New Study Shows Sexual Orientation Revealed by One’s Eyes

A new study reveals that sexual orientation can be detected by looking at the pupils of our eyes.

EyeScience Daily reports:

For the first time, researchers at Cornell University used a specialized infrared lens to measure pupillary changes to participants watching erotic videos. Pupils were highly telling: they widened most to videos of people who participants found attractive, thereby revealing where they were on the sexual spectrum from heterosexual to homosexual.

The findings were published August 3 in the scientific journal PLoS ONE.

Previous research explored these mechanisms either by simply asking people about their sexuality, or by using physiological measures such as assessing their genital arousal. These methods, however, come with substantial problems.

"We wanted to find an alternative measure that would be an automatic indication of sexual orientation, but without being as invasive as previous measures. Pupillary responses are exactly that," says Gerulf Rieger, lead author and research fellow at Cornell. "With this new technology we are able to explore sexual orientation of people who would never participate in a study on genital arousal, such as people from traditional cultures. This will give us a much better understanding how sexuality is expressed across the planet."

Justin Lehmiller adds:

The idea for this study came out of past research indicating that our pupils naturally dilate when we see something interesting. This is an involuntary response activated by our autonomic nervous system, a bodily system that controls breathing, digestion, heart rate, and many other automatic processes. Pupil dilation is therefore something that it unlikely to be under a person’s conscious control. One previous study conducted in the 1960s found that people’s pupils tend to dilate when they see sexually arousing imagery, but that study only looked at a total of 10 participants (half heterosexual and half homosexual), all of whom were men.

In the new study, 325 men and women of varying sexualities (heterosexual, homosexual, and bisexual) watched a series of one-minute video clips in random order. The video content was either a man masturbating, a woman masturbating, or a neutral landscape. A gaze-tracking camera measured the size of participants’ pupils every two milliseconds as the videos were shown. All videos were of equivalent brightness to ensure that changes in light did not affect pupil size.


  1. simon says

    “With this new technology we are able to explore sexual orientation of people who would never participate in a study on genital arousal, such as people from traditional cultures. This will give us a much better understanding how sexuality is expressed across the planet.”
    These people from traditional cultures also will not watch porns in front of the researchers.

  2. Derrick from Philly says

    Cool! I was a participant in this study. It’s cool to see the results now.

    Hush, CAM. You wouldn’t want your mother to find out that her baby boy does porn for scientific studies.

    But what exactly did you do to make people’s pupils pop?

  3. Yeek says

    The problem with this approach is that eyes also dilate when you are freaked out by something. “Interested” could also reply to people who were surprised or horrified.

  4. Icebloo says

    Which idiot decided to make this public ? This method can now be used by terrible governments to find gay people and maybe torture or kill them ! Way to go morons !

  5. Jay-Squiggle says

    This “technology” was used in Canada in the 60s to root out queers from the country’s government, the RCMP, and the military. They called it…THE FRUIT MACHINE. I’m not kidding.

  6. GregV says

    I’ve always assumed that studying eye response could correctly identify sexual orientation (and it need not be to porn). For example, I can imagine if a researcher had taken me in kindergarten and showed me a photo of a group of people which included a remarkably handsome man and pretty woman. I have no doubt my eyes would have scanned the faces and then lingered to study the handsome man’s face. I’m quite sure that such a study, if followed up on three decades later, would show a strong correlation to adult sexual orientation.

    Like others, I do have concerns on how this could be misused by homophobes.

    It is also laughable to think that “people from traditional cultures” who would not consent to measuring their erectile response would automatically have no problem consenting to having their pupil’s response measured while they watch people masturbating.

  7. Paul R says

    I think the sentiment that governments or churches will somehow be able to impose this technology is strangely paranoid. You honestly think that they’re going to start showing porn to every citizen and assessing their responses? Even Iran, North Korea, and Uganda aren’t going to do that. They prosecute behavior, not desire or intent.

    The notion of “rounding up the gays” pretty much died out a few decades ago aside from the most backward regimes.

  8. Randy says

    I have no problems with the religious right using it to expose gays, so long as they use it on themselves. The law should be that those who are most anti-gay are the first ones to have to prove they are not gay themselves.

    You do that, and they’ll back off immediately.

  9. jason says

    Yet another silly study which uses pornography and voyeurism as a basis for research into human sexual orientation. It’s garbage. What you find attractive in a voyeuristic sense does NOT define how you are oriented sexually in the real world sense. Interacting sexually with another human being is defined completely differently from what you like to watch.

    For instance, I might like to look at a picture of the Mona Lisa but I’m not going to want to copulate with it.

  10. Rovex says

    There is a problem with this. I was talking to a friend in my local uni about it, He said that there was similar research that suggested that while it was vaguely accurate there was interference from the ‘fight or flight’ response. Some gay men would have a ‘fight’ reaction to the imagery of a woman that caused their pupils to dilate. The same could be said about straight men exposed to a males image. No sexual attraction, just an adverse reaction brought on my a perceived rival.

  11. Stefan says

    I have a hard time understanding the point of funding studies that have no clear policy effects or other benefits. Some might think this contributes to the “gay is not a choice” position, but this merely tells us that someone has a physiological sexual response measurable in the eyes. This seems to fall in the growing category of “interesting but ultimately useless science.”

Leave A Reply