior complex. Its subdivisions send fibers to various regions of the *parietal lobe, *occipital lobe, *temporal lobe, and perhaps also to the frontal eye field. Purkinje cell layer (cerebellar cortex) – The monolayer of cell bodies of Purkinje cells sandwiched between the superficial *molecular layer and the deep *granular layer. During development, Purkinje cells are piled on top of one another but gradually form a monolayer as the surface area of the cerebellar cortex expands. Putamen – Lateral component of the *striatum. It lies between the *external capsule and the *globus pallidus. It is the major source of striatal efferents to the *thalamus, *subthalamic nucleus, *substantia nigra, and *tegmentum. Pyramid (corticospinal tract) – Paired triangular-shaped masses of fibers on the ventral surface of the lower medulla that contain the *lateral and *ventral corticospinal tracts. Pyramidal decussation – The region in the lower *medulla where the bulk of the fibers in the *pyramids cross the midline in a dorsolateral direction and descend in the spinal cord as the *lateral corticospinal tract. Pyramis (cerebellum VIII) – Triangular vermal lobule in the posterior *central lobe that is continuous with the paramedian and *biventral lobules of the cerebellar hemispheres. It is bounded anteriorly by the *prepyramidal fissure and is separated from the *posterior lobe by the *secondary fissure.

R Raphe migration – Streams of cells that originate in the dorsal *medullary neuroepithelium and are distributed in the midline ventrally during late-fetal development. They appear to contribute cells to the medullary *arcuate nucleus. Raphe nuclear complex – Several smaller and some larger cell aggregates that extend in and near the midline from the *midbrain rostrally to the *medulla caudally. The raphe cells are the principal source of serotonin-containing fibers distributed along the entire neuraxis from the forebrain to the *spinal cord. They are involved, as neuromodulators, in the regulation of sleep, wakefulness and emotional arousal. Red nucleus – Spherical mesencephalic nucleus with a small-celled (parvocellular) and a large-celled (magnocellular) division.

GLOSSARY

It is surrounded and traversed by fibers of the *superior cerebellar peduncle. Its afferents originate in the *cerebellar deep nuclei and the *cerebral cortex. Its descending efferents target various tegmental and medullary nuclei, and the *spinal cord (rubrospinal tract); its ascending fibers terminate in the *thalamus. The red nucleus is a component of the cerebellar feedback loop. Reticular belt (thalamus) – Distinctive component of the thalamus; it is coextensive with the thalamic *reticular nucleus. Reticular formation – A large collection of scattered neurons, enmeshed in a complex network of fibers, in the core of the *medulla, *pons, and *midbrain. The extensive axonal branches of neurons have have a modulatory influence on the entire central nervous system. Reticular tegmental nucleus (pons) – Situated dorsal to the *pontine gray, this precerebellar nucleus, also known as the nucleus reticularis tegmenti pontis, receives afferents from the *cerebellum and the *cerebral cortex. The principal target of its efferents is the cerebellum, where they terminate as mossy fibers. Reticular nucleus (thalamus) – A thin belt of cells and fibers between the wall of the *thalamus and the *internal capsule. Virtually all fibers that interconnect the thalamus and the cerebral cortex traverse, and probably form connections with, the thalamic reticular nucleus. Retrofacial nucleus – Small structure in the medulla caudal to the *facial motor nucleus and near the *nucleus ambiguus. Retrosplenial area (cingulate gyrus) – Region of the cingulate gyrus that wraps around the splenium of the *corpus callosum. Reuniens nucleus (thalamus) – Midline component of the *periventricular complex of the thalamus, situated in the *massa intermedia. Rostral migratory stream – A large stream of mitotic and postmitotic cells in the forebrain extending from the rostral *lateral ventricle to the *olfactory bulb. It is a source of neurons – such as the late-generated granule cells of the olfactory bulb – and neuroglia, and persists after the *neuroepithelium has receded or disappeared at most brain sites.

