This title is also available as an e-book.
For more details, please see
www.wiley.com/buy/9781119168416
This edition first published 2018
© 2018 John Wiley & Sons Ltd.
Edition History
Fourth edition published 2012 © 2012 by John Wiley & Sons, Ltd.
Third edition © 2008 Roger Barker and Stephen Barasi.
Second edition © 2003 Roger Barker and Stephen Barasi.
First edition © 1999 Roger Barker and Stephen Barasi.
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, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions.
The right of Roger A. Barker, Francesca Cicchetti and Emma S.J. Robinson to be identified as the authors of this work has been asserted in accordance with law.
Registered Offices
John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA
John Wiley & Sons, Ltd. The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK
Editorial Office
9600 Garsington Road, Oxford, OX4 2DQ, UK
For details of our global editorial offices, customer services, and more information about Wiley products visit us at www.wiley.com.
Wiley also publishes its books in a variety of electronic formats and by print-on-demand. Some content that appears in standard print versions of this book may not be available in other formats.
Limit of Liability/Disclaimer of Warranty
The contents of this work are intended to further general scientific research, understanding, and discussion only and are not intended and should not be relied upon as recommending or promoting scientific method, diagnosis, or treatment by physicians for any particular patient. In view of ongoing research, equipment modifications, changes in governmental regulations, and the constant flow of information relating to the use of medicines, equipment, and devices, the reader is urged to review and evaluate the information provided in the package insert or instructions for each medicine, equipment, or device for, among other things, any changes in the instructions or indication of usage and for added warnings and precautions. While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials or promotional statements for this work. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.
Library of Congress Cataloging-in-Publication Data
Names: Barker, Roger A., 1961- author. | Cicchetti, Francesca, author. |
Robinson, Emma S. J., 1974- author.
Title: Neuroanatomy and neuroscience at a glance / Roger A. Barker, Francesca
Cicchetti, and Emma S.J. Robinson.
Description: Fifth edition. | Hoboken, NJ : Wiley, 2017. | Series: At a
glance | Includes bibliographical references and index. |
Identifiers: LCCN 2017012665 (print) | LCCN 2017014341 (ebook) | ISBN
9781119168430 (pdf) | ISBN 9781119168423 (epub) | ISBN 9781119168416 (pbk.)
Subjects: | MESH: Nervous System Physiological Phenomena | Nervous
System—anatomy & histology | Nervous System Diseases
Classification: LCC RC341 (ebook) | LCC RC341 (print) | NLM WL 102 | DDC
616.8—dc23
LC record available at https://lccn.loc.gov/2017012665
John Wiley & Sons Limited is a private limited company registered in England with registered number 641132. Registered office address: The Atrium, Southern Gate, Chichester, West Sussex, United Kingdom. PO19 8SQ.
Cover image: ©SEBASTIAN KAULITZKI/SCIENCE PHOTO LIBRARY/Gettyimages
This book is dedicated to Imogen Rose Barker,
who died tragically in February 2007: a wonderful
daughter and an inspiration to many.
Neuroanatomy and Neuroscience at a Glance is designed primarily for medical students as a revision text or review of basic neuroscience mechanisms, rather than a comprehensive account of the field of medical neuroscience. The book does not attempt to provide a systematic review of clinical neurology, although one of the new features of the fourth edition was the introduction of more clinical cases to illustrate how neurology builds on a good knowledge of basic neuroscience. In addition, the changing nature of medical training has meant that rather than teaching being discipline-based (anatomy, physiology, pharmacology, etc.), the current approach is much more integrated with the focus on the entire system. Students pursuing a problem-based learning course will also benefit from the concise presentation of integrated material.
This book summarizes the rapidly expanding field of neuroscience with reference to clinical disorders, such that the material is set in a clinical context with the later chapters being more clinically oriented. However, learning about the organization of the nervous system purely from clinical disorders is short-sighted as the changing nature of medical neuroscience means that areas with little clinical relevance today may become more of an issue in the future. An example of this is ion channels and the recent burgeoning of a host of neurological disorders secondary to a channelopathy. For this reason, some chapters focus more on scientific mechanisms with less clinical emphasis.
Each chapter presents the bulk of its information in the form of an annotated figure, which is expanded in the accompanying text. It is recommended that the figure is worked through with the text rather than just viewed in isolation. The condensed nature of each chapter means that much of the information has to be given in a didactic fashion. Although the text focuses on core material, some additional important details are also included.
The book is structured such that it begins with the anatomical and functional organization of the nervous system (Chapters 1–11); the cells of the nervous system and how they work (Chapters 12–21); the sensory components of the nervous system (Chapters 22–34); the motor components of the nervous system (Chapters 35–42); the autonomic, limbic and brainstem systems underlying wakefulness and sleep along with neural plasticity and a new chapter on techniques to study the nervous system in the lab (Chapters 43–49); and, finally, a section on the approach, investigation and range of clinical disorders of the nervous system (Chapters 50–65).
Each section builds on the previous ones to some extent, and so reading the introductory chapter may give a greater understanding to later chapters in that section; for example, the somatosensory system chapter (Chapter 31) may be better read after the chapter on the general organization of sensory systems (Chapter 22).
