Man and Woman, Part Three: The Sex Life of the Brain

a growing number of scientists believe that maleness and femaleness are conditions we're plunged into--headfirst

Mrs. went is am ordinary, well-adjusted English housewife, married and with adopted children. Although she is legally a woman, she is, in fact, genetically male--all her cells contain both the female X and the male Y chromosome. But she suffers from a rare disorder called the testicular feminization syndrome, which involves an insensitivity to the main male hormone, testosterone. And, because of it, Mrs. Went was born with testes hidden in her abdomen while having all the external appearances of a girl. She was raised as a girl. She discovered her condition only at 23, when, anxious about her failure to menstruate or grow pubic hair during puberty, she consulted a gynecologist.

In Mrs. Went's case, gender identity--what sex she feels she is--has come unglued from her genetic sex. And there are other examples of this phenomenon. There are transsexuals who feel imprisoned in the sex of the body they were born with and who sometimes clamor for sex-change operations. There is a subgroup of homosexuals and transvestites who identify strongly with the sex opposite to their own--such as the New York transvestite who fathered and then, manipulated by hormones, breast-fed his own child. And then there are hermaphrodites. Hermaphrodites, true bisexuals, both male and female, born with one active ovary and one active testis and the ability, under certain circumstances, to impregnate themselves. Usually, however, they are raised as either boys or girls--in one gender identity or the other. And that is the gender identity they choose to keep, even when they have not been surgically altered in infancy to reflect it.

In the late Seventies, for example, a Mr. Blackwell, a shy 18-year-old Malawian who had been raised as a boy but who was, in fact, the 303rd true hermaphrodite known to medicine, entered Stellenbosch University Hospital in South Africa, where Willem van Niekerk had been conducting a study of Bantu hermaphrodites. Blackwell had both a penis and a small vaginal opening. But the main reason he sought medical help was that during puberty he had developed two large and finely shaped female breasts. Certain that he was a man, and wishing to continue his career as one, Blackwell asked doctors to stitch up his vagina and remove his breasts. And they did so.

Mrs. Went, Mr. Blackwell, transvestites, homosexuals and transsexuals such as Renée Richards, the tennis player--it was cases like those that confirmed the conventional wisdoms science delivered up to us in the Sixties and Seventies about sex and gender identity. Derived from Freud, they assumed that the human brain came into the world innocent of sex and was only later imprinted--through experience and education--with male and female patterns of behavior. That notion fit the confident liberalism of the times and it soon permeated the society. It encouraged ordinary citizens to bring up Jenny and Johnny in a democratic, unbiased way.

It encouraged surgeons, when they were faced with an infant with ambiguous sex organs, to plump surgically for one sex or the other and to leave the rest to hormone treatments and the long, slow schooling of childhood. And it encouraged psychiatrists to root around in the early experience of male and female homosexuals, just knowing that they would find there mixed messages, poor role models and a general confusion in the way they were raised.

This was the age of nurture over nature. First, said the scientists, a child can learn to be either male or female quite comfortably, whatever its genetic sex. But after a certain age, after it's learned to be one or the other, it cannot then change its gender assignment without a great deal of psychological trouble. Second, said the scientists, sex roles are not innate but learned. Gender is something dinned into you at your mother's knee, by your father's attitude and by all the assumptions about the sexes in the society into which you're born. Nature, they said, has little or nothing to do with it. Nurture is all.

Common sense, you would think. But then, in 1972, the descendants of Amaranta Ternera were discovered. And the controversy began. Amaranta Ternera--we have been asked to change her name and the (continued on page 212)Man and Woman(continued from page 145) names of her descendants--was born 130 years ago in the southwest corner of a Caribbean island. There was nothing wrong with Amaranta, as far as we know--she seems to have led a normal and ordinary life. But there was something wrong with the genes she left behind in her children. Seven generations later, Amaranta's genes have been located in 23 families in three separate villages. And in 38 individuals in those families, the strange inheritance that Amaranta passed down to them has been expressed. Those 38 were born, to all appearances, as girls. They grew up as girls. And they became boys at puberty.