380

GLOSSARY


S

Spinal nucleus (V) – See Trigeminal, spinal nucleus.

Secondary fissure (cerebellum) – Fissure in the midline vermis that separates the *posterior lobe from the *central lobe.

Spinal tract (V) – See Trigeminal, spinal tract.

Secondary germinal matrix – Layer or field of proliferative precursors of neurons and glia outside the primary *neuroepithelium. These cells are progeny of the stem cells of the primary neuroepithelium that persist for varying periods after the neuroepithelium has disappeared. Examples of secondary germinal matrices are the *external germinal layer of the cerebellum, the *subventricular zone of the neocortex, the *subgranular zone of the dentate gyrus, the *rostral migratory stream, and the *striatal subventricular zone. Typically, the secondary germinal matrices are the source of late-generated small interneurons, or microneurons. Septum – Midline telencephalic structure beneath the anterior *corpus callosum that is better developed in lower mammals than in man. It contains *medial and *lateral nuclei. Its principal connections are with the *hippocampus and the *hypothalamus by way of the *fornix. The septum is a focal component of the limbic system. Sexually dimorphic nucleus – A small, dense cluster of neurons closely associated with the *medial preoptic nucleus in the *preoptic area. Simplex lobule (cerebellum HVI) –Lobule in the cerebellar hemisphere that is continuous with the vermal *declive. It is delineated anteriorly by the *primary fissure and posteriorly by *crus I of the ansiform lobule. Solitary tract and nucleus – This tract contains primary sensory fibers that reach the *medulla by way of cranial *nerves VII, IX, and X, conveying gustatory (VII and IX) and visceral sensory information (IX and X) to the solitary nucleus. The *dorsal sensory nucleus of X and the *commissural nucleus of X are part of this nuclear complex. Spinal cord – Caudal tubular component of the central nervous system that surrounds the *central canal. Its continuous core of gray matter (the dorsal horn, intermediate gray and ventral horn) and surrounding white matter (the dorsal, *lateral and ventral funiculi) are divided into 31 segments by the discontinuous entry of dorsal root afferents and exit of ventral root efferents that form the mixed spinal nerves. The cervical enlargement and the lumbar enlargement of the spinal cord supply the nerves of the forelimbs and hind limbs, respectively.

Spinocephalic tract – Large ascending fiber tract in the *lateral funiculus of the spinal cord whose fibers or collaterals are widely distributed throughout the *medulla, *pons, *midbrain, *thalamus, and the limbic forebrain. The spinocephalic tract, which includes the spinoreticular, spinomesencephalic and spinothalamic tracts, conveys nociceptive and other affective stimuli to the brain. It is distinguished from the phylogenetically more recent ascending *cuneate and *gracile funiculi that convey primarily cognitive somesthetic information to the neocortex. Spinocerebellar tracts – Several ascending pathways, including the dorsal and ventral spinocerebellar tracts in the *lateral funiculus that convey proprioceptive information from muscles and joints to the *cerebellum. Stratified transitional field – Transient intermediate field in the fetal *cerebral cortex between the *neuroepithelium (or *subventricular zone) and the *cortical plate. It is a crisply laminated site with alternating fiber-rich and cellrich layers that vary in their configuration in different lobes of the cerebral cortex; e.g., frontal stratified transitional field; occipital stratified transitional field. The different fibrous layers are continuous with the incoming thalamocortical afferents, the outgoing corticofugal efferents, and the decussating fibers of the *corpus callosum. The cellular layers are composed of sojourning and migrating neurons all of which eventually settle in the *cortical plate. Stria medullaris (thalamus) – Mediodorsal fiber bundle in the diencephalon coursing in an anteroposterior direction and terminating in the *habenular nuclei. Striatal neuroepithelium – Primary germinal source of neurons of the *caudate nucleus, *putamen, and *globus pallidus. It has a large anterolateral and anteromedial division, also known as the lateral and medial eminences, and a small posterior division that generates the neurons of the tail of the caudate nucleus. Striatal subventricular zone – A large *secondary germinal matrix flanking the striatal neuroepithelium that generates the bulk of the neurons of *caudate nucleus, *putamen and *globus pallidus. Striate cortex – Principal projection area of the *visual radiation, situated along the *calcarine sulcus. This distinctive thin

