The Private Life of the Brain: Emotions, Consciousness, and the Secret of the Self

236 Pages·2001·1.47 MB·English

by  Susan A. Greenfield

PENGUIN BOOKS
THE PRIVATE LIFE OF THE BRAIN
Susan A. Greenfield is a leading neuroscientist based at the Department of Pharmacology, Oxford. She is the Director of the Royal Institution of Great Britain and is the author of Mindwaves, Journey to
the Centres of the Mind and The Human Brain: A Guided Tour. She presented a six-part television series on the brain, called Brainstory, for BBC2, and is author of the accompanying book of the same
name. She is an Honorary Fellow of the Royal College of Physicians. In 2000 she was awarded a CBE and a Life Peerage in 2001.
THE PRIVATE LIFE OF THE BRAIN
Susan Greenfield
PENGUIN BOOKS
PENGUIN BOOKS
Published by the Penguin Group
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First published simultaneously in the USA and Canada
by John Wiley & Sons, Inc. 2000
First published in Great Britain by Allen Lane The Penguin Press 2000
Published in Penguin Books 2001
Reissued 2002
12
Copyright © Susan Greenfield, 2000
All rights reserved
The moral right of the author has been asserted
Except in the United States of America, this book is sold subject to the condition that it shall not, by way of trade or otherwise, be lent,re-sold, hired out, or otherwise circulated without the publisher’s
prior consent in any form of binding or cover other than that in which it is published and without a similar condition including this condition being imposed on the subsequent purchaser
ISBN: 978-0-14-193787
For
David Brynmor Thomas
C
ONTENTS
Preface
1 The Idea
2 The Story So Far
3 The Child
4 The Junkie
5 The Nightmare
6 The Depressive
7 The Human Condition
8 The Answer?
Appendix: The Reality of a Neural Correlate of Consciousness
Notes
Bibliography
Index
P
REFACE
This book initially started life as a neuroscientist’s exploration of pleasure. I was
fascinated by what motivated so many of my colleagues and friends to work
hard, to accrue money, and to invest long hours in a library or office, when
instead they could simply have been sitting in the sun or enjoying a good claret.
Obviously, they needed to survive and feed and clothe their children, but many
of us in Western society can achieve those goals without working the long hours
that many do. And the price paid seemed crazy. You have only to look at
children splashing in a paddling pool, and in general living for the moment, to
feel that one has, perhaps, lost the plot. What has actually happened in the brain?
The human condition seems to entail an uneasy vying between times of
abandonment when we “let ourselves go” and other times—most of the time, in
fact—when we are “developing” or “broadening” our minds, where above all,
we have a strong sense of ourselves and some partial control, at least, over what
is happening around us. The more I tried to translate into brain terms this
dichotomy between the sensual, momentary existence and the self-conscious
adult human mind-set, the more I realized that it did not apply to pleasure alone,
but to a far wider range of basic emotions. Hence the quest for a
neurophysiology of pleasure widened into a consideration of all the emotions,
both how the brain can accommodate their diversity, as well as whether there
might be a common basic factor that distinguishes an emotion, in general, as
such. My “solution” as you will see, is that emotions and the mind are not stark
polar opposites, but rather the ends of a continuum.
In order to match up what we feel to greater or lesser extents at any time with
what is going on in the brain, I was thankful for my earlier training in
neuropharmacology; it seemed to me that drugs offered the perfect Rosetta
Stone, a bridge, for relating two sets of phenomena, one objective (physical
events in the brain), the other subjective (what you are feeling), that normally are
hard to link up with each other. Nonetheless, by looking at various conditions
resulting from the use of both prescribed and proscribed drugs, it seems possible
to work out a more general scheme for the human condition and how it unfolds
from one moment to the next in the brain. Yet such a journey inevitably leads us
to the most challenging question of all: How does the brain generate the
firsthand experience of feeling, of consciousness?
I do not presume to have come up with The Answer here, but in the final
chapter, I do offer some thoughts that I hope will make a contribution to the
debate. Having suggested a theory in my earlier book Journey to the Centers of
the Mind, I have now been able to develop the basic idea that consciousness
varies in degrees that are correlated with highly evanescent assemblies of
neurons. The final chapter outlines the different factors that govern formation of
these assemblies, and describes how in turn their configuration and size in the
physical brain indicate different states of mind. Finally, we turn to the important
issue, often overlooked by neuroscientists, that brain functioning must always be
seen as an integral part of the whole body: I suggest a means whereby the brain
and body function in concert and argue that it is the iteration between body and
brain that is consciousness. For those with a taste for the technical, the Appendix
offers a more detailed, physiological account of the scheme.
The basic message of this book is that emotions such as pleasure necessitate a
temporary abrogation of the self, the individual carefully developed throughout a
lifetime. Perhaps this is an idea that has long lurked in our folklore, captured in
expressions such as “blowing the mind,” but which is now rooted here in the
physical brain. As such, I hope this book may provide some more insight into
why and how we do what we do for pleasure or otherwise.
Many people have helped bring the manuscript to fruition. First are my
editors, Emily Loose at Wiley and Stefan McGrath at Penguin, who have seen
the text through various incarnations and who have given invaluable advice. In
addition, my agents, John Brockman and Katinka Matson, should be thanked for
their unstinting support and help. I am also very grateful to the following
colleagues for helping with endless queries: Henry Marsh, Nick Rawlins, Ole
Paulsen, Kim Jobst. But above all, I wish to acknowledge my husband, Peter, for
providing continued support, advice, and encouragement, and without whom I
would never have been able to have even started this project.
This book is dedicated to David Brynmor Thomas. I first met David in 1996,
when he was supposed to have retired but was acting head of the technology
transfer unit of Oxford University. My colleague David Vaux and I were filing a
patent and were interested in starting a biotech company as a consequence.
Without David Thomas’s flair, humor, imagination, and courage, we would
never have gotten past first base. Just as the company, Synaptica—where he
ended up as Secretary—was starting to flourish, David tragically developed a
fast-growing cancer and died within a few months, in May 1999. Both David
Vaux and I feel his loss keenly, not only as a valued mentor professionally, but
also as someone who came to be a very close friend. This book is not about
companies nor technology transfer, but I hope David would have liked it.
Susan Greenfield
Oxford
October 1999