Take the ten children of Gerineldo and Pilar Babilonia, for example. Four of them have been through this extraordinary transformation. The eldest, Prudencio, was born with an apparent vagina and a female body shape. He was christened Prudencia and, Pilar swears, was tied to his mother's apron strings and kept apart from the village boys to help with women's work. But then his voice began to deepen; around the age of 12, his "clitoris" grew into a penis and two hidden testicles descended into a scrotum formed from the lips of his "vagina." He became a male. "He changed clothes," says his father. "And he fell in love with a girl almost immediately."

Today, Prudencio is in his early 30s, a brawny, elaborately muscled man. He is sexaually potent and he lives with his wife in the United States. Like 17 of the 18 children studied by a group at Cornell University led by scientist Julianne Imperato-McGinley--all of whom, she says, were raised unambiguously as girls--he seems to have had few problems adjusting to both male gender and male roles.

It is that that makes Prudencio and the other Caribbean children important. And it is that that has caused, in the Eighties, side-taking and a general furor in the scientific community. Prudencio and the others are genetically male. But they have inherited from Amaranta not a general insensitivity to testosterone, like Mrs. Went's, but an inability to process it on to another hormone, dihydrotes-tosterone, which is responsible for shaping the male genitals in the male fetus. So they are born looking like girls. At puberty, though, their bodies are pervaded by a new rush of male hormones. Their male parts--which have been waiting in the wings, so to speak--finally establish themselves. And nature finishes the job it had earlier botched.

The children, though, do not have the psychological breakdown that the conventional wisdom of science predicts they should have. And that is crucial. For it means, depending on which side you're on in this scientific brouhaha, one of two things. Either the children were really raised as boys from the beginning, or at least with a great deal of confusion about what sex they were (which their parents and Imperato-McGinley deny), or they were born with a male brain already established in their female bodies, a male brain that simply came into its own when their bodies changed. By that argument, not only the body is sexed at birth but also the brain. And by that argument, nature, in gender behavior, is every bit as important as nurture. Learning may have little to do with it.

That is the scientific possibility of the Eighties, underwritten to an extent by the bizarre experience of the Caribbean children and suggested further by a whole range of experiments and studies being conducted in laboratories around the world. And that possibility strikes right at the heart of a number of attitudes we hold dear. It is no wonder, then, that feminists and homosexuals, as well as scientists from all fields, are beginning to join this fray. For if the claims of nature--as against those of nurture--are upheld, then it may be that we will have to give up the struggle to make Jenny and Johnny alike, in an attempt to do away with the sexual inequalities of the past; Jenny and Johnny may be born with intrinsically different abilities and skills, acquired through evolution. And it may be that we will have to accept the fact that those who become homosexual in adult life are not in some sense "male" by the environment in which they were brought up. Nor are they the product of a free choice. Rather, they were born homosexual, in the body of one sex but with the brain--to one degree or another--of the other sex. Günter Dörner, an East German professor whom we met at a recent conference in Cambridge, England, believes that to be true, especially in males. And he believes that society should now face the question of whether or not it wants to "cure" male homosexuality in the womb by giving fetuses at risk male hormones.

Nature versus nurture. Men versus women. Are sex and sexual behavior learned? Or are we prisoners of gender? From the accidents of nature, there is evidence on both sides. And that is what makes the debate often so angry. There are the cases of Mrs. Went and Mr. Blackwell, as we have seen--both of them content with the sex of their rearing. And there is the case of the American male identical twin whose penis was accidentally severed at seven months--the twin was surgically altered and is being successfully raised as his brother's sister. Those all demonstrate the dominant importance of learning in sexual behavior.

But other cases and reports, equally bizarre, support the thesis that masculinity and femininity are actually hard-wired into the brain before birth and are not simply learned by the child. There is the patient seen by Richard Green of the State University of New York who was born with ambiguous genitals and raised as a girl but insisted throughout childhood that she was a boy--she threw away her dolls and took up trucks; she formed male peer groups; and she was extremely tomboyish. There is the patient seen by Robert Stoller of the University of California who looked like a girl and was raised as a girl and, after a decade of demanding to be treated as a boy, was told at puberty that she was right--she had undescended testicles. There is still, too, the puzzling case of the Caribbean children. In the past five or six years, Imperato-McGinley, from her base at Cornell, has tracked down several other instances of the rare Caribbean syndrome. And she has found an odd corollary to their story. Of the children born outside the United States, all seem to have made the transition from female to male relatively comfortably--in a New Guinea tribe in which the sexes are segregated at birth and raised separately, two "girls" had to be suddenly rushed through puberty rites and initiated as men.

