Copyright © 2014 by D. F. Swaab
All rights reserved.
Published in the United States by Spiegel & Grau, an imprint of Random House, a division of Random House LLC, a Penguin Random House Company, New York.
SPIEGEL & GRAU and the HOUSE colophon are registered trademarks of Random House LLC.
The publisher gratefully acknowledges the support of the Dutch Foundation for Literature.
Library of Congress Cataloging-in-Publication Data
Swaab, D. F. (Dick Frans)
We are our brains: a neurobiography of the brain, from the womb to Alzheimer’s / D. F. Swaab ; translated by Jane Hedley-Prôle.
pages cm
ISBN 978-0-8129-9296-0
eBook ISBN 978-0-679-64437-8
1. Brain. 2. Brain—Research. 3. Neurosciences. I. Title.
QP376.S858 2014
612.8′2—dc23 2013020412
www.spiegelandgrau.com
Jacket design: Thomas Ng
Jacket image (silhouette of child): © Cut Arts, Inc.
v3.1
Contents
Cover
Title Page
Copyright
LIST OF ILLUSTRATIONS
EPIGRAPH
PREFACE
INTRODUCTION
We Are Our Brains
Metaphors for the Brain
1. DEVELOPMENT, BIRTH, AND PARENTAL CARE
The Subtle Interaction Between Mother and Child at Birth
A Difficult Birth as the First Symptom of a Developmental Brain Disorder
Maternal Behavior
Paternal Behavior
The Importance of a Stimulating Environment for Early Brain Development
Memories from the Womb
2. THREATS TO THE FETAL BRAIN IN THE “SAFETY” OF THE WOMB
Developmental Brain Disorders Caused by Environmental Factors
Developmental Brain Disorders Caused by Addictive Substances and Medication
The Short-Term Outlook of the Unborn Child
Does a Fetus Feel Pain?
Sawing Off Your Own Leg: Body Integrity Identity Disorder, a Bizarre Developmental Disorder
3. SEXUAL DIFFERENTIATION OF THE BRAIN IN THE WOMB
A Typical Boy or Girl?
Gender-Based Differences in Behavior
Heterosexuality, Homosexuality, and Bisexuality
Homosexuality: No Choice
Homosexuality in the Animal Kingdom
Transsexuality
Pedophilia
Public Response to My Research into Sex Differences in the Brain
Checking the Pope’s Sex
4. PUBERTY, LOVE, AND SEXUAL BEHAVIOR
The Adolescent Brain
Adolescent Behavior
The Brain in Love
Disorders of the Brain and Sexuality
5. HYPOTHALAMUS: SURVIVAL, HORMONES, AND EMOTIONS
Hormone Production by the Hypothalamus and Streams of Urine
Surviving Without a Hypothalamus
Depression
Prader-Willi Syndrome
Obesity
Cluster Headache
Narcolepsy: Weak with Laughter
Fits of Laughter Without Emotion
Anorexia Nervosa Is a Disease of the Brain
6. ADDICTIVE SUBSTANCES
Cannabis and Psychoses
Ecstasy: Brain Damage After Pleasure
Substance Abuse by Politicians
7. THE BRAIN AND CONSCIOUSNESS
Neglect: Half a Life
Coma and Related Conditions
Brain Structures Crucial for Consciousness
The Importance of Functional Links Between Brain Structures for Consciousness
Illusions and Loss of Self-Consciousness
“Filling In” Missing Information
Notions About the Mechanisms of Consciousness
8. AGGRESSION
Born Aggressive
Young and Aggressive
Aggression, Brain Disorders, and Prison
Guilt and Punishment
Violent While Asleep
9. AUTISM
Daniel Tammet, an Autistic Savant
Autism, a Developmental Disorder
Savants
Brains of Savants
10. SCHIZOPHRENIA AND OTHER REASONS FOR HALLUCINATIONS
Schizophrenia, a Disease of All Ages and Cultures
Schizophrenia Symptoms
Schizophrenia, a Developmental Brain Disorder
Hallucinations Due to a Lack of Stimuli
Other Hallucinations
11. REPAIR AND ELECTRIC STIMULATION
