Homosexuality and Biology

An introduction to a muddled and sometimes contentious world of scientific research—one whose findings, now as tentative as they are suggestive, may someday shed light on the sexual orientation of everyone

The issue of homosexuality has arrived at the forefront of America's political consciousness. The nation is embroiled in debate over the acceptance of openly gay soldiers in the U.S. military. It confronts a growing number of cases in the courts over the legal rights of gay people with respect to marriage, adoption, insurance, and inheritance. It has seen referenda opposing gay rights reach the ballot in two states and become enacted in one of them—Colorado, where local ordinances banning discrimination against homosexuals were repealed. The issue of homosexuality has always been volatile, and it is sure to continue to inflame political passions.

It is timely and appropriate that at this juncture a scientific discipline, biology, has begun to ask the fundamental question What is homosexuality? And it has begun to provide glimmers of answers that may in turn not only enhance our self-knowledge as human beings but also have some influence, however indirect, on our politics.

What makes the science in this case so problematic, quite apart from the usual technical difficulties inherent in biological research—particularly neurobiological research, which accounts for much of the present investigation—is the ineffable nature of our psychosexual selves.

This encompasses a vast universe of stimulation and response, of aesthetic and erotic sensibilities. There are those who see an element of hubris in the quest to explain such things in biological terms. Others see not so much hubris as hype: certain well-publicized findings, they fear, could turn out to be milestones on the road to an intellectual dead end.

It is undeniably true that neurobiological research is often pursued in a context of great ignorance. The brain remains an organ of mystery even in general, not to mention with regard to specific functions. "We don't know" may be the most frequently used words in neurobiology, and they seem to be used with special frequency when the subject of sexual orientation comes up. Once, I mentioned to a researcher how often I heard these words on the lips of her colleagues, and she replied, "Good—then they're saying the right thing." In this context, and also considering that the subject matter is politically charged, professional rivalries are inevitable and occasionally bitter. Some of those involved in the research are motivated not only by scientific but also by personal concerns. Many of the scientists who have been studying homosexuality are gay, as am I.

Homosexuality's invitation to biology has been standing for years. Homosexuals have long maintained that sexual orientation, far from being a personal choice or lifestyle (as it is often called), is something neither chosen nor changeable; heterosexuals who have made their peace with homosexuals have often done so by accepting that premise. The very term "sexual orientation," which in the 1980s replaced "sexual preference," asserts the deeply rooted nature of sexual desire and love. It implies biology.

Researchers can look back on two histories: a century-long, highly problematic psychological investigation of homosexuality, and a short but extremely complex history of biological research that started out as an examination of ovulation in rats. Three distinct but interrelated biological fields are involved in the recent work on sexual orientation: neuroanatomy, psychoendocrinology, and genetics.

The Background

Biologists embarked upon research into homosexuality in response to an intellectual vacuum created by the failure of other sciences to solve the riddle of sexual orientation. "Other sciences" mostly means psychiatry. As Michael Bailey and Richard Pillard, the authors of one of the most important genetic inquiries into homosexuality, have observed, decades of psychiatric research into possible environmental causes of homosexuality—that is to say, social and cultural causes—show "small effect size and are causally ambiguous."
As a distinct concept, homosexuality is relatively recent. David Halperin points out in One Hundred Years of Homosexuality that the term itself first appeared in German (Homosexualität) in a pamphlet published in Leipzig in 1869; it entered the English language two decades later. That some human beings engage in sexual activity with others of the same sex has, of course, been noted since antiquity. Historically, however, the focus was on the acts themselves rather than on the actors. The historian John Boswell, of Yale, has noted that during the Middle Ages "same-sex sex" was regarded as a sin, but those who committed that sin were not defined as constituting a type of people different from others. Between the sixteenth and the eighteenth century same-sex sex became a crime as well as a sin, but again, those who committed such crimes were not categorized as a class of human being. This changed in the nineteenth century, when modern medicine and particularly the science of psychiatry came to view homosexuality as a form of mental illness. By the 1940s homosexuality was discussed as an aspect of psychopathic, paranoid, and schizoid personality disorders.