In this latest edition of the book we have attempted to further integrate the clinical relevance of neurobiology into the text and website and brought in a new author to help with the neuropharmacological developments in central nervous system disease, Dr Emma Robinson. We have continued and updated our ‘Did you know?' section at the end of each chapter while Part 7 consists of relevant clinical scenarios for each chapter along with questions and answers. The companion website has key revision points and multiple-choice questions relating to the content of each chapter.
We hope that you find this new edition of the book a useful accompaniment to your studies from undergraduate to post-graduate to clinical level.
Roger A. Barker
Cambridge
Francesca Cicchetti
Quebec
Emma S. J. Robinson
Bristol
We would like to thank all the students that we have taught over the years who have helped us refine this book as well as the team at Wiley-Blackwell for all their help and innovative ideas in this new, more colourful edition of the book.
Chapters
The first signs of nervous system development occur in the third week of gestation, under the influence of secreted factors from the notochord, with the formation of a neural plate along the dorsal aspect of the embryo. This plate broadens, folds (forming the neural groove) and fuses to form the neural tube, which ultimately gives rise to the brain at its rostral end (i.e. towards the head) and the spinal cord caudally (i.e. towards the feet/tail). The fusion begins approximately halfway along the neural groove at the level of the fourth somite and continues caudally and rostrally with the closure of the posterior/caudal and anterior/rostral neuropore during the fourth week of gestation.
The process of neural tube fusion isolates a group of cells termed the neural crest.
The neural tube surrounds the neural canal, which forms the central canal of the fully developed spinal cord.
The cerebral cortex develops in a ‘radial unit’ manner, with radial glial cell precursor cells from the ventricular zone of the emerging cerebral hemispheres (see Chapter 10). Those neurones born from the ventricular zone (VZ) give rise to the neurones in the deep layers of the cerebral cortex, while the cells from the subventricular zone (SVZ) form the more superficial layers of the cortex. The developing cortex then folds into gyri and sulci and specification into distinct cortical areas. Of late, the genes driving all these processes have been identified as have the physical rules which are employed to allow the growing brain to fold in this way. The radial glial cells that help guide the newborn cells to the developing cortex give rise to the white matter (see Chapter 2).
Until recently it was believed that no new neurones could be born in the adult mammalian brain. However, it is now clear that neural progenitor cells can be found in the adult CNS, including in humans. These cells are predominantly found in the dentate gyrus of the hippocampus (see Chapter 45) and just next to the lateral ventricles in the subventricular zone (SVZ). They may also exist at other sites of the adult CNS but this is contentious. They respond to a number of signals and appear to give rise to functional neurones in the hippocampus and olfactory bulb, with the latter cells migrating from the SVZ to the olfactory bulb via the rostral migratory stream (RMS). They may therefore fulfil a role in certain forms of memory and possibly in mediating the therapeutic effects of some drugs such as antidepressants (see Chapter 57).
The nervous system can be divided into three major parts: the autonomic (ANS), peripheral (PNS) and central (CNS) nervous systems. The PNS is defined as those nerves that lie outside the brain, brainstem or spinal cord, while the CNS embraces those cells that lie within these structures.
The autonomic nervous system (ANS) includes those nerve cells and fibres that innervate internal and glandular organs. They subserve the regulation of processes that usually are not under voluntary influence.
The CNS control of the ANS is complex, involving a number of brainstem structures as well as the hypothalamus (see Chapter 11). The main hypothalamic areas involved in the control of the ANS are the ventromedial hypothalamic area in the case of the sympathetic nervous system and the lateral hypothalamic area in the case of the parasympathetic nervous system. Controlling pathways are direct or indirect via a number of brainstem structures such as the periaqueductal grey matter and parts of the reticular formation (see Chapter 8).
Damage to the ANS can either be local to a given anatomical structure, or generalized when there is loss of the whole system caused by either a central or peripheral disease process.
In all these cases the patient presents with orthostatic and postprandial hypotension (syncopal or presyncopal symptoms on standing, exercising or eating a big meal) with a loss of variation in heart rate, bowel and bladder disturbances (urinary urgency, frequency and incontinence), impotence, loss of sweating and pupillary responses. The symptoms are often difficult to treat and a number of agents are used to try to improve the postural hypotension and sphincter abnormalities. Agents for postural hypotension include fludrocortisone, ephedrine, domperidone, midodrine and vasopressin analogues (all of which cause fluid retention).
The enteric nervous system (ENS) is found in the wall of the gut, primarily the small and large intestine, and is involved with normal gastrointestinal motility and secretory functions. It contains more than 100 million nerve cell bodies and supporting glial cells. It is heavily innervated and regulated by the autonomic nervous system, but is a separate entity with its own intrinsic circuitry and function. It has no major role in the oesophagus and it is less clear what role it fulfils in the stomach.
The ENS consists of two plexuses:
The plexuses consist of:
Multiple neurotransmitters and receptors are found in the different neuronal populations, the activities of which can therefore be modulated by a large number of drugs as well as by the autonomic nervous system. Many of the neurones of the ENS contain more than one neurotransmitter.