cortex is rich in small granule cells and contains a white band (of Gennari) within layer IV. Stria terminalis – Arched fiber bundle that originates in the corticomedial and basolateral *amygdala, courses along the medial surface of the *caudate nucleus, and terminates in the *bed nucleus of the stria terminalis, the anterior *hypothalamus, and the *preoptic area. Striatum – Term used for two components of the *basal ganglia: the *caudate nucleus and the *putamen. Strionuclear glioepithelium – Putative source of the glia of the stria terminalis, stria medullaris and possibly other nearby fiber tracts. Strionuclear neuroepithelium – Putative germinal source of the neurons and glia of the *bed nucleus of the stria terminalis. It is situated beneath the *striatal neuroepithelium in a notch of the *lateral ventricle near the *foramen of Monro. Throughout the third trimester, this germinal site is most likely the source of glia, and is labeled as the *strionuclear glioepithelium. Subcommissural organ – A highly vascularized circumventricular neuroendocrine organ located beneath the *posterior commissure in the roof of the posterior *third ventricle and anterior *aqueduct. It is devoid of neurons and may disappear from the human brain after birth. Subfornical organ – A highly vascularized circumventricular neuroendocrine organ situated between the two columns of the fornix at the confluence of the *third ventricle and the *foramen of Monro. Among its afferents are fibers from the *preoptic area and the anterior *hypothalamus. Its efferents target the hypothalamic *paraventricular nucleus and the *supraoptic nucleus. Subgranular zone (hippocampus) – A long-persisting secondary germinal matrix beneath the *granular layer of the dentate gyrus. It is a division of the *hippocampal neuroepithelium and is the source of late-generated dentate granule cells. Subicular complex – Collective term for the *parasubiculum, the *presubiculum and the *subiculum of the *parahippocampal gyrus. Subiculum – *Allocortical component of the *hippocampus, between CA1 and the *presubiculum.

381 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. Subpial granular layer – Transient cellular layer between *layer I and the pia in some regions of the developing *cerebral cortex. It may be a source of cortical glia. Substantia innominata – Extensive telencephalic area with indistinct boundaries beneath the *globus pallidus. A prominent component of the substantia innominata is the *basal nucleus of Meynert. Substantia nigra – Pigmented *midbrain tegmental structure abutting the base of the *internal capsule and the *cerebral peduncle. It has two components, the dopaminergic pars compacta, and the GABAergic pars reticulata. The substantia nigra receives afferents from the *striatum, *globus pallidus, the *bed nucleus of stria terminalis, the *central nucleus of the *amygdala, the *subthalamic nucleus, and the *raphe nuclear complex. Its dopaminergic efferents target the *striatum and some brainstem nuclei. Degeneration of the dopaminergic neurons of the substantia nigra have been implicated in Parkinson’s disease. Subthalamic nucleus – Biconvex diencephalic structure situated above the substantia nigra between the *zona incerta and the base of the *internal capsule. It has extensive reciprocal connections with the *globus pallidus, hence it is considered a component of the *basal ganglia circuitry. Subthalamic lesions produce persistent choroid movements (hemiballism) in the arms, legs and face. Subventricular zone – Secondary germinal matrix, derived from the primary *neuroepithelium. The subventricular zone flanks the neuroepithelium during early development and flanks the ependyma when the neuroepithelium dissolves. The proliferative cells of the subventricular zone, unlike those of the neuroepithelium, do not shuttle to the lumen of the ventricle during mitosis. Two large subventricular zones are located in the *cerebral cortex and the *striatum. Superior cerebellar peduncle – A large fiber tract of the *pons, also known as the brachium conjunctivum, that originates mainly in the *dentate nucleus and *interpositus nucleus. As the axons leave the cerebellum, they hug the dorsolateral wall of the pontine *fourth ventricle. As they approach the midbrain, they dip downward and cross the midline (decussation) posterior to the *red nucleus. Many of its axons terminate in the red nucleus, others continue rostrally and terminate in the *ventral anterior nucleus of the thalamus.

