Neuroanatomy This page intentionally left blank Second Edition Neuroanatomy Draw It to Know It Adam Fisch, MD JWM Neurology and Adjunct Professor of Neurology Indiana University School of Medicine Indianapolis, IN 1 1 Oxford University Press, Inc., publishes works that further Oxford University’s objective of excellence in research, scholarship, and education. Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi New Delhi Shanghai Taipei Toronto With offi ces in Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore South Korea Switzerland Th ailand Turkey Ukraine Vietnam Copyright © 2012 by Adam Fisch Published by Oxford University Press, Inc. 198 Madison Avenue, New York, New York 10016 www.oup.com Oxford is a registered trademark of Oxford University Press All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of Oxford University Press. _________________________________________________________________ Library of Congress Cataloging-in-Publication Data Fisch, Adam. Neuroanatomy : draw it to know it/Adam Fisch.—2nd ed. p.; cm. Includes bibliographical references and index. ISBN 978-0-19-984571-2 (pbk.) I. Title. [DNLM: 1. Nervous System—anatomy & histology. 2. Anatomy, Artistic—methods. 3. Medical Illustration. WL 101] 611.’8—dc23 2011037944 _________________________________________________________________ Th is material is not intended to be, and should not be considered, a substitute for medical or other professional advice. Treatment for the conditions described in this material is highly dependent on the individual circumstances. And, while this material is designed to off er accurate information with respect to the subject matter covered and to be current as of the time it was written, research and knowledge about medical and health issues is constantly evolving and dose schedules for medications are being revised continually, with new side eff ects recognized and accounted for regularly. Readers must therefore always check the product information and clinical procedures with the most up-to-date published product information and data sheets provided by the manufacturers and the most recent codes of conduct and safety regulation. Th e publisher and the authors make no representations or warranties to readers, express or implied, as to the accuracy or completeness of this material. Without limiting the foregoing, the publisher and the authors make no representations or warranties as to the accuracy or effi cacy of the drug dosages mentioned in the material. Th e authors and the publisher do not accept, and expressly disclaim, any responsibility for any liability, loss or risk that may be claimed or incurred as a consequence of the use and/or application of any of the contents of this material. 9 8 7 6 5 4 3 2 1 Printed in the United States of America on acid-free paper Th e fi rst edition of this book was dedicated to the memory of my younger brother, David. Th is edition is dedicated to my children, Ava and Ezra, who were born during the rewrite of this book and who renew my faith that good things still happen. This page intentionally left blank Foreword from the First Edition Neuroanatomy is a nightmare for most medical students. Th e complex array of nuclei, ganglia, tracts, lobes, Brodmann areas and cortical layers seem to the uninitiated as the height of useless trivia. My own memory of my neuroanatomy class in medical school is vivid. Our professor ordered each member of the class to buy a set of colored pencils—the kind you had in third grade. Each color was coded for particular structures (red for the caudate, green for the putamen, yellow for the claustrum and burnt sienna for the globus pallidus). At our senior play, which poked fun at our professors, a beleaguered medical student was asked to name the components of the basal ganglia. Without knowing what the structures even were or did, he responded “red, green, yellow, and burnt sienna.” Almost forty years later, this remains a class joke. Except for the handful of us who went into neurology, neurosurgery, and psychiatry, the basal ganglia to the rest of my class is just a fading joke from the distant past. And yet, no one can practice even rudimentary neurology without some basic under- standing of the neuroanatomy. Non-neurologists in particular, many of whom see large numbers of patients with neurological complaints, have no hope of sorting out common problems such as headache, dizziness, tiredness, fatigue, sleep disorders, numbness and tingling, and pain, without a reasonable grasp of how the nervous system is organized. Despite all of the marvelous advances in neuroscience, genetics, and neuroimaging, the actual practice of neurology, whether it is done by a neurologist or a non-neurologist, involves localizing the problem. Th e nervous system is just too complicated to skip this step. Without an organized approach based on a