Gay people are often asked by the curious: When did you first realize you were gay?” In my case, I remember undressing my Superman doll--and being terribly disappointed at the result--as well as being motivated to befriend the more attractive boys in third grade. But hormonally speaking, it wasn’t until I was about fourteen that I first looked in the mirror and thought to myself, ah, that’s what I am all right, it all makes perfect sense now.

It wasn’t much of a mystery. After all, lust isn’t exactly a subtle thing. Back then I derived as much pleasure from making out with my “girlfriend” as I might have from scraping the plaque from my dog’s teeth. In contrast, barely touching legs with a boy I had a crush on sparked an electric, ineffable ecstasy. In the locker room after high school gym class, I forced myself to picture naked girls in my head (particularly my girlfriend) as a sort of cognitive cold shower, a pre-emptive strike against an otherwise embarrassing physical response. I could go on but you get the idea: whether or not we like, hide or accept what we are, our true identities--gay, straight, bisexual--consciously dawn on each of us at some point in adolescence. We all have a natural “orientation” towards sexual contact with others, and for the most part we’re just hopeless pawns, impotent onlookers, to our body’s desires.

At least, that’s what most people tend to think. But actually, some scientists believe that there may be a fourth sexual orientation in our species, one characterized by the absence of desire and no sexual interest in males or females, only a complete and lifelong lacuna of sexual attraction toward any human being (or non-human being). Such people are regarded as asexuals. Unlike bisexuals, who are attracted to both males and females, asexuals are equally indifferent to and uninterested in having sex with either gender. So imagine being a teenager waiting for your sexual identity to express itself, waiting patiently for some intoxicating bolus of lasciviousness to render you as dumbly carnal as your peers, and it just doesn’t happen. These individuals aren’t simply celibate, which is a lifestyle choice. Rather, sex to them is just so ... boring.

In one recent interview study published in a 2007 issue of the Archives of Sexual Behavior, a group of self-described asexuals was asked how they came to be aware they were different. One woman responded:

I would say I’ve never had a dream or a fantasy, a sexual fantasy, for example, about being with another woman. So I can pretty much say that I have no lesbian sort of tendencies whatsoever. You would think that by my age I would have some fantasy or dream or something, wouldn’t you? ... But I’ve never had a dream or a sexual fantasy about having sex with a man, either. That I can ever, ever remember.

In another interview study, this one by University of Michigan researcher Kristin Scherrer, an 18-year-old woman put it this way:

I just don’t feel sexual attraction to people. I love the human form and can regard individuals as works of art and find people aesthetically pleasing, but I don’t ever want to come into sexual contact with even the most beautiful of people.

According to Brock University psychologist Anthony Bogaert, there may be more genuine asexuals out there than we realize. In 2004 Bogaert analyzed survey data from more than 18,000 British residents and found that the number of people (185, or about 1 percent) in this population who described themselves as “never having a sexual attraction to anymore” was just slightly lower than those who identified as being attracted to the same sex (3 percent). Since this discovery, a handful of academic researchers have been trying to determine whether asexuality is a true biological phenomenon or, alternatively, a slippery social label that for various reasons some people may prefer to adopt and embrace.

Sexual desire may wax and wane over the life course or--as many people on antidepressants have experienced--become virtually nonexistent due to medications or disease. There are also chromosomal abnormalities, such as Turner’s syndrome, often associated with an absence of sexual desire. Traumatic events in childhood, such as sexual abuse, can also factor into an aversion to sex. But if it exists as a fourth orientation, true asexuality would be due neither to genetic anomaly or environmental assault; although little is known about its etiology (Bogaert believes it may be traced to prenatal alterations of the hypothalamus), by all appearances most asexual people are normal, healthy, hormonally balanced and sexually mature adults who, for still uncertain reasons, have always found sex to be one big, bland yawn. Asexuality would therefore be like other sexual orientations in the sense that it is not “acquired” or “situational,” but rather an essential part of one’s biological makeup. Just like a straight man or a lesbian can’t wake up one day and decide to become attracted to men, neither could a person--in principle, anyway--“become” asexual. Sexual dysfunctions such as Hypoactive Sexual Desire Disorder (HSDD) can also be ruled out if a “preference” towards a gender does not awaken in response to clinical intervention such as hormonal treatment. As Bogaert notes, even those with object fetishes or paraphilias usually display a gender-based attraction, such as men who have a thing for women’s shoes or necrophiliacs who have sex with dead women’s (but not men’s) bodies.

