Table Of ContentThe
Other Brain
FROM DEMENTIA TO SCHIZOPHRENIA,
HOW NEW DISCOVERIES ABOUT THE BRAIN ARE
REVOLUTIONIZING MEDICINE AND SCIENCE
R. D F , P .D.
OUGLAS IELDS H
Simon & Schuster
1230 Avenue of the Americas
New York, NY 10020
www.SimonandSuster.com
Copyright © 2009 by R. Douglas Fields
All rights reserved, including the right to reproduce this book or portions thereof
in any form whatsoever. For information address Simon & Schuster Subsidiary
Rights Department, 1230 Avenue of the Americas, New York, NY 10020.
First Simon & Schuster hardcover edition January 2010
SIMON & SCHUSTER and colophon are registered trademarks of Simon &
Schuster, Inc.
Figure credits are listed after the Index.
For information about special discounts for bulk purchases, please contact
Simon & Schuster Special Sales at 1-866-506-1949 or
[email protected].
The Simon & Schuster Speakers Bureau can bring authors to your live event. For
more information or to book an event contact the Simon & Schuster Speakers
Bureau at 1-866-248-3049 or visit our website at www.simonspeakers.com.
DESIGNED BY Kyoko Watanabe Manufactured in the United States of America
1 3 5 7 9 10 8 6 4 2
Library of Congress Cataloging-in-Publication Data Fields, R. Douglas.
The other brain : from dementia to schizophrenia, how new discoveries about the
brain are revolutionizing medicine and science / R. Douglas Fields.
p. cm.
Includes bibliographical references and index.
1. Brain—Physiology. 2. Brain chemistry. 3. Cognitive neuroscience. I. Title.
QP376.F46 2009
612.8—dc22 2009034287
ISBN 978-0-7432-9141-5
ISBN 978-1-4391-6043-5 (ebook)
C
ONTENTS
PREFACE
ACKNOWLEDGMENTS
PART I
Discovering the Other Brain
CHAPTER 1: Bubble Wrap or Brilliant Glue?
CHAPTER 2: A Look Inside the Brain: The Cellular Components of the Brain
CHAPTER 3: Transmissions from the Other Brain: Glia Know and Control Your
Mind
PART II
Glia in Health and Disease
Mending the Mind: Glia Repairing Nervous System Damage and Disease
CHAPTER 4: Brain Cancer: Almost Nothing to Do with Neurons
CHAPTER 5: Brain and Spinal Cord Injury
CHAPTER 6: Infection
CHAPTER 7: Mental Health: Glia, Silent Partners in Mental Illness
CHAPTER 8: Neurodegenerative Disorders
CHAPTER 9: Glia and Pain: A Blessing and a Curse
CHAPTER 10: Glia and Addiction: A Neuron-Glia Dependence
CHAPTER 11: Mother and Child
CHAPTER 12: Aging: Glia Rage against the Dying Light
PART III
Glia in Thought and Memory
CHAPTER 13: The Mind of the Other Brain: Glia Controlling the Conscious and
Unconscious Mind
CHAPTER 14: Memory and Brain Power beyond Neurons
CHAPTER 15: Thinking beyond Synapses
CHAPTER 16: Into the Future: The New Brain
GLOSSARY
NOTES
BIBLIOGRAPHY
INDEX
P
REFACE
How do the 100 billion neurons in our brain allow us to remember who we are;
to learn, think, and dream; to be stirred by passion or rage; to ride a bike or
conjure meaning from inked patterns on paper; or to pluck out instantly a
mother’s voice from the muddle of a noisy crowd? What goes wrong with neural
circuits in schizophrenia or depression, or in dreadful diseases like Alzheimer’s,
multiple sclerosis, chronic pain, or paralysis?