Age-Related Blindness: Macular Degeneration
Serendipity: A Lucky Accident
Deep Brain Stimulation
Brain Stimulation and Happiness
Prostheses in the Brain
Transplantation of Fetal Brain Tissue
Gene Therapy
Spontaneous Repair of Brain Damage
12. THE BRAIN AND SPORTS
Neuropornography: Boxing
Sex and the Olympic Games
Death of the Fittest
13. MORAL BEHAVIOR
Prefrontal Cortex: Initiative, Planning, Speech, Personality, and Moral Behavior
Moral Behavior: The Human in the Animal
Unconscious Moral Behavior
Moral Networks
What Nature Teaches Us About a Better Society
14. MEMORY
Kandel’s Research into Memory and the Collective Amnesia of the Austrians
The Anatomy of Memory
The Path to Long-Term Memory
Separate Memory Storage
The Implicit Memory in the Cerebellum
15. NEUROTHEOLOGY: THE BRAIN AND RELIGION
Why Are So Many People Religious?
The Evolutionary Advantage of Religion
The Religious Brain
A Better World Without Religion?
Unclean Mussels and Women
Praying for Another: A Placebo for Yourself
Religious Mania
Temporal Lobe Epilepsy: Messages from God
Public Reactions to My Views on Religion
16. THERE ISN’T MORE BETWEEN HEAVEN AND EARTH …
Soul Versus Mind
Heart and Soul
Pseudoscientific Explanations of Near-Death Experiences
Effective Placebos
Traditional Chinese Medicine: Sometimes More Than a Placebo
Herbal Therapy
17. FREE WILL, A PLEASANT ILLUSION
Free Will Versus Choice
The Brain as a Giant, Unconscious Computer
The Unconscious Will
What Free Will Isn’t
Free Will and Brain Disorders
18. ALZHEIMER’S DISEASE
Aging of the Brain, Alzheimer’s Disease, and Other Forms of Dementia
Alzheimer’s: The Stages of Deterioration
“Use It or Lose It”: Reactivating Neurons in Alzheimer’s Disease
Pain and Dementia
Alzheimer’s and the Right Moment for Choosing to End One’s Life
19. DEATH
The Magic of Life and Death
Dr. Deijman and Black Jan
Civic Disintegration Course: Dead Obvious
Netherlands Brain Bank
Herbs for Long Life After Death
20. EVOLUTION
Negotiation and Increase in Brain Size
The Evolution of the Brain
Molecular Evolution
Why a Week?
21. CONCLUSIONS
Dedication
Acknowledgments
About the Author
About the Translator
Illustrations
1. The br
ain seen from the side, with the parts of the cerebral cortex labeled.
2. Cross section of the brain.
3. Starting the birth process.
4. An anencephalic newborn.
5. The localization of oxytocin and vasopressin in the brain.
6. A synapse as seen under an electron microscope.
7. Brain scans of two three-year-old children, one who was brought up normally and one who was severely neglected.
8. Broca’s area and Wernicke’s area.
9. A child born in Amsterdam’s Wilhelmina Gasthuis hospital during the famine of 1944–1945.
10. The bed nucleus of the stria terminalis (BSTc), a region of the brain important for sexual behavior.
11. Comparing the bed nucleus of the stria terminalis in men, women, and transsexuals.
12. Postcard received after the author published the first findings of a difference between the brains of homosexual and heterosexual men, in 1989.
13. Another item of correspondence received after the author published the first findings of the difference between the brains of homosexual and heterosexual men.
14. Cartoon by Peter van Straaten after the publication of the first findings of the difference between the brains of homosexual and heterosexual men (1989).