But the eight children she found from this country were recognized as odd soon after birth, and all traces of masculinity, including a relatively enlarged clitoris, were surgically removed. Those children were made into girls. They are now in their late teens and consider themselves female, but five of them seem to have psychological problems, says Imperato-McGinley. It is not clear that they can make it as women.

If they can't, the reason, quite simply, may be that their brain is the wrong sex for their body. Primed to be male, it finds itself in a female environment--encouraged to female behaviors and exposed to female hormones. And it cannot cope. This is the bottom line of the science of the Eighties: the brain. And this is the question being urgently asked by more and more scientists from different disciplines: Are the brains of males and females as different as their bodies? It is a vital question for scientists, because the differences between males and females provide a way into the question of how the brain orchestrates different motivations and behaviors. But it is a vital question for us, too. For in the answer may lie an understanding of who we are as men and women--our place in nature, our gifts and the evolved purpose behind our relationships.

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Your brain is not an isolated organ; it is an integral part of what appear to be the outlands of your body. Your retinas, for example, which you are using to read this, are one of your brain's ways of gathering information about its environment. The sensory nerves in your fingers, as you continue to hold these pages open, are your brain's way of learning what the fingers are touching. And the nerves in your muscles, as you shift your arms and flex your legs, are no more than your brain's agents for making you move about. At one end of the scale of your life, as you sit or lie or loll here, is the world of the senses--information delivered to your brain by light (sight), chemicals (taste and smell) and mechanical forces and pressures (hearing and touch). At the other end are your brain's responses to that world and its attempts to influence it: your skimming of a paragraph or reaching for a cup. And between the two stand thought, memory, pleasure, boredom, foresight, personality and gender identity--everything that makes men and women human: your brain. It is a forest of 100 billion nerve cells in the bone case of your skull, whose branches, if laid end to end, would stretch to the moon and back. It is two pinkish-gray handfuls of gelatinlike tissue, whorled like a walnut, turned in upon itself, hungry for oxygen and chemical energy and driven by enough electricity to light a small light bulb. It is also who you are.

"You" is always a shorthand for "your brain"; "I," for "my brain." When you feel pain, it is your brain that feels it; when you use a drug to control it, it is your brain that you are treating. When you take a drink or a smoke or a upper, it is your brain that is seeking to alter and manipulate its own chemistry. And when you are sexually aroused, it is your brain that organizes the behavior that will lead to its own fulfillment. The roots of every action and every skill are in the brain. The brain is the conductor of the body's orchestra of hormones--including the sex hormones. It is imprinted and influenced itself by those hormones. It is the organ of human personality. But it is also a gland--a thinking gland, a dreaming gland, a sex gland.

"Is it differently sexed in men and women? If so, at what stage of development? And if so, by what processes? These are the questions." Diane McGuinness is a research psychologist who has been investigating human sex differences for the past ten years. A stylish and voluble woman who holds positions at both stanford and the University of California at Santa Cruz, she is one of the few scientists to work exclusively in the field of male-versus-female behavior, doggedly persevering in the face of criticism from other scientists anxious about the implications of her work. "The problem is that these questions are extremely hard to answer," she says. "Yes, there obviously is a part of the brain--the hypothalamus--that is differently sexed. It's the brain's controller of the flow of hormones. And it's responsible for the way sex-and-reproductive behavior is organized--the menstrual cycle in women and the quite different picture we see in men. The hypothalamus is almost certainly differently stamped before birth by sex hormones. It's like a photographic plate that is exposed before birth and then developed by a fresh rush of hormones at puberty.

"But how about the rest of the brain? We can't, after all, just cut into a normal male or female brain, in good working order, and ask it what's going on. And we can't learn much, either, from a brain when it's dead and pickled or frozen and cut into slices for the microscope. It's no use, in other words, approaching the human brain head on. It can't tell us what we want to know. It's dumb." McGuinness spreads her hands and reaches for a cigarette. "So we have to get smart. We have to come up with new ways of looking at it from the outside and of measuring what it does from the outside. And then we have to fit together what we've found out--our piece of the puzzle--into a general pattern or design that makes sense. This is what we try to do. We try to build up a picture of what is going on in male and female brains from a series of different takes."

