Researchers found that pupil dilation can now reveal a person’s sexual preference.
A new study from Cornell University found that when a person’s eyes are dilated and examined using a specialized infrared lens they can determine their sexual orientation.
Researchers examined the dilated pupils of study participants as they watched erotic videos.
Results found that a person’s pupils widened when a video featured people the participant was most attracted to, thereby revealing if they were heterosexual or homosexual.
Previous studies commonly relied on people talking about their sexual preferences or were based on genital arousal alone. These types of methods faced many 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," said 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."
Study results found that heterosexual men exhibited strong pupillary responses to women and very little to men. However, women showed pupillary responses to both sexes. These results prove, as did previous studies that women experience a different type of sexuality than men.
This new research also sheds light on men’s bisexuality. In former studies, bisexual men based their sexual identity on romantic and identity issues rather than physiological sexual arousal. However, the pupils of bisexual men in the most recent study responded to both men and women.
"We can now finally argue that a flexible sexual desire is not simply restricted to women — some men have it, too, and it is reflected in their pupils," said Ritch C. Savin-Williams, co-author and professor in Human Development at Cornell. "In fact, not even a division into 'straight,' 'bi,' and 'gay' tells the full story. Men who identity as 'mostly straight' really exist both in their identity and their pupil response; they are more aroused to males than straight men, but much less so than both bisexual and gay men."
Researchers believe the new findings can aid in understanding the two sexualities better while revealing a variety of sexualities that have gone ignored.