reasonable understanding of functional neuroanatomy, clinical neurology becomes incomprehensible. In his wonderful book, Neuroanatomy: Draw It to Know It , neurologist Adam Fisch applies my old neuroanatomy professor’s colored pencil idea in a manner that actually works, and it’s fun! Over the course of 39 chapters, most of the clinically important neu- roanatomically important subjects are covered, ranging through the overall organization of the nervous system, the coverings of the brain, the peripheral nervous system, the spinal cord, the brainstem, the cerebellum, and the cerebral cortex. It is clear that the book was written by an experienced neurologist, as the topics are organized in a fashion that illumi- nates the principle of anatomical pathophysiological correlation, which is the tool with which neurologists approach clinical problems. Th is book should be of great interest to all neurologists, neurosurgeons, neurology residents, and students of neurology. Others who see patients with neurological com- plaints, such as internists, emergency physicians and obstetrician-gynecologists should also review their neuroanatomy if they wish to provide excellent care to their patients. viii Foreword As any experienced teacher knows, one only really knows a subject when one can teach it oneself. By drawing the anatomy, the reader of this book literally teaches the subject to himself. By making it clinically relevant, the information learned in this manner is likely to stick. Adam Fisch has done us all a great service by rekindling the enjoyment in learning the relevant, elegant anatomy of the nervous system. Martin A. Samuels, MD, DSc(hon), FAAN, MACP Chairman, Department of Neurology Brigham and Women’s Hospital Professor of Neurology Harvard Medical School Boston, MA Preface Neuroanatomy is at once the most fascinating and most diffi cult subject in the fi eld of anatomy. When we master it, we can resolve the most perplexing diagnostic riddles in medicine, and yet we struggle with the numerous neuroanatomical structures and path- ways, the intertextual inconsistencies in nomenclature and opinion, and the complex spa- tial relationships. So here, we bring the diff erences in nomenclature and opinion to the forefront to mitigate them and we present the material in an active, kinesthetic way. In this book, we approach each neuroanatomical lesson by beginning fresh with a blank page, and from there we build our diagram in an instructive, rather than a didactic format. With each lesson, we create a schema that provides a unique place for each neuro- anatomical item. Th is, then, allows us to rehearse the schema and in the process memorize the fundamental neuroanatomical items. And because we are all students of anatomy— and not art—our purpose with each lesson is to learn a schematic that we can reproduce in the classroom, the laboratory, or at the bedside in a way that is especially designed for the “left -brained” among us. Some of us possess pigeon-like navigational skills, whereas others of us fi nd ourselves getting lost in our own houses. Th e ease with which we learn anatomy is inherently related to the strength of our spatial cognition, which makes it harder for those of us who struggle with complex spatial relationships to master the subject matter1 . When it comes to the task of deciphering a complicated illustration, specifi cally in studying the details of an illustration, it has been shown that we rely heavily on the right frontoparietal network2 – 4 . In Neuroanatomy: Draw It to Know It , we shift the process of learning neuroanatomy away from the classic model of spatial de-encoding, away from the right frontoparietal network, to the formulation of memorizable scripts or schemas, which task the prefrontal cortices more intensively, instead 5 , 6 . In so doing, we provide the less spatially-inclined with a diff erent entry zone into the world of neuroanatomy. Th is book reconciles the most burdensome impasses to our learning: we highlight inconsistencies, remove spatial complexities, and create an active, instructive text that adheres to the principle—when we can draw a pathway step by step, we know it. x Preface References 1 . Garg, A. X., Norman, G. & Sperotable, L. How medical students learn spatial anatomy. Lancet 357 , 363–364 (2001). 2 . Walter, E. & Dassonville, P. Activation in a frontoparietal cortical network underlies individual diff erences in the performance of an embedded fi gures task. PLoS One 6 (2011). 3 . Walter, E. & Dassonville, P. Visuospatial contextual processing in the parietal cortex: an fMRI investigation of the induced Roelofs eff ect. Neuroimage 42 , 1686–1697 (2008). 4 . Aradillas, E., Libon, D. J. & Schwartzman, R. J. Acute loss of spatial navigational skills in a case of a right posterior hippocampus stroke. J Neurol Sci 308 (2011). 5 . Knutson, K. M., Wood, J.