The View from Outside. Take One: Palo Alto, California. One avenue into the complexities of the individual human brain is through the way it responds to the world: its behavior. Another is through the skills and abilities it shows when confronted with controlled tasks in a controlled environment. Those are the avenues taken by behavioral and cognitive psychologists into the brain's mysteries. Over the past decade, McGuinness and colleagues at Stanford, Eleanor Maccoby and Carol Jacklin, have separately observed and tested thousands of infants, preschoolers, high school and university students. And out of those studies and others has emerged a picture that indicates quite wide statistical differences between human males and females.

"Some of those differences appear extremely early in life," says McGuinness, "and others are more obvious after puberty. But the fascinating thing is that they seem to be independent of culture--as true in Ghana, Scotland and New Zealand, for example, as they are in America. First, there are differences in the senses. Women are more sensitive to touch, tastes and odors--especially, it seems, at mid-cycle. They also have better fine-motor coordination and finger dexterity. Second, there are differences in the way information is gathered and problems solved. Men are more rule bound and they seem to be less sensitive to situational variables: more singleminded, more narrowly focused and more persevering. Women, by contrast, are very sensitive to context. They're less hidebound by the demands of a particular task. They're good at picking up peripheral information. And they process their information faster.

"Put in general terms, women are communicators and men are takers of action. Because that's the implication of the most important difference between them, the one that's most widely accepted. Males are better at maps, mazes and math; at rotating objects in their minds and locating three-dimensional objects in two-dimensional representations. They're better at perceiving and manipulating objects in space. They have a better sense of direction.

"Females, on the other hand, excel in areas males are weak in, especially in areas where language is involved. They're not as good at anything that requires object manipulation and visual sharpness--they're less sensitive to light, for one thing. But they're much better at almost all the skills that involve words: fluency, verbal reasoning, written prose and reading--males outnumber females three to one in remedial-reading classes. Females' verbal memory is also better. And they can sing in tune six times more often than males can.

"The question, of course, is: Are these things learned--encouraged by parents and teachers--or are they innate? How early do they show up in the brain?

"And the answer is: Very early. We see certain tendencies almost from the beginning. Male infants respond to what is visually catching in their environment--lights, patterns. three-dimensional objects. And when they're a little older, they take on their physical environment more than females do. They're more curious about it. They play with the objects in it as often as with toys. They draw objects rather than people. And they throw themselves around more--they develop better gross-motor control.

"This is not what we find in female infants. Girls respond preferentially to the people in their environment. What's visually catching for them is faces rather than objects. They're also much more sensitive to sound. They vocalize more and are more comforted by speech than boys are. And they respond more to the social sounds around them, to tones of voice and to music. That is crucial. I think. In the first place, sensitivity to sound is something that persists throughout life in women--sounds are likely to seem twice as loud to them as to men, something men would do well to remember sometimes. And, in the second place, it is almost certainly an important contributor to females' verbal abilities. Sounds and people, remember--as against objects in space. Communication versus action and manipulation. It's there in the brain from the beginning. The language ability of females is not affected by a traumatic early environment, as it is in males. And it is not differentially encouraged in them by their parents."

So just as the capacity for language is hard-wired into human brains before birth, is that true of a special skill in it?

"Yes," says McGuinness. "What comes easily to each sex is likely to be biologically programed: stamped, waiting to be developed."

Take Two: Chicago, Illinois. "Aaaall right." Jerre Levy is sitting in her cluttered office at the University of Chicago, one leg curled under her. She swoops periodically into a cup of coffee. "So you have these different abilities. And you have the not uninteresting fact that males and females also characteristically suffer from different disabilities: females from depression and hysteria, but also maybe from math disability; and males from hyperactivity, autism, dyslexia and stuttering--language disabilities.

"There are two things, though, you've got to remember about these differences. First, they're statistical differences-- averages. And they're extremely minor compared with differences between people of the same sex--of all the variations we observe among people, 80 to 95 percent or more of them are within men and within women. They're by no means cut and dried in every male and female. Second, the average sex differences that we do observe should never be allowed to have any effect on social policy, such as encouraging Jenny to give up math and Johnny to give up languages. If bio-logical differences, after all, were to be made the basic of social policy, then the first thing we should do is lock up all the men, since they're the ones who commit almost all the crime. They're more aggressive. And they're the ones at risk of being psychopaths."