But the story of asexuality is very complicated. For example, as discussion on the AVEN (Asexuality and Visibility Education Network) website forums demonstrate, there is tremendous variation in the sexual inclinations of those who consider themselves to be asexual. Some masturbate, some don’t. Some are interested in nonsexual, romantic relationships (including cuddling and kissing but no genital contact), while others aren’t. Some consider themselves to be “hetero-asexual” (having a nonsexual aesthetic or romantic preference for those of the opposite sex), while others see themselves as “homo-” or “bi-asexuals.” There’s even a matchmaking website for sexless love called asexualpals.com. Yet many asexuals are also perfectly willing to have sex if it satisfies their sexual partners; it’s not awkward or painful for them but rather, like making toast or emptying the trash, they just don’t personally derive pleasure from the act. As researchers Nicole Prause and Cynthia Graham found in their interviews with self-identified asexuals, “they were not particularly sexually fearful ... they had a lower excitatory drive.” Others insist on being in completely sexless relationships, possibly with other asexuals. Thus, while many asexuals are virgins, others are ironically even more experienced than your traditionally sexual friends. Some want children through artificial means such as in vitro fertilization; others are willing to have them the old-fashioned way or don’t want children at all.

Thus, on the one hand there seems to be a sociological issue of people of a marginalized sexual identity gathering steam and beginning to form an identifiable community. (And in the process attracting significant media attention, including coverage on the Montel Williams Show, The View and an excellent feature story in New Scientist a few years ago.) On the other hand, there remains--to me--the more intriguing biological issue of asexual essentialism; that is to say, is it really possible to develop “normally” without ever experiencing sexual desire, even a niggling little blip on the arousability radar, toward any other human being on the face of the earth? I have little doubt that there are self-identified asexuals who would fail to meet this essentialist criterion, but if even a sliver of the asexual community has truly never experienced arousal, then this would pose fascinating questions for our understanding of human sexuality and evolutionary processes.

I still have a lot of questions. Scientists have just scratched the surface in studying human asexuality. You can count the number of studies on the subject on one hand. Does asexuality, like homosexuality, have heritable components? Certainly it’s plausible. After all, historically, female asexuals would have probably had offspring with their male sexual partners, thus ensuring continuity of the genetic bases of asexuality. Although Bogaert’s original findings suggested that asexuality was somewhat more common among women, more recent research by Prause and Graham found no such gender difference in their college-aged sample of self-reported asexuals. If some asexuals masturbate in the absence of sexual fantasy or porn, then what exactly is it that’s getting them physically aroused? (And how does one achieve orgasm--as some asexuals apparently do--without experiencing pleasure?) Also, if you’re on board theoretically with evolutionary psychology, almost all of human cognition and social behavior somehow boils down to sexual competition. So what would the evolutionary psychologist make of asexuality? If sex is nature’s feel-good ruse to get our genes out there, is there actually a natural category of human beings that is immune to evolution’s greatest gag?

I must say, the only good way to solve the riddle is also a bit unsavory. But unless psychological scientists ever gather a group of willing, self-identified asexuals and, systematically and under controlled conditions, expose them to an array of erotic stimuli while measuring their physical arousal (penile erection or vaginal lubrication), the truth of the matter will lie forever hidden away in the asexual's pants.

In this column presented by Scientific American Mind magazine, research psychologist Jesse Bering of Queen's University Belfast ponders some of the more obscure aspects of everyday human behavior. Ever wonder why yawning is contagious, why we point with our index fingers instead of our thumbs or whether being breastfed as an infant influences your sexual preferences as an adult? Get a closer look at the latest data as “Bering in Mind” tackles these and other quirky questions about human nature. Sign up for the RSS feed or friend Dr. Bering on Facebook and never miss an installment again. For articles published prior to September 29, 2009, click here: older Bering in Mind columns.

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