Hey! Do you smell something?
Gay Men Respond Differently to Pheromones... research points to biological involvement in sexual orientation.
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 Ontario, Canada.
Witelson, who was not part of the research team, said the findings clearly show a biological involvement in sexual orientation.
The study, published in Tuesday'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 derived from male and female sex hormones.
These chemicals are thought to be pheromones _ molecules known to trigger responses such as defense and sex in many animals.
Whether humans respond to pheromones has been debated, although in 2000 American researchers reported finding a gene that they believe directs a human pheromone receptor in the nose.
The Swedish study was one of a series looking at whether parts of the brain involved in reproduction differ in response to odors and pheromones, lead researcher Ivanka Savic said.
The brains of different groups responded similarly to ordinary odors such as lavender, but differed in their response to the chemicals thought to be pheromones, Savic said.
The Swedish researchers divided 36 subjects into three groups _ heterosexual men, heterosexual women and homosexual men. They studied the brain response to sniffing the chemicals, using PET scans. All the subjects were healthy, unmedicated, right-handed and HIV negative.
When they sniffed smells like cedar or lavender, all of the subjects' brains reacted only in the olfactory region that handles smells.
But 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.
The response in gay men and straight women was concentrated in the hypothalamus with a maximum in the preoptic area that is active in hormonal and sensory responses necessary for sexual behavior, the researchers said.
And when estrogen, the female hormone was used, there was only a response in the olfactory portion of the brains of straight women. Homosexual men had their primary response also in the olfactory area, with a very small reaction in the hypothalamus, while heterosexual men responded strongly in the reproductive region of the brain.
Savic said the group is also doing a study involving homosexual women but those results are not yet complete.
In a separate study looking at people's response to the body odors of others, researchers in Philadelphia found sharp differences between gay and straight men and women.
"Our findings support the contention that gender preference has a biological component that is reflected in both the production of different body odors and in the perception of and response to body odors," said neuroscientist Charles Wysocki, who led the study.
In particular, he said, finding differences in body odors between gay and straight individuals indicates a physical difference.
It's hard to see how a simple choice to be gay or lesbian would influence the production of body odor, he said.
Wysocki's team at the Monell Chemical Senses Center studied the response of 82 heterosexual and homosexual men and heterosexual and homosexual women to the odors of underarm sweat collected from 24 donors of varied gender and sexual orientation.
They found that gay men differed from heterosexual men and women and from lesbian women, both in terms of which body odors gay men preferred and how their own body odors were regarded by the other groups.
Gay men preferred odors from gay men, while odors from gay men were the least preferred by heterosexual men and women and by lesbian women in the study. Their findings, released Monday, are to be published in the journal Psychological Science in September.
The Swedish research was funded by the Swedish Medical Research Council, the Karolinska Institute and the Magnus Bergvall Foundation. Wysocki's research was supported by the Monell Center.
Reported by:
By RANDOLPH E. SCHMID
The Associated Press
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 Ontario, Canada.
Witelson, who was not part of the research team, said the findings clearly show a biological involvement in sexual orientation.
The study, published in Tuesday'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 derived from male and female sex hormones.
These chemicals are thought to be pheromones _ molecules known to trigger responses such as defense and sex in many animals.
Whether humans respond to pheromones has been debated, although in 2000 American researchers reported finding a gene that they believe directs a human pheromone receptor in the nose.
The Swedish study was one of a series looking at whether parts of the brain involved in reproduction differ in response to odors and pheromones, lead researcher Ivanka Savic said.
The brains of different groups responded similarly to ordinary odors such as lavender, but differed in their response to the chemicals thought to be pheromones, Savic said.
The Swedish researchers divided 36 subjects into three groups _ heterosexual men, heterosexual women and homosexual men. They studied the brain response to sniffing the chemicals, using PET scans. All the subjects were healthy, unmedicated, right-handed and HIV negative.
When they sniffed smells like cedar or lavender, all of the subjects' brains reacted only in the olfactory region that handles smells.
But 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.
The response in gay men and straight women was concentrated in the hypothalamus with a maximum in the preoptic area that is active in hormonal and sensory responses necessary for sexual behavior, the researchers said.