Levy is an incisive and highly original biopsychologist, a dark-haired woman in her early 40s whose dazzling talk is replete with the corkscrew vowels and sudden emphases of her native Alabama. And her way into the differences between men and women is through the separate responsibilities of the brain's two hemispheres. She is one of the scientists who worked out in split-brain patients the way in which the human brain is lateral-ized--the analytic left hemisphere specializing, by and large, in language, and the holistic right hemisphere specializing in visual tasks and the perception of spatial relationships. And since then, she--with others--has devised a cluster of tests designed to investigate this lat-eralization in normal people. In doing so. she has helped open up a new avenue of investigation into sex differences: not only in how abilities differ but in how those abilities are organized in the brain.

"All right, what we're talking about is the selective activation of one hemisphere or the other," Levy says, "which hemisphere responds to what sort of stimulus in males and females. Now, the left hemisphere controls and receives messages from the right side of the body, and vice versa. But it is also activated by objects in the right visual field and by sounds perceived by the right ear. There is a crossover.

"This means that we can broadcast directly to one hemisphere or the other. We Can use a technique developed by Doreen Kimura of the University of Western Ontario, for example. We can present the two ears simultaneously with different sounds, for example--sometimes verbal and sometimes nonverbal--and see which of the two sounds is reported by the hearer: which hemisphere, therefore, specializes in processing and interpreting that sort of sound. We can also, for just a few hun-dredths of a second, flash in front of a subject pictures, words, digits, letters and dots and lines oriented to a central point either in the left visual field or in the right visual field or in both. And, again, we can see which hemisphere is faster and better at recognizing and processing which sort of information--verbal, nonverbal, spatial and so on. That will depend on the handedness of the subject. Almost all right-handers organize language on the left side and certain types of visual-spatial skills on the right side of the brain--left-handers are much more confusing. And it may depend on the sex of the subject."

She pauses for a moment to collect her thoughts. "Look," she says, "there are only little pieces of evidence. This is a very young field and our techniques are crude; we're trying to become more sophisticated as we go along. But what evidence there is indicates that the female brain may be less lateralized and less tightly organized than the male brain. In male right-handers. for example, language seems to be rather rigorously segregated to the left hemisphere, while their visual-spatial skills are as rigorously segregated to the right. That does not seem to be true in right-handed females. Their hemispheres seem to be less functionally distinct from each other and more diffusely organized.

"OK. What might this mean? It might mean that there are two sorts of differences in the way male and female brains are organized and function: interhemi-spheric differences--differences in the way the hemispheres communicate--and intrahemispheric differences--differences in the amount of brain space on each side given over to particular abilities. The hemispheres of male brains. you see, seem to be specialists--they speak different languages, verbal and visual-spatial. And it may be that they can communicate with each other only in a formal way. after encoding into abstract representations. The hemispheres of female brains, on the other hand. may not be such specialists. And they may be able to communicate in a much less formal and less structured way. If that is so, then females may be much better than males At integrating verbal and nonverbal information--at reading the emotional content of tones of voice and intensities of expression, for example; at interpreting social cues such as posture and gesture: and at quickly fitting all sorts of different information in different modes into a complete picture. This may be at the root of what we call female intuition.

"This is entirely speculative, of course. But it might be borne out by differences within each hemisphere. In the male's left hemisphere, for example. language may be deployed in brain space rather differently from the pattern in the female's. Possibly the female evolved language as a tool for communication, while the male evolved it as a tool for a more specialized task--analytical reasoning. Similarly, it may be that in the right hemisphere males have given over a great deal more neural space to their visual-spatial skills. while females have not. And that may mean that females have been able to deploy in their right hemisphere other types of nonverbal skills--such as emotional sensitivity-- that the male right hemisphere cannot accommodate so well.

"If that is true. then males may be at a double disadvantage in their emotional life. They may be emotionally less sophisticated. And because of the difficulty they may have in communicating between their two hemispheres. they may have restricted verbal access to their emotional world."

"Female intuition," says one of us as we walk outside into a bustle of students.

"Men's difficulty with emotions," says the other. In the brain.