Having defined homosexuality as a pathology, psychiatrists and other doctors made bold to "treat" it. James Harrison, a psychologist who produced the 1992 documentary film Changing Our Minds, notes that the medical profession viewed homosexuality with such abhorrence that virtually any proposed treatment seemed defensible. Lesbians were forced to submit to hysterectomies and estrogen injections, although it became clear that neither of these had any effect on their sexual orientation. Gay men were subjected to similar abuses. Changing Our Minds incorporates a film clip from the late 1940s, now slightly muddy, of a young gay man undergoing a transorbital lobotomy. We see a small device like an ice pick inserted through the eye socket, above the eyeball and into the brain. The pick is moved back and forth, reducing the prefrontal lobe to a hemorrhaging pulp. Harrison's documentary also includes a grainy black-and-white clip from a 1950s educational film produced by the U.S. Navy. A gay man lies in a hospital bed. Doctors strap him down and attach electrodes to his head. "We're going to help you get better," says a male voice in the background. When the power is turned on, the body of the gay man jerks violently, and he begins to scream. Doctors also tried castration and various kinds of aversion therapy. None of these could be shown to change the sexual orientation of the people involved.

Among those who looked into the matter was the sex researcher Alfred Kinsey, whose 1948 report Sexual Behavior in the Human Male showed homosexuality to be surprisingly common across lines of family, class, and educational and geographic background. In his book Being Homosexual, the psychoanalyst Richard Isay writes,

Kinsey and his co-workers for many years attempted to find patients who had been converted from homosexuality to heterosexuality during therapy, and were surprised that they could not find one whose sexual orientation had been changed. When they interviewed persons who claimed they had been homosexuals but were now functioning heterosexually, they found that all these men were simply suppressing homosexual behavior. . . and that they used homosexual fantasies to maintain potency when they attempted intercourse. One man claimed that, although he had once been actively homosexual, he had now "cut out all of that and don't even think of men—except when I masturbate."
Psychiatry not only consistently failed to show that homosexuality was a preference, a malleable thing, susceptible to reversal; it also consistently failed to show that homosexuality was a pathology. In 1956, in Chicago, a young psychologist named Evelyn Hooker presented a study to a meeting of the American Psychological Association. Hooker had during her training been routinely instructed in the theory of homosexuality as a pathology. A group of young gay men with whom she had become friendly seemed, however, to be quite healthy and well adjusted. One of them, a former student of hers, sat her down one day and, as she recalls in Changing Our Minds, said, "Now, Evelyn, it is your scientific duty to study men like me." She demurred. It was only when a fellow scientist remarked to her, "He's right—we know nothing about them," that Hooker sought and received a study grant from the National Institute of Mental Health. She chose a group of thirty gay men as the objects of her research and thirty straight men as controls; none of the sixty had ever sought or undergone psychiatric treatment. "It was the first time [homosexuals] had been studied outside a medical setting or prison," she says. "I was prepared, if I was so convinced, to say that these men were not as well adjusted as they seemed on the surface."

Hooker administered psychological tests to her sixty subjects, including the Rorschach ink-blot test, producing sixty psychological profiles. She removed all identifying marks, including those indicating sexual orientation, and, to eliminate her own biases, gave them for interpretation to three eminent psychologists. One of these was Bruno Klopfer, who believed that he would be able to distinguish homosexuals from heterosexuals by means of the Rorschach test. As it turned out, none of the three could tell the homosexuals and heterosexuals apart. In side-by-side comparisons of matched profiles, the heterosexuals and homosexuals were indistinguishable, demonstrating an equal distribution of pathology and mental health. Reviewing Hooker's results from a test in which the subject creates pictures with cutout figures, one of the interpreters, a psychologist named Edwin Shneidman, stumbled onto a particular subject's orientation only when he came across a cutout scene depicting two men in a bedroom. Shneidman remembers, "I said to Evelyn, 'Gee, I wish I could say that I see it all now, that this is the profile of a person with a homosexual orientation, but I can't see it at all.'"

Hooker's research throughout her long career was driven by the belief that for psychiatry to be minimally scientific, pathology must be defined in a way that is objective and empirically observable. Her study was the first of many showing that homosexuality could not be so defined as pathology. In 1973 the American Psychiatric Association removed homosexuality from its official Diagnostic and Statistical Manual, signifying the end of homosexuality's official status as a disease. Today's psychiatrists and psychologists, with very few exceptions, do not try to change sexual orientation, and those aspiring to work in the fields of psychiatry and psychology are now trained not to regard homosexuality as a disease.

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