And when estrogen, the female hormone was used, there was only a response in the olfactory portion of the brains of straight women. Homosexual men had their primary response also in the olfactory area, with a very small reaction in the hypothalamus, while heterosexual men responded strongly in the reproductive region of the brain.
Savic said the group is also doing a study involving homosexual women but those results are not yet complete.
In a separate study looking at people's response to the body odors of others, researchers in Philadelphia found sharp differences between gay and straight men and women.
"Our findings support the contention that gender preference has a biological component that is reflected in both the production of different body odors and in the perception of and response to body odors," said neuroscientist Charles Wysocki, who led the study.
In particular, he said, finding differences in body odors between gay and straight individuals indicates a physical difference.
It's hard to see how a simple choice to be gay or lesbian would influence the production of body odor, he said.
Wysocki's team at the Monell Chemical Senses Center studied the response of 82 heterosexual and homosexual men and heterosexual and homosexual women to the odors of underarm sweat collected from 24 donors of varied gender and sexual orientation.
They found that gay men differed from heterosexual men and women and from lesbian women, both in terms of which body odors gay men preferred and how their own body odors were regarded by the other groups.
Gay men preferred odors from gay men, while odors from gay men were the least preferred by heterosexual men and women and by lesbian women in the study. Their findings, released Monday, are to be published in the journal Psychological Science in September.
The Swedish research was funded by the Swedish Medical Research Council, the Karolinska Institute and the Magnus Bergvall Foundation. Wysocki's research was supported by the Monell Center.
Reported by:
By RANDOLPH E. SCHMID
The Associated Press
This entry was posted
on Monday, May 09, 2005 at 4:27 PM.
Want to discuss? Leave a comment below.
ByHow come people on the left insist that gays are "born different" but when someone (say the president of Harvard)suggests that boys and girls are different the whole liberal establishment is outraged?
Daniel's Political Musings
By
Boys and girls ARE different. It is not the left nor the right. It may be the extreme religious right (you) vs. the rest of society in this thought that gays and lesbians are not born gay. Science is pointing more and more towards this. Although you probably would not believe science if it were 100% proven that it is the case that we are born gay.
Also - you are taking what the President of Harvard said completely out of context...
"President Summers caused a firestorm with remarks at a January conference suggesting biological differences may partly explain why fewer women reach the very highest-level science jobs. He has repeatedly apologized for those remarks."
Here is a letter from Mr. Summers regarding his statement:
View it here
By
Oh and Daniel - why is it that when science points to the fact that gays and lesbians are in fact born gay - the religious 'establishment' is outraged?
I am pretty sure that it wasn't the "whole liberal establishment" that was "outraged". I'm sure that there were plenty of woman who are on the right who disagreed with him.
You and your over generalizations... Don't you have to go now and bitch on your own blog how about every else who is different than you is wrong? I'm sure you can talk about your hatred of Mexicans, gays and blacks some more. You never seem to get tired of that...
By
Wow, I am the "extreme religious right?" I always wondered who they were.
So if science says that "gender dysphoria" is a mental disorder do you agree?
How is it that "gay" men have wives and children before they "come out?" Not being gay I couln't imagine having sex with a man. How could a "gay" man have sex with a woman? Wouldn't that disgust them? Wouldn't you think that it works both ways?
What do you call what you do on your blog when you insist everyone who is different than you is wrong? When you talk about your "hatred" of Christians?
Have a nice night!
By
Daniel - you've got some major issues. A.) I do not have a hatred of Christians. I was brought up in a Christian household, went to Christian school etc. I just have a huge issue with the radicals. The ones who stifle our civil rights. These are things that we will never agree with each other on.
I will respond to your additional comments in the AM. I need to get some sleep. Long day at work. What do you do for work Daniel?
By
You know, it always just comes down to the "I can't imagine having sex with a man" statement by the straight guys, doesn't it? There's a lot of things we may not understand, but respecting our differences, is one way we might start. Daniel is what I call a hater: he hates immigrants, he hates gays, he hates cultural diversity. In his world, he'd prefer an all white, straight community, just like him. My worst nightmare.
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