Secret to sexual orientation in the eyes

Pupil dilation may reveal a person's sexual orientation -- if you can get that close to someone without creeping them out.

Researchers reached that conclusion after measuring pupil dilation while study subjects -- who had previously answered questionnaires about their sexual orientation -- watched erotic videos. However, results were a bit dubious for women, who were observed with similar pupil dilation when they saw pornographic materials featuring either men or women, so take this study with a grain of salt.

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