Superior colliculus – Anterior component of the *tectum, known in lower vertebrates as the optic lobe. A laminated structure, the superior colliculus is a direct target of optic nerve fibers. Its principal efferent outflow, by way of the tectobulbar and *tectospinal tracts, is to the medulla and spinal cord. Superior medullary velum – Thin membrane that covers the roof of the anterior fourth ventricle near the posterior border of the *tectum. The root fibers of cranial *nerve IV decussate here and exit the brain. Superior olivary complex – A group of neurons in the ventrolateral posterior *pons that receive auditory input from the dorsal and ventral *cochlear nuclei. Some of its axons cross the midline in the *trapezoid body. Ipsi- and contralateral fibers of the complex join the *lateral lemniscus and terminate in the *inferior colliculus and in the *medial geniculate body. Superior vestibular nucleus – This nucleus lies dorsal and anterior to the *lateral vestibular nucleus. It receives input from the vestibular ganglion, and projects to the *cerebellum, mainly the *nodulus, the *flocculus, and the *uvula. Suprachiasmatic nucleus (hypothalamus) – Small, paired midline structure above the *optic chiasm. It is implicated in the photic entrainment of the circadian rhythm. Suprageniculate nucleus (thalamus) – Wedge-shaped structure between the *pulvinar and the *pretectum, and dorsal to the *medial geniculate body. Supramammillary area (hypothalamus) – Hypothalamic region that caps the *mammillary body. Experimental studies in animals indicate that its cells project to the *dentate gyrus of the hippocampus. Supraoptic nucleus (hypothalamus) – Located above the optic tract lateral to the optic chiasm. The large secretory neurons of this nucleus produce arginine vasopressin and oxytocin that are conveyed by axoplasmic flow to the posterior lobe of the pituitary gland.

T Tectospinal tract – Efferent fiber tract that originates in the deep layers of the *superior colliculus, courses in the ventral funiculus of the spinal cord and terminates in the ventral horn of the *spinal cord. The tract may trigger involuntary

GLOSSARY

head rotation and body turning in response to visual stimulation. Tectum – Inclusive term for the dorsal hillocks that cap the *central gray of the midbrain and is the target of visual, auditory and somatosensory afferents. Its two discrete components are the *superior colliculus and the *inferior colliculus. Tegmentum – Ventral and ventrolateral region of the *midbrain and *pons with indistinct boundaries. It contains the *reticular formation, some discrete nuclei, and ascending, decussating, and descending fiber tracts. Some tegmental nuclei have been implicated in somatomotor and visceromotor functions. Temporal lobe – Lateral portion of the cerebral hemispheres. It is separated by the *lateral fissure from the *frontal lobe anteriorly and the *paracentral lobule dorsally, but is continuous with the parietal lobe dorsally and the *occipital lobe posteriorly. Two horizontal fissures, the superior and middle temporal sulci, divide the temporal lobe into three convolutions, the superior, middle and inferior gyri. The primary auditory area lies buried in the floor of the lateral fissure in the anterior transverse gyrus (Heschl’s gyrus). Temporal neuroepithelium – Putative source of neurons and glia in the temporal lobe neocortex. It is flanked during fetal development by the temporal *subventricular zone and the temporal *stratified transitional field before all the neurons settle in the *cortical plate. Tenia tecta – Components of the *cerebral cortex that extend into the dorsomedial *septum (dorsal tenia tecta) and medial *olfactory peduncle (ventral tenia tecta). Thalamocortical radiations – Collective term for the large afferent tracts that proceed from the thalamic *posterior complex and *ventral complex, by way of the internal capsule, to the somatosensory and motor projection areas of the *paracentral lobule, the auditory projection area of the *temporal lobe, and the *visual projection area of the occipital lobe. Thalamus – Massive dorsal diencephalic structure with several distinct and some indistinct nuclei. As a convenience, the thalamus is divided into the following nuclear regions: the *anterior complex, the *central complex, the *dorsal complex, the *periventricular complex, the *posterior complex, the *ventral complex, and the *reticular belt.

