F O U R T H E D I T I O N Neuroscience for the Study of Communicative Disorders Subhash C. Bhatnagar, PhD, CCC-SLP Neurolinguistics Laboratory Speech Pathology and Audiology Department Marquette University BBhhaattnnaaggaarr__FFMM..iinndddd ii 1122//11//22001111 66::0011::4499 PPMM Senior Publisher: Julie Stegman Product Manager: John Larkin Marketing Director: Steven Rutberg Designer: Joan Wendt Compositor: SPi Global Fourth Edition Copyright © 2013, 2008, 2002, 1998 Lippincott Williams & Wilkins, a Wolters Kluwer business 351 West Camden Street Two Commerce Square Baltimore, MD 21201 2001 Market Street Philadelphia, PA 19103 Printed in China All rights reserved. This book is protected by copyright. No part of this book may be reproduced or transmitted in any form or by any means, including as photocopies or scanned-in or other electronic copies, or utilized by any information storage and retrieval system without written permission from the copyright owner, except for brief quotations embodied in critical articles and reviews. Materials appear- ing in this book prepared by individuals as part of their official duties as U.S. government employees are not covered by the above-mentioned copyright. To request permission, please contact Lippincott Williams & Wilkins at Two Commerce Square, 2001 Market Street, Philadelphia, PA 19103, via email at [email protected], or via website at lww.com (products and services). Library of Congress Cataloging-in-Publication Data Bhatnagar, Subhash Chandra. Neuroscience for the study of communicative disorders / Subhash C. Bhatnagar. —4th ed. p. ; cm. Includes bibliographical references and index. ISBN 978-1-60913-871-4 I. Title. [DNLM: 1. Central Nervous System—anatomy & histology. 2. Central Nervous System—physiology. 3. Communication Disorders—physiopathology. WL 300] 612.8—dc23 2011039961 DISCLAIMER Care has been taken to confirm the accuracy of the information present and to describe generally accepted practices. However, the authors, editors, and publisher are not responsible for errors or omis- sions or for any consequences from application of the information in this book and make no warranty, expressed or implied, with respect to the currency, completeness, or accuracy of the contents of the publication. Application of this information in a particular situation remains the professional respon- sibility of the practitioner; the clinical treatments described and recommended may not be considered absolute and universal recommendations. 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To purchase additional copies of this book, call our customer service department at (800) 638-3030 or fax orders to (301) 223-2320. International customers should call (301) 223-2300. Visit Lippincott Williams & Wilkins on the Internet: http://www.lww.com. Lippincott Williams & Wilkins customer service representatives are available from 8:30 am to 6:00 pm, EST. 9 8 7 6 5 4 3 2 1 BBhhaattnnaaggaarr__FFMM..iinndddd iiii 1122//11//22001111 66::0011::4499 PPMM The wealth of knowledge is the best of all possessions; it can neither be stolen, nor taken away by government, nor divided among brothers. It is never a burden to carry this wealth, which increases only by sharing and giving. —A Sanskrit Saying I dedicate this book to My late father Shri Chiranji Lal Bhatnagar, who did everything possible, and more, to nurture and inspire and My late friend, Dr. Orlando J. Andy, who m entored me on cognitive aspects of neurosurgery. BBhhaattnnaaggaarr__FFMM..iinndddd iiiiii 1122//11//22001111 66::0011::4499 PPMM Foreword Once again, it is my deep pleasure to write the tional use, film clips, a structure mapping brain atlas, and foreword for this latest edition of Subhash much more. Bhatnagar’s now classic text Neuroscience for the Study of Just as neuroscience and its study have advanced, so Communicative Disorders. I have been honored to write have the needs of students in Speech and Hearing Science. the previous three forewords as well. It is enlightening to At its heart, I believe that neuroscience is the cornerstone look back over those three earlier editions to note not of our profession and its clinical applications. Serious stu- only the increasing complexity of neuroscience as it is dents can no longer slip by with a superficial knowledge reflected therein but also to note the increasing sophisti- or a modest appreciation of the role that neuroscience cation, as well as the elegance with which Dr. Bhatnagar plays in their chosen profession. Neuroscience for the Study has made the subject, edition after edition, more acces- of Communication puts a sound foundation in that subject sible and user-friendly to students, teachers, and profes- at their fingertips and provides their instructors with sionals who should keep it always near them as a fine strong teaching tools to aid in the process. reference work. As neuroscience inevitably has advanced since the last Audrey L Holland, PhD edition 5 years ago, so has the technology of teaching. This Regents’ Professor Emerita volume takes advantage of these changes as well, with the The University of Arizona addition of a Web site, PowerPoint outlines for instruc- Tucson, Arizona iv BBhhaattnnaaggaarr__FFMM..iinndddd iivv 1122//11//22001111 66::0011::4499 PPMM Preface This genesis of this book is rooted in the growing rec- • Additional clinical details about the embryonic synapse ognition of the importance of neuroscience and its development and inherent cell loss (apoptosis) have relationship with cognitive–communicative functions. been reexamined from a cognitive–communicative This recognition has been furthered by the increasing perspective. emergence of a patient population with neurological con- • The section on neuroimaging has been rewritten, in ditions that includes roughly 50 million Americans, many conjunction with images, to address newer develop- with cognitive–communicative disorders (Castro et al., ments in the field of neuroimaging (functional MRI, 2002), an area of primary concern to clinicians working in diffusion-weighted MRI, perfusion-weighted MRI, dif- the field of human behavior. fusion tensor imaging, and MRI spectroscopy). • The sections on respiratory control and consciousness have been rewritten to include newer concepts. FEATURES AND ORGANIZATION • The enhanced list of medical abbreviations has been cat- egorized into practical categories, in order to increase The needs and challenges that provided the impetus for its utility, such as assessment, body part, chemical, dis- writing this book in the first place have not changed ease, hospital location, patient attribute, professional since its first edition went to print in 1995. This is now association, and treatment. the fourth edition in this continuing endeavor, which • The glossary has been enhanced and streamlined to was first envisioned by the late Dr. Orlando Andy and make it a more effective quick-reference resource. myself, to present the basics of neuroscience in a way To assist instructors, each chapter has been reorganized to that students could find both meaningful and interesting, allow easy access to and retrieval of pertinent information. while also giving academic faculty a tool for teaching the All of the chapters contain the following, uniform sections: foundations and exploring the complexities of neurosci- ence. In order to make the study of neuroscience further • Clinical considerations accessible and user-friendly, and to promote an analytic • Some have a section for lesion localizing rules and approach to learning and critical thinking, the following explanations. improvements have been made in this print: • Problem-solving case studies • Inclusion of case study discussions at the end of the • A large part of the book has been rewritten so that the book inherent, technical complexity of neuroscience is fur- • Section or chapter summary ther simplified, in part, by focusing on the applications • Review questions (for classroom quizzes) of theoretical and difficult concepts. • Inclusion of review question answers at the end of the • Approximately 35% of the images have been modified book to improve their effectiveness as a teaching and learning • The review questions and answers are written in such tool. a way that they can be programmed on software like • Approximately 22 new MR and CT images (both nor- D2L that would allow immediate feedback to the stu- mal and with pathologies) have been added to promote dents of their errors. the application of learning to brain imaging. • The text has been amended to include important clini- In addition, this edition has the following features: cal information in order to promote critical thinking, • Fully outlined text in each section to facilitate reorgani- including zation for an individually tailored teaching. • Approximately 60 boxes with clinical medical infor- • This outline allows the instructors to reorganize the mation information to meet their specific teaching needs. • Approximately 10 more summarizing tables • Development of about 500 multiple choice and clinical • Approximately 10 new, interactive problem-solving case study questions with answers. case studies • This resource with many images is available to the • Neurogenic concepts related to human c ommunication instructors on the book’s Web site. Students have • An updated discussion of cellular biology and neuroem- access to only questions. bryology is added. v BBhhaattnnaaggaarr__FFMM..iinndddd vv 1122//11//22001111 66::0011::4499 PPMM vi PREFACE • A Web site that contains a structure mapping brain atlas These instructor and student ancillaries can be found at and movie clips to be used for additional study http://www.thepoint.lww.com/Bhatnagar4e • A reorganized structure that sequences the circulatory Despite these efforts to simply the book to increase its system before the chapters dedicated to sensorimotor accessibility, the inherent complexity of neuroscience is physiology. maintained and appreciated in this book. It is my hope • This reorganization, based on the feedback received that these efforts at revision conform with Albert Einstein’s from other teachers, will allow students to apply their famous aphorism: “Make everything as simple as possible, knowledge of the vascular system to the sensorimotor but not simpler.” brain. • A developed PowerPoint outline of the book Subhash C. Bhatnagar BBhhaattnnaaggaarr__FFMM..iinndddd vvii 1122//11//22001111 66::0011::4499 PPMM Acknowledgments At the outset, I wish to thank my many colleagues and Obviously this book would not have been possible students around the country, who have provided me without the support of many at Wolters Kluwer/Lippincott with invaluable feedback about their experience with prior Williams and Wilkins. I express my thanks to Peter editions of this book. Their input has resulted in the addi- Sabatini and Julie Stegman (editors), Timothy Serpico tion of important information and improved the presenta- (marketing manager), and John Larkin (product man- tion of existing material, while keeping the study of ager). I also thank Jennifer Clements for her hard work in neuroscience clear and accessible. preparing the artwork for the book. In preparing this edition of the book, I am grateful to I am especially grateful to Dr. Audrey L. Holland from many of my colleagues for their time, energy, and support. the University of Arizona for agreeing to write the foreword These colleagues, without whom this edition would not be of this edition, just as she has for the prior three editions of possible, include Dr. Duane E. Haines, University of this book. It has been my honor to have her support and Mississippi Medical Center; Dr. Robin L. Curtis (retired), ongoing friendship from my days as a graduate student. Medical College of Wisconsin; Dr. Alexandru Barboi, I also thank Ms. Martha Jerme, the health sciences Medical College of Wisconsin; Dr. Lotfi Hacein-Bey, librarian from Marquette