Biology and Sexual Orientation

Hair Whorl Differences between Gay and Non-gay Men

I posted an article the other day on my discussion with owner of the Filipino grocery store on homosexuality triggered by our mutual love and enjoyment on watching a Pinoy TV drama titled My Husband's Lover. This prompted me to do an Internet search on the biology of sexual orientation. The following is a brief summary of my findings. If you want more detail information on this subject, read the website I have listed on the bottom of this page.

Physiological and Cognitive Differences of Gay versus Non-Gay Men and Lesbians

There are several studies that have found correlations between physiology of people and their sexuality. These studies provide evidence of both physiological(9 items) and cognitive( 2 items) differences between gay men, non-gay men and lesbians. The following are some findings I found interesting. It may be very controversial and not believable to some of you specially if you are homophobic.

Physiological

1.Gay men and straight women have, on average, equally proportioned brain hemispheres. Lesbian women and straight men have, on average, slightly larger right brain hemispheres.

2. Gay men report, on an average, slightly longer and thicker penises than non-gay men.

3. Gay men's brains respond differently to fluoxetine, a selective serotonin reuptake inhibitor.

4. The functioning of the inner ear and the central auditory system in lesbians and bisexual women are more like the functional properties found in men than in non-gay women (the researchers argued this finding was consistent with the prenatal hormonal theory of sexual orientation).

5. Gay and non-gay people's brains respond differently to two putative sex pheromones (AND, found in male armpit secretions, and EST, found in female urine).

6. The amygdala, a region of the brain, is more active in gay men than non-gay men when exposed to sexually arousing material.

7. Finger length ratios between the index and ring fingers may be different between non-gay and lesbian women.

8. A study of over 50 gay men found that about around 23% had counterclockwise hair whorl, as opposed to 8% in the general population. This may correlate with left-handedness.

9. Gay men have increased ridge density in the fingerprints on their left thumbs and pinkies.

Cognitive

The presence of subtle differences in the way gay people and non-gay people process certain kinds of information was suggested from a recent study. Researchers have found that:

1. Gay men and lesbians are more verbally fluent than heterosexuals of the same sex (but two studies did not find this result).

2. Gay men may receive higher scores than non-gay men on tests of object location memory (no difference was found between lesbians and non-gay women).

Reference: en.wikipedia.org/wiki/Biology_and_sexual_orientation‎