382

GLOSSARY


Third ventricle – Midline diencephalic component of the ventricular system. It is linked rostrally by the *foramen of Monro with the paired *lateral ventricles of the telencephalon, and caudally with the *aqueduct of the *midbrain. The dorsal region of the third ventricle is surrounded by the *thalamus, its ventral region and recesses by the *preoptic area and the *hypothalamus. During development, the neuroepithelium lining the third ventricle is the source of the neurons and glia of the diverse components the diencephalon. Trapezoid body – A fiber tract extending from the ventral *cochlear nucleus to the contralateral *superior olivary complex. It contains second- and higher-order auditory fibers. Transpontine corticofugal tract – Fibers of the corticofugal tract that traverse the *pontine gray nucleus. Collaterals of this tract synapse with neurons of the pontine gray that give rise to the *pontocerebellar fibers of the *middle cerebellar peduncle. Trigeminal, motor nucleus – Aggregate of trigeminal somatic motor neurons situated medial to the *trigeminal principal sensory nucleus. It receives input from the *mesencephalic nucleus (V) and from motor areas of the *cerebral cortex via relays in the pontine *reticular formation. Its axons leave the brain in cranial *nerve V and join its mandibular branch that innervates the muscles of mastication. Trigeminal, principal sensory nucleus – The second-order sensory neurons in the trigeminal system located dorsal and lateral to the incoming sensory root of cranial *nerve V. It receives topographic somatosensory input from the face and mouth, and its efferents cross the midline in the pons and proceed to the thalamic *ventral complex in close association with the *medial lemniscus. Trigeminal, spinal nucleus – A continuation of the *trigeminal principal sensory nucleus that extends caudally through the *medulla to the second cervical level of the *spinal cord. It receives topographic input from the face via somatosensory neurons in the trigeminal ganglion. The axons of the trigeminal spinal nucleus cross the midline, join the *medial lemniscus and proceed to the *ventral complex of the thalamus. Trigeminal, spinal tract – Primary sensory fibers of the trigeminal ganglion that convey touch and pressure information from the face. The axons enter the brain in the pons and proceed caudally, forming a lateral cap around the *trigemi-

nal spinal nucleus where they terminate in a topographic order.

(cerebellar and striatal) somatosensory and proprioceptive input to the sensory and motor areas of the *neocortex.

Trochlear nucleus – Aggregate of somatic motor neurons located posterior to the *oculomotor nuclear complex that innervate the superior oblique muscle of the eye by way of cranial *nerve IV.

Ventral corticospinal tract – A small complement of ipsilateral corticospinal fibers that do not cross in the *pyramidal decussation and descend in the ventral funiculus of the *spinal cord.

Tuber (cerebellum VIIb) – The vermal lobule posterior to the *folium. The tuber is continuous with *crus II of the ansiform lobule (HVIIA) and the paramedian lobule (HVIIB) in the hemispheres. Together with the folium, the tuber is a late-maturing region of *cerebellar cortex.

Ventral lateral nucleus (thalamus) – Situated caudal to the *ventral anterior nucleus, this component of the thalamic *ventral complex is the target of input from the *superior cerebellar peduncle and the *red nucleus. Its somatotopically organized efferents terminate in the motor cortex and adjacent areas. The ventral lateral nucleus may be the principal relay from the *cerebellum to the *neocortex.