University, for her invaluable assis- Radiological Associates of Sacramento Medical Group Inc; tance in ensuring all references in this edition are up-to-date. Dr. Satish Jain, Indian Epilepsy Center, New Delhi; Dr. I am indebted to my many students at Marquette Howard Kirshner, Vanderbilt College of Medicine; Dr. University, whose comments and feedback over the years Madhuri Behari, All India Institute of Medical Sciences, in the classroom have been both invaluable and encourag- New Delhi; Dr. William Mustain, University of Mississippi ing. I am particularly thankful to three of my graduate stu- Medical Center, Milwaukee; Dr. Varun Saxena, Center for dents—Libby Kelley, Bridget Zmolek, and Amy Spilsky, Neurological Disorders; Dr. Kunwar Bhatnagar, University each of whom has worked in my Neurolinguistics Lab and of Louisville College of Medicine; Dr. Sanjeev Pradhan, has diligently helped prepare many aspects of this edition. University of Illinois Medical Center; Dr. Michelle I also thank Kathryn Errek and Caitlin Fitzgerald for their Mynlieff, Marquette University; and Dr. Hugh Buckingham, help in preparing the PowerPoint for the book. Louisiana State University. I also thank Dr. Lotfi Hacein- Finally, I thank Priti, my wife and my best friend. Bey for jointly writing the ‘Neuroradiology section’. Without her understanding, support, and sacrifices, nei- I also acknowledge the help that I received from ther this edition nor any of the three that preceded it Dr. Alexandru Barboi for jointly writing the clinical ques- would have been possible. I also thank my children— tions for ‘ThePoint,’ the website that accompanies this Manav, Gaurav, and Kathryn—whose emotional support book. and encouragement underlies everything I do. vii BBhhaattnnaaggaarr__FFMM..iinndddd vviiii 1122//11//22001111 66::0011::4499 PPMM Contents Foreword iv Preface v Acknowledgments vii C HAPTE R 1 Forebrain in Coronal Sections. . . . . . . . . . . . . . . . . . . . . . . . . . 115 Forebrain in Horizontal Sections. . . . . . . . . . . . . . . . . . . . . . . . 123 Essential Neurological Concepts and Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Principles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Relationship Between Neuroscience and Speech– Language–Hearing Pathology . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 C HAPTE R 4 Scope of Neuroscience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Development of the Nervous Principles Governing the Human Brain . . . . . . . . . . . . . . . . . . . . 7 System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .133 Orientation to Technical Terminology . . . . . . . . . . . . . . . . . . . . 10 Human Chromosomes, Genes, and Cell Division . . . . . . . . . . 133 Structures of the CNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Early Human Development. . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 Nervous System Classification . . . . . . . . . . . . . . . . . . . . . . . . . . 18 The Central Nervous System. . . . . . . . . . . . . . . . . . . . . . . . . . . 138 Cellular Cortex. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 The Peripheral Nervous System . . . . . . . . . . . . . . . . . . . . . . . . 142 Techniques for Learning Neuroscience . . . . . . . . . . . . . . . . . . . 22 Clinical Correlates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 Clinical Correlates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 C HAPTE R 5 C HAPTE R 2 Nerve Cell Physiology . . . . . . . . . . . . . . . . . . .152 Gross Anatomy of the Central Nervous Neuron. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35 Central and Peripheral Nervous Systems. . . . . . . . . . . . . . . . . 157 Central and Peripheral Nervous Systems. . . . . . . . . . . . . . . . . . 35 Neuronal Pruning and Synapse Establishment . . . . . . . . . . . . 157 Primary Divisions of the Brain . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Nerve Impulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Anatomy of the Brain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Neuronal Responses to Brain Injuries . . . . . . . . . . . . . . . . . . . 161 Ventricles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Neurotransmitters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 Cortical White Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Clinical Correlates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 Meninges of the Brain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Meninges of the Spinal Cord . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Cranial Nerves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 C HAPTE R 6 Autonomic Nervous System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 Diencephalon: Thalamus and Associated Clinical Correlates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Structures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Gross Anatomy of the Diencephalon. . . . . . . . . . . . . . . . . . . . 175 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Thalamus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 C HAPTE R 3 Epithalamus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 Subthalamus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 Internal Anatomy of the Central Nervous Hypothalamus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182 System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95 Cognitive Functions of the Thalamus. . . . . . . . . . . . . . . . . . . . 183 Anatomical Landmarks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Clinical Correlates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 Spinal Cord in Cross Sections. . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 Brainstem in Transverse Sections. . . . . . . . . . . . . . . . . . . . . . . 100 Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185 viii BBhhaattnnaaggaarr__FFMM..iinndddd vviiiiii 1122//11//22001111 66::0011::4499 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