Brains of gays, straights react differently: Study
RANDOLPH E. SCHMID, ASSOCIATED PRESS
WASHINGTON—Gay men's brains respond differently from those of heterosexual males when exposed to a sexual stimulus, researchers have found.
The homosexual men's brains responded more like those of women when the men sniffed a chemical from the male hormone testosterone.
"It is one more piece of evidence ... that is showing that sexual orientation is not all learned," said Sandra Witelson, an expert on brain anatomy and sexual orientation at the Michael G. DeGroote School of Medicine at McMaster University in Hamilton.
Witelson, who was not part of the research team, said the findings clearly show a biological link in sexual orientation.
The study, published in today's issue of Proceedings of the National Academy of Sciences, was done by researchers at the Karolinska Institute in Stockholm, Sweden.
They exposed heterosexual men and women and homosexual men to chemicals from male and female sex hormones.
These chemicals are thought to be pheromones — molecules known to trigger responses such as defence and sex in animals.
The researchers divided 36 subjects into three groups — heterosexual men, heterosexual women and homosexual men. All of them were unmedicated, right-handed and HIV-negative.
Researchers studied their brain response to sniffing the chemicals, using PET scans.
The brains of different groups responded similarly to ordinary odours such as lavender, but differed in their response to the chemicals thought to be pheromones, Savic said.
When they sniffed smells like cedar or lavender, all of the subjects' brains reacted only in the olfactory region that handles smells.
When confronted by a chemical from testosterone, the male hormone, portions of the brains active in sexual activity were activated in straight women and in gay men, but not in straight men, the researchers found.
This finding still need to be tested for reproducibility. This kind of black/white result is some how questionable if one think about those who are in between, bisexual etc...I do not think that the biochemistry is so simple...may be I am wrong... Sometimes you have such Hype announcements for quick promotion....
"Hé ! bonjour, Monsieur du Corbeau.
Que vous êtes joli ! que vous me semblez beau !
Sans mentir, si votre ramage
Se rapporte à votre plumage,
Vous êtes le Phénix des hôtes de ces bois."
chargement...
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