U Uncinate fasciculus – A fiber tract in the temporal lobe that proceeds from the *uncus to the anterolateral *temporal lobe. It is infiltrated by cells in the *lateral migratory stream. Uncus – The rostral cap of the *parahippocampal gyrus. Uvula (cerebellum IX) – A large lobule in the *cerebellar vermis that is coextensive with the *posterior lobe, and is continuous with the *paraflocculus in the hemispheres. It is bounded anteriorly by the *secondary fissure, and posteriorly by the *posterolateral fissure. The uvula is part of the “vestibulo-cerebellum,” receiving massive input from the vestibular nuclear complex as well as primary sensory input from the vestibular ganglion.

V Ventral anterior nucleus (thalamus) – The ventral anterior nucleus, to be distinguished from the *anteroventral nucleus (which is a component of the *anterior complex of the thalamus) is the most rostral component of the thalamic *ventral complex. Its afferents come mostly from the *globus pallidus and the *substantia nigra, and its efferents terminate in the *paracentral lobule of the neocortex. The ventral anterior nucleus may be the principal relay from the *basal ganglia to the *neocortex. Ventral complex (thalamus) – A group of structurally and functionally related ventrolateral and ventral nuclei of the thalamus, including the *ventral anterior, *ventral lateral, *ventral posterolateral, and *ventral posteromedial nuclei. The ventral thalamic complex is the principal topographically organized relay system of direct (lemniscal) and indirect

Ventral posterolateral nucleus (thalamus) – Situated caudal to the *ventral lateral nucleus, this region of the thalamic *ventral complex is the target of fibers of the *medial lemniscus that originate in the *cuneate nucleus and the *gracile nucleus and convey somatosensory information from the trunk and the extremities. Its efferents form the somesthetic radiation that terminates in a precise topographic order in the medial part of the *postcentral gyrus. The ventral posterolateral nucleus is the principal thalamic relay of somesthetic input from the trunk and limbs to the *neocortex. Ventral posteromedial nucleus (thalamus) – Situated between the *ventral posterolateral nucleus and the *centromedian nucleus, this nucleus receives afferents from the *trigeminal sensory nuclei and the *parabrachial nucleus that convey sensory information from the face, the tongue, the oral cavity, and the neck. The efferents of this nucleus terminate in a precise topographic order in the lateral part of the *postcentral gyrus. The ventral posteromedial nucleus is the principal thalamic relay of somatosensory and gustatory input from the neck, head, and mouth to the *neocortex. Ventral tegmental area – Medial area flanking the *substantia nigra and containing a high concentration of dopaminergic neurons, much like the substantia nigra, pars compacta. It is generally considered as a component of the substantia nigra complex. Ventricles – The cerebrospinal fluid-filled system in the core of the brain that is divided into the paired *lateral ventricles in the telencephalon, the single *third ventricle in the diencephalon, the *aqueduct in the mesencephalon, and the *fourth ventricle in the pons and medulla. The fourth ventricle is

383 An asterisk in front of a term indicates that it has a separate entry in the Glossary with additional information. Terms referring to transient developmental structures are underlined. continuous caudally with the *central canal of the spinal cord. The lateral, third and fourth ventricles have a prominent *choroid plexus. Ventricles, embryonic –The ventricular system is proportionally larger during embryonic and fetal development than in the mature central nervous system. Initially it is lined throughout by the stem cells of the *neuroepithelium. As neurogenesis declines, the ventricles shrink considerably, and altogether disappear in many locations. At some sites, the proliferative *subventricular zone replaces the neuroepithelium, while at others the enduring ventricles are lined by the specialized cells of the *ependyma. Ventromedial nucleus (hypothalamus) – Large spherical nucleus that flanks the third ventricle and is surrounded by a fibrous shell. It has reciprocal connections with the *amygdala,