15. The prefrontal cortex (PFC) as seen from the side.
16. The dopaminergic reward system.
17. Psychogenic erections and the passage of erotic impulses.
18. The human hypothalamus.
19. Narcolepsy.
20. The cerebral cortex, the thalamus, and the white matter.
21. The brain seen from below.
22. Some specialized cortical areas.
23. A depth electrode in the subthalamic nucleus of the brain of a Parkinson’s patient.
24. Effect of Parkinson’s disease on the motor area.
25. The basal nuclei and acetylcholine.
26. The route taken by information on its way to long-term memory.
27. Some brain systems involved in emotions.
28. The angular gyrus.
29. The two types of lesions associated with Alzheimer’s.
30. Brain shrinkage in frontotemporal dementia.
31. A patient in the final stage of Alzheimer’s.
32. Atrophy of the cerebral cortex in Alzheimer’s.
33. Atrophied neurons in the nucleus basalis of Meynert.
34. Slices of tissue from the brain of a patient with Alzheimer’s.
35. Rembrandt, Anatomy Lesson of Dr. Deijman.
Many of the views which have been advanced are highly speculative, and some no doubt will prove erroneous; but I have in every case given the reasons which have led me to one view rather than to another.… False facts are highly injurious to the progress of science, for they often endure long; but false views, if supported by some evidence, do little harm, for every one takes a salutary pleasure in proving their falseness.
Charles Darwin, The Descent of Man
Preface: Questions About the Brain to a Supposed Expert
I know full well that the reader has no great desire to know all this, but I have the desire to tell them of it.
Jean-Jacques Rousseau
Perhaps the two greatest scientific questions of this century are “How did the universe come into being?” and “How does the brain work?” Through a combination of my surroundings and chance, I became fascinated by the second question.
I grew up in a household where I overheard such enthralling conversations about every aspect of medicine that it became impossible to escape going into the profession. My father was a gynecologist who devoted his working life to many aspects of reproduction that were then highly controversial, like male infertility, artificial insemination, and the contraceptive pill. He received a stream of visits from friends whom I only later realized were pioneers in their fields. As a small child I got my first lessons in endocrinology from Dries Querido, who later set up Rotterdam’s medical faculty. When I noticed our family dog cock his leg against a tree as we took it for a walk, Professor Querido explained that his behavior was caused by the effect of sex hormones on the brain. Coen van Emde Boas, the first Dutch professor of sexology, used to drop by in the evenings with his wife for a drink. His stories were gripping, particularly for a small boy. I recall an anecdote he told about a patient with whom he was having trouble communicating. Finally the man came out with what had been bothering him: He had heard that Van Emde Boas was a homosexual! Van Emde Boas put an arm around his shoulders and said, “But my dear, surely you don’t believe that?” We laughed uproariously when he described the look on the patient’s face. It was a household in which there was no question you couldn’t ask, and during the weekends my father let me look at his medical books and peer through his microscope at plant cells and unicellular creatures fished out of local ditches.
When I was in secondary school, my father took me with him on a lecture tour of the country. I will never forget the hostile response he got from very religious members of the audience when he lectured on the contraceptive pill, which was going to be tested in the Netherlands for the first time. Despite the insults hurled at him, he went on arguing his case, remaining outwardly calm, while I sat sweating next to him, in an agony of embarrassment. In retrospect it was good training for the extremely heated reactions that my own research would later spark. An occasional visitor to our house at that time was Gregory Pincus, the developer of the contraceptive pill. I got my first sight of a laboratory when I was taken along with him on a visit to Organon, the pharmaceutical factory where the pill was produced.
With such a background it seemed to me self-evident that I would study medicine. At meals I would enthusiastically discuss medicine with my father so directly and in such detail that my mother would regularly beg us to stop, even though, having worked as an operating theater nurse and at the front during the war between Russia and Finland in 1939, she was hardly squeamish.
