mercoledì 17 aprile 2013

Face gay-detector.


There's Something Queer about That Face

Without being aware of it, most people can accurately identify gay men by face alone

The January 2008 study investigated people's ability to identify homosexual men from pictures of their faces alone. In an initial experiment, researchers Nicholas Ruleand Nalini Ambady from Tufts University perused online dating sites and carefully selected 45 straight male faces and 45 gay male faces. All of these photos were matched for orientation (only faces shown looking forward were used) and facial alterations (none of the images contained jewelry, glasses or facial hair). To control for context, the faces were also cut and pasted onto a white background for the study. These 90 faces were then shown to 90 participants in random order, who were asked simply to judge the target's "probable sexual orientation" (gay or straight) by pressing a button. Surprisingly, all participants (both men and women) scored above chance on this gaydar task, correctly identifying the gay faces. Even more surprisingly, accuracy rate was just as good when the images were exposed at a rapid rate of only 50 milliseconds, which offered participants no opportunity to consciously process the photo.

A parsimonious explanation for these findings would be that the countenance of these photos—an online dating site—means that they're likely stereotypical in some way. In other words, perhaps it's not the target's face per se that signals his sexual orientation, but the way he expresses himself facially when trying to attract a member of the same or the opposite gender. Or maybe hairstyles are suggestive of sexual orientation. Wary of these possible criticisms, Rule and Ambady conducted a second experiment that controlled for such extraneous variables as self-presentation and hairstyle.

In this second study, the authors used images from the social networking site Facebook rather than online dating Web sites. This way, the targets hadn't so obviously selected photos of themselves meant to attract prospective sexual partners. In fact, the authors had a rather elaborate selection procedure for choosing the target photos in this follow-up study. They first searched for men who'd indicated in their Facebook profile an interest in other men. Then, they did a second search to find other Facebook users who had posted photos of these gay men in their own profile. They followed the identical criteria for straight targets. "Thus," the authors wrote, "by using photos of gay and straight individuals that they themselves did not post, we were able to remove the influence of self-presentation and much of the potential selection bias that may be present in photos from personal advertisements."

Again, the authors superimposed these male faces (this time 80 gay and 80 straight) onto a white background. They then photoshopped off the participants' hairstyles, this time truly leaving only the faces as a source of information about sexual orientation. And even with these more stringent controls, the participants were able to identify the gay faces at levels greater than chance—again even on those trials where the faces were flickered on the screen for a mere 50 milliseconds.

Furthermore, in an even more rigorously controlled series of experiments published in the Journal of Personality and Social Psychology, Rule and his colleagues replicated their discovery that people are able to accurately guess male sexual orientation. This time, the researchers demonstrated that perceivers were able to do this even when they were shown only individual features of the target's face. For example, when shown only the eye region ("without brows and cropped to the outer canthi so that not even "crow's-feet" were visible"), perceivers were amazingly still able to accurately identify a man as being gay. The same happened when shown the mouth region alone. Curiously, most of the participants underestimated their ability to identify gay faces from these features alone. That is to say, people seem to have honed and calibrated their gaydar without knowing they've done so.

Frankly, these findings are a little puzzling to me. Rule and his co-authors mention a few lackluster evolutionary reasons why it would be biologically adaptive for women to know which men aren't worth the trouble and for men to know who's not really a sexual competitor. But they also acknowledge that it's impossible to know from these findings what exactly it is about these facial features that give gays away. "Future studies," the authors wrote, "may wish to examine what aspects of these features lead to accurate judgments, what their origins might be, and how we acquire the ability to detect them."
I was curious enough about Rule's findings to look up "gay face" in the Urban Dictionary, a popular Web site that offers informal, user-contributed definitions of everyday (often crass) sayings. I like the Urban Dictionary because it captures people's understanding and use of words and phrases independent of their actual meaning; it's therefore as much a gauge of human psychology as it is a compendium of slang. There were several definitions of "gay face," including this derogatory doozy:
"A man, usually homosexual, with a distinctly effete facial structure with some very specific features; a strong jawline [sic] that lacks prominence, space between the eyes that recall people with down syndrome [sic], and a sloping, long forehead."
Now, that one's rather silly and sensationalized—even politically suspect—and there's certainly no scientific evidence in support of these claims about the "mongoloid" features of homosexual men's faces. But perhaps there is a kernel of truth to another definition of "gay face" in the Urban Dictionary:
"Gay men do not differ from straight men in the size and shape of any facial feature. Rather, the use of certain expressions can become ingrained in the musculature of the face over time. Since effeminate gay men utilize similar facial expressions as women, they develop female aging and muscle contraction patterns in their face. For example, gay face includes tightness around the mouth from pursing the lips, a facial expression common to gay men and women—but not to heterosexual men. Also, gay men are more emotionally expressive, leading to a general 'tightness' and muscular activation throughout the entire face. Gay face includes an eye expression that is both surprised-looking and predatory. Eyebrows are usually arched higher than that of straight men, and eyebrow hair is manicured. There is often a slightly tan and/or leathery look to the skin, especially among older gay men. Lesbians also have a version of gay face that emulates the facial muscular usage patterns of straight men. They exhibit an underexpression of emotion, relaxed brows, relaxed eyes, and less taut mouth and cheek muscles than straight women. The skin is usually pale and splotchy."

Again, a tad derogatory—but that doesn't mean there isn't some logic there, as well. On the one hand, the "muscular activation hypothesis" seems plausible enough to me. But on the other hand, remember that Rule and his co-authors largely controlled for these superficial giveaways in their stimulus photos. For example, in the second experiment, participants could still ferret out the gay face when shown the eye region sans eyebrows and cropped to the outer canthi. And I'm not entirely sure how to fashion—let alone scientifically operationalize—a "surprised-looking and predatory" eye expression. I think I would get a headache if I attempted that.

In addition, contrary to this urban definition, there may indeed be subtle, yet presently unknown, differences between gay and straight faces. (For example, one of my PhD students, David Harnden-Warwick, has a casual hunch that gay men may have sharper, clearer irises than straight men.) If so, this would add to a growing list of physiological and biological markers of sexual orientation. It was only a few years ago that researchers discovered that, unlike straight men, gay men tend to have hair whorl patterns that run in a counterclockwise direction. Such differences may evade conscious detection while registering at some level in people's social awareness.

All we know at the moment is that there's something endemic to our faces (in particular, our eyes and mouths) that betrays our "hidden" sexual orientation.

In this new 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 onFacebook and never miss an installment again.



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