the *bed nucleus of the stria terminalis, the *septum, and the *subiculum. It has been implicated in motivational functions related to feeding and sexual behavior. Vermis – See Cerebellum (vermis). Vestibular nuclear complex – A large area in the dorsal medulla, composed of the *medial, the *lateral, the *superior, and the *inferior vestibular nuclei. These nuclei get primary sensory input from the vestibular ganglion; their efferents join the *medial longitudinal fasciculus and form the vestibulospinal tract. Visual radiation – Thalamocortical fibers beneath the cerebral *white matter that originate in the *lateral geniculate body and terminate in the *striate cortex of the occipital lobe.

GLOSSARY

W White matter – General term for extensive regions in the brain and spinal cord composed of myelinated fiber tracts but few or no neuronal cell bodies. In histological preparations with myelin stains, the white matter appears black. In laminated brain regions, as in the *cerebral cortex and the *cerebellar cortex, the white matter is called the medullary layer.

Z Zona incerta – Sheet of *gray matter at the base of the *thalamus. It is generally considered to be a rostral extension of the *tegmentum. *Forel’s fields are contiguous with the zona incerta.

The Human Brain During the Third Trimester

The Human Brain During the Early First Trimester (Atlas of Human Central Nervous System Development)

Atlas of the Human Brain, Third Edition

The Human Brain During the Late First Trimester (Atlas of Human Central Nervous System Development, Volume 4)

The Human Brain

The Human Brain

The Human Brain

Educating the Human Brain

The Human Brain

The Human Brain Book

Asimov, Isaac - The Human Brain

Asimov, Isaac - The Human Brain

Human Brain Proteome

The Human Brain: Prenatal Development and Structure

Atlas of the Human Brain, 3rd Edition

The Human Brain. A Guided Tour

Making Connections: Teaching and the Human Brain

Human Osteology, Third Edition

Human Parasitology, Third Edition

Brain Disorders Sourcebook, Third Edition

Memoranda During The War

The Runaway Brain: The Evolution of Human Uniqueness

Human Brain Function, Second Edition

The Tell-Tale Brain: Unlocking the Mystery of Human Nature

The Hot Brain: Survival, Temperature, and the Human Body

Survival of the Fattest: The Key to Human Brain Evolution

Philosophy of the Brain: The Brain Problem

Human Reproductive Biology, Third Edition

The Most Human Human

The Most Human Human

Self-Regulation: Brain, Cognition, and Development (Human Brain Development Series)

The Human Brain During the Third Trimester

The Human Brain During the Early First Trimester (Atlas of Human Central Nervous System Development)

Atlas of the Human Brain, Third Edition

The Human Brain During the Late First Trimester (Atlas of Human Central Nervous System Development, Volume 4)

The Human Brain

The Human Brain

The Human Brain

Educating the Human Brain

The Human Brain

The Human Brain Book

Asimov, Isaac - The Human Brain

Asimov, Isaac - The Human Brain

Human Brain Proteome

The Human Brain: Prenatal Development and Structure

Atlas of the Human Brain, 3rd Edition

The Human Brain. A Guided Tour

Making Connections: Teaching and the Human Brain

Human Osteology, Third Edition

Human Parasitology, Third Edition

Brain Disorders Sourcebook, Third Edition

Memoranda During The War

The Runaway Brain: The Evolution of Human Uniqueness

Human Brain Function, Second Edition

The Tell-Tale Brain: Unlocking the Mystery of Human Nature

The Hot Brain: Survival, Temperature, and the Human Body

Survival of the Fattest: The Key to Human Brain Evolution

Philosophy of the Brain: The Brain Problem

Human Reproductive Biology, Third Edition

The Most Human Human

The Most Human Human

Self-Regulation: Brain, Cognition, and Development (Human Brain Development Series)

Recommend Documents