We are on the cusp of a new understanding of the brain that transforms a
century of conventional thinking about the brain, specifically the role of the
brain’s neurons. Crowding around the computer screen in a darkened room in
1990, scientists watched information passing through peculiar brain cells,
bypassing neurons and communicating without using electrical impulses. Until
this discovery scientists had presumed that information in the brain flowed only
through neurons by using electricity. In fact, a mere 15 percent of the cells in our
brain are neurons. The rest of our brain cells—called glia—have been
overlooked as little more than packing material stuffed between the electric
neurons. “Housekeeping cells” they were called. Dismissed as cellular domestic
servants, glia were neglected for more than a century after they were discovered.
Now scientists are shocked to learn that these odd brain cells communicate
among themselves. Scientists’ understanding of the brain has been shaken to its
foundation by the discovery that these cells not only sense electrical activity
flowing through neural circuits—they can control it.
How did scientists miss half the brain until now? Glia do not fire electrical
impulses, and so the probing electrodes neuroscientists use to monitor neurons
were deaf to glial transmissions. Glia are not connected through synapses into
circuits the way neurons are. Rather than passing messages sequentially like a
falling line of dominos, glia broadcast their messages broadly throughout the
brain.
How will this new discovery change our understanding of the mind? Will the
mysteries of how the mind fails in mental illness or disease be solved as we
explore this new dimension of the brain? Will the search uncover answers to
how the brain can be repaired after disease or injury?
The discovery of glia—the other brain—is a dawning that illuminates every
aspect of brain science, touching simultaneously all researchers working on the
brain. This is a story of science in action, with twists and turns, insight and
confusion, controversy and consensus. Along the way you will meet some
fascinating scientists who are real people, each one different and sometimes
peculiar, but each engaged in the most collaborative of all human activities—
science.
The information here is so new it has not yet found its way into textbooks.
This information will change your understanding of the brain. It will also
provide you essential knowledge that will benefit you or your loved ones in your
own health. The book is packed with the latest information on neuroscience and
medicine, and it brings you inside for an eyewitness view through the eyes of
one of the researchers involved.
A
CKNOWLEDGMENTS
Although I had written many academic articles on this subject, this book
originated when the editors at Scientific American, Ricki Rusting and John
Rennie, were intrigued enough to publish an article submitted by an unknown
author. At a time when the information was new and strange, and still discounted
by many, they appreciated the importance of this breakthrough and published the
first article on glia for a popular audience as the cover story of the April 2004
issue, “The Other Half of the Brain.” I owe much of the success of that article to
the editor who worked with me on it, Mark Fischetti.
It might have ended there had not Jeff Kellogg, a literary agent who read the
Scientific American article, contacted me with the suggestion that I write a book
on the subject. Knowing nothing of literary agents or book writing for the
popular market, I promptly deleted his e-mail—and his next one as well.
Fortunately he persisted, and soon I learned from Jeff how to write a book
proposal. I could not have had a better person helping me and working as my
agent. When Simon & Schuster agreed to publish the book, the difficult task of
guiding a research scientist through the complex process of writing a book that
the public might want to read fell to Senior Editor Bob Bender. Bob’s expert
guidance has been crucial in bringing this book to completion, and I am grateful
for his help and commitment to the project. I am indebted to Loretta Denner, to
Amy Ryan for her discerning copyediting, to Morgan Ryan for careful fact-
checking, and to Johanna Li.
To all my scientific colleagues and coworkers who permitted me to share their
stories and comments, I offer my sincere thanks. I hope that the reading will
provide for them, as the writing did for me, a renewed appreciation of the joy
and privilege of what we do as scientists. I owe a special thanks to Dr. Susanne
Zimmermann and Prof. Christoph Redies of the University of Jena for their help
in researching Hans Berger, and to Lydia Kibiuk, Alan Hoofring, and Jen
Christiansen for their outstanding illustrations.
One of the delights of this project has been working with and learning from
some of the top editors and authors bringing science to the public. In particular I
acknowledge Mariette DiChristina, Christine Soares, and David Dobbs at
Description:Despite everything that has been written about the brain, a potentially critical part of this vital organ has been overlooked—until now. The Other Brain examines the growing importance of glia, which make up approximately 85 percent of the cells in the brain, and the role they play in how the brai
