We are all familiar with the saying 'beauty is in the eye of the beholder', but it turns out that your sexual orientation can be seen in your eyes. 

Dr Gerulf Rieger, lecturer in the Department of Psychology at Essex University, has been working on experiments to measure people's sexual orientation for fourteen years.

It is very simple for someone to tell you their sexual orientation, but actually scientifically finding that out is a tricky proposition. One method involved putting a high-tech elastic band on a man's genitalia and showing him photos and videos of other men and women engaging in different levels of sexual acts and then measuring how aroused the man is towards specific genders.

A similar experiment also exists for women too!

Quite often, the results do not reflect what the subject believes their sexuality to be. According to Dr Rieger, straight people can be attracted to others of the same sex, and bisexuals can generally find themselves attracted to one gender more than the other.

Another method Rieger has come up with to measure arousal is to examine the dilation of a person's pupils.

He has even come up with a controversial way of examining children's masculinity/femininity to determine whether they will be gay or straight in their adult life and claims his results have been very accurate so far.

We'll be speaking to Dr Rieger on Futureproof, this Saturday at 10am for what promises to be a fascinating show!

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