Take Three: London, Ontario. North to Canada. To Doreen Kimura and her former student Jeannette McGlone at Western Ontario's University Hospital--and to another line of evidence that underwrites much of what Levy suggests. Kimura and McGlone have been working on the different effects of brain damage--tumors and strokes--in right-handed men and women. And what they've found does, indeed, show that women are much less at risk than men from that sort of injury. The reason may be because the male brain is so laterally specialized--damage to one hemisphere or the other virtually always produces a loss in language (left) or spatial skills (right), says McGlone: in the female brain, that is not so much the case. Or it may be because language is more focally organized--and therefore better protected--in the female's left hemisphere, as Kimura is now finding. The word is not yet in on what precisely are the differences between male and female organization of those particular abilities. But that there are differences within and perhaps between the hemispheres of men and women is now clear. The question is. why.

Take Four: Seattle, Washington. In Seattle, neurosurgeon George Oje-mann-working with another former student of Kimura's, Katie Mateer--has been using electrical stimulation to locate language functions in the exposed brains of epileptic patients needing surgery. In two distinct, well-defined areas of the left hemisphere, they have found a quite different distribution in males and females. The brain map for language is different within the hemi-sphere--confirming Levy's prediction and Kimura's latest work. Why?

Take Five: Philadelphia, Pennsylvania. In Philadelphia, a young Israeli scientist, Ruben Gur, has Israeli scientist, Ruben Gur, has used a radioactive gas to show that male and female brains are both differently constituted and differentially supplied with blood when at work on certain tasks. Why?

Take Six: London, Ontario. At lunch with Kimura, we press the question. "Well." she says. "we have to look at the separate evolutionary pressures on men and women," Kimura is a small. trim woman in her 40s. a scientist with a wide international reputation. She is secure enough to speculate. "First, let us suppose that language was a relatively recently acquired skill. And let's assume that when the male and female of a species differ in the development of a skill, there will be a different amount of brain space given up to that skill--this is true, we know, in birds. Now, we also know that for 99 percent of our history, we've been hunter-gatherers. And in a hunter-gatherer society, there would be strong selective pressure on the males to be highly specialized. To hunt successfully--which meant survival, genetic and otherwise--they would need eye acuity, goal-directedness, good gross-motor control and the ability to calculate distance, direction and the essentials of a situation: exactly the sort of visual and spatial skills psychologists find in human males today. To achieve those skills, though, they would need to give up to them a good deal of brain capacity--neural space. And they would not have that space available for the abilities it became necessary for them to acquire later. Or--put another way--those later abilities would have to subserve the spatial and motor abilities they already had.

"Females, meanwhile--let us imagine--were subject to different evolutionary pressures and were being selected for different qualities from the males." She laughs, aware of the controversy to which her and her students' work has contributed. "And those qualities--maternal, social and cultural ones--required different motor skills and a different brain organization. When language and its uses were acquired, then, they fitted rather differently into the architecture of the female brain. One suggestion is that they were free to be more flexibly expressed in both hemispheres, without having to be confined to the left, as in males. But more accurate, I think, is that they slotted into motor systems that were already somewhat differently developed from the male pattern. The result, again, might be what we see: a different organization of language in the left hemisphere and the different constellation of abilities with language that psychologists find in women today. All this, you see, would be underwritten by evolution, directed by sexual selection and laid down in the male and female brain. It would still be there."

What does this have to do with Mrs. Went? With Prudencio Babilonia and the other Caribbean children? Well, evolution can work only through the inheritance of genes. And the only genetic difference between males and females, as we have said, is that out of 46 pairs of chromosomes, there is one that is different--females have two X chromosomes and males an X and a Y. Now, both Mrs. Went and the Caribbean children were XY--they were genetic males. So why were they born looking like females? Because something had gone wrong with their processing of the main male hormone for which the Y gene is ultimately responsible. Their Y gene, in other words, did not--and does not--guarantee maleness. Only the action of the sex hormones can do that. Sex hormones are responsible for the shaping of the genitals, for the different priming of the hypothalamus and, ultimately, for a large number of differences between males and females--in bone formation, musculature, kidney function and pelvis size. They are also responsible, say scientists, for the shaping of the male and the female brain.

That is what we'll be exploring next month: everything that science is now finding out about the separate inheritance of our sex hormones. We'll be taking you back into the womb from which you came. And we'll be introducing you to new work in endocrinology and neurobiology that confirms or suggests the following:

The most controversial of those points--those about homosexuality, hormones and the brain--involves the work of Günter Dörner, the man we met at the conference in Cambridge. We'll be meeting him again next month.