As my medical studies progressed, I was taken aback to discover that I was no longer expected merely to ask questions but also to provide answers. Suddenly everyone around me saw me as an expert on all kinds of health problems and expected free consultations. At one point I was so fed up with hearing about my aunt’s nagging pains that I silenced an entire family birthday party with a loud, “How interesting, Aunt Jopie! Take your clothes off, and let’s have a look at it!” It worked like a charm; she never bothered me again. The other relatives, though, proved harder to deter, and they continued to seek my advice.
During my studies I wanted to find out more about the experimental work that underpins medical knowledge. I also wanted to pay my own way through school, an idea to which my parents were very much opposed. There were two places in Amsterdam that would take you on as a part-time researcher once you got a basic medical degree after three years of study: the Department of Pharmacology and the Netherlands Institute for Brain Research. The first vacancy to come up just happened to be at the latter. So much for career planning. At the Institute for Brain Research I chose the logical area of focus, given my background: the new field of neuroendocrinology, involving research into hormone production by brain cells and the effect of hormones on the brain. During my interview with the institute’s director, Hans Ariëns Kappers, I mentioned that my main interest lay in neuroendocrinology, so the in-house expert, Hans Jongkind, was called in. He revealed my considerable ignorance on the subject with a series of probing questions. But to my surprise, Hans Kappers then said, “Well, we’ll give you a trial,” and I got the job.
For my PhD I carried out experiments to determine the functions of hormone-producing neurons. I did this research while continuing to study medicine, which kept me busy around the clock. It was with some difficulty that in 1970, while working as an intern in a surgical department, I obtained the afternoon off to defend my PhD thesis. After qualifying as a general physician in 1972, I decided to continue with brain research. In 1975 I became deputy director of the Nethe
rlands Institute for Brain Research (see chapter 15) and in 1978 its director. In 1979 I also took on the chair of neurobiology at the University of Amsterdam’s medical faculty. Despite holding these administrative posts for thirty years, hands-on research remained my main focus. After all, that was why I chose the profession. In my research group I’ve profited immensely from the knowledge of a host of talented and critical students, PhD students, postdocs, and staff members from over twenty countries, whom I still encounter in brain research centers and clinics all over the world; it’s a learning process that continues to this day. In turn, all of those academics owe much to the excellent technicians who have developed and perfected new research skills.
Meanwhile, I was getting more and more requests for information, including about issues outside of my own field. As a doctor, even if you’re engaged in research rather than general practice, people will come to you with pressing questions. There’s no aspect of life that brain disorders don’t touch, so my advice was solicited on the most serious issues. One Sunday morning, for instance, the son of an acquaintance knocked on my door with a few scans under his arm. He said, “I’ve just been told that I only have three months to live—how can that be?” When I looked at the scans, it seemed incredible that he’d even been able to visit me and ask this question: The front of his brain was one giant tumor, and indeed he did die shortly afterward. At such times all I can do is listen, explain the results of tests, and help desperate people to find their way through the medical jungle. The only accurate judges of my capacities were my children, who, when they were feverish and saw me appear at their bedside with a worried air and a stethoscope, would always insist that they wanted a “real” doctor.
When I set up the Netherlands Brain Bank in 1985 (see chapter 19) and became known for examining the brains of dead people, I was again surprised to find myself the focus of a great many questions on every subject relating to the final stage of life: euthanasia, assisted suicide, and the donation of brains and bodies to science; in short, everything connected to life and death (see chapter 19). My research became intertwined with personal and social issues relating to my field. I spoke with the courageous mothers of schizophrenic children who had committed suicide; they responded by setting up a national support network. At international conferences on Prader-Willi syndrome, I also discovered how often the relatives know more than the researchers do. At those conferences, the parents brought their morbidly obese children from every corner of the globe, taught researchers a great deal about the condition, and encouraged us greatly in our attempts to find out why sufferers eat themselves into an early grave. Interacting directly with researchers is an approach that more patient groups should emulate.