Wednesday, June 18, 2008

SSA AND THE BRAIN

This adds a little more evidence that SSA has a biological basis:

"Gay men and straight women have similar brains, study says
The research suggests a basic biological link between sexual orientation and a range of mental functions.

By Denise Gellene, Los Angeles Times Staff Writer June 17, 2008 http://www.latimes.com/la-sci-gaybrain17-2008jun17,0,6828157.story

The brains of gay men resemble those of straight women, according to research published today that provides more evidence of the role of biology in sexual orientation.Using brain-scanning equipment, researchers said they discovered similarities in the brain circuits that deal with language, perhaps explaining why homosexual men tend to outperform straight men on verbal skills tests -- as do heterosexual women.

What does gay look like? Science keeps trying to figure that out
The area of the brain that processes emotions also looked much the same in gay men and straight women -- and both groups have higher rates of depressive disorders than heterosexual men, researchers said.The study in Proceedings of the National Academy of Sciences, however, found that the brain similarities were not as close in the case of gay women and straight men.Previous studies have found evidence that sexual orientation is influenced by biological factors. More than a decade ago, neurobiologist Simon LeVay reported that a key area of the hypothalamus, a brain structure linked to sexual behavior, was smaller in homosexual men than in heterosexual men.The latest study, led by Dr. Ivanka Savic of the Karolinska Institute in Stockholm, was significant in that it looked at areas of the brain that have nothing to do with sexual behavior, suggesting that there was a basic biological link between sexual orientation and a range of brain functions."The question is, how far does it go?" said Dr. Eric Vilain, who studies human sexual development at UCLA and was not involved in the study. "In gay men, the brain is feminized. Is that limited to particular areas, or is the entire brain female-like?"Vilain said his hunch was that the entire brain was not feminized because "gay men have a number of masculine traits that are not present in women." For example, he said, men regardless of sexual orientation tend to be interested in casual sex and are stimulated by sexually suggestive images.Savic and her colleagues used magnetic resonance imaging to measure brain volumes of two groups, each divided evenly between men and women: 50 heterosexuals and 40 homosexuals. They knew going into the study that in men the right cerebral hemisphere is larger than the left, but in women the hemispheres are of equal size.The results showed that gay men had symmetrical brains like those of straight women, and homosexual women had slightly asymmetrical brains like those of heterosexual men. Symmetry is thought to favor verbal skills, the report said.The differences were pronounced. For example, the right cerebral hemisphere in heterosexual men was 624 cubic centimeters -- 12 cubic centimeters greater than the left side. In homosexual men, the right hemisphere was 608 cubic centimeters -- 1 cubic centimeter smaller than the left.In heterosexual women, there was no volume difference between right and left hemispheres. But in homosexual women, their right hemisphere was 5 cubic centimeters larger than the left.Next, researchers used positron emission topography to measure blood flow in the amygdala, a brain area involved in processing emotions. The circuitry of the amygdala in gay men more closely resembled that of straight women than straight men, researchers said. The amygdalas of gay women looked more like those of straight men, the report said.Savic said she thought the brain differences originated in the womb or infancy, probably as a result of genetic or hormonal factors. She said she could not explain why the differences were more pronounced in homosexual men than in homosexual women.S. Marc Breedlove, a Michigan State University neuroscientist who studies sexual development, said that in his studies with rats, changes in prenatal levels of testosterone caused the sort of brain alterations that Savic observed.denise.gellene@latimes.com "

7 comments:

santorio said...

so i have a "feminized brain?"

somehow, that isnt' exactly how i want to define myself...

Sean said...

when i was in college this was one of the areas of interest for me. fortunetly i had a professor who was a neurobiologist (and mormon), he would often talk about the Sexually Dymorphic Neuculei (SDN) of the male and female brain. This was first discovered during the 1960s - at the time that i was at college it was only just a hypothosis that males of the same gender orientation may have a "feminized brain" as a result of severe stress during gestation.
It is a fascinating study. I will have to contact some friends to see what else has been discovered.

what i see as the moral or ethical questions resulting from a "feminized" brain for same sex oriented individuals would be (1) is this result seen by the individual as a "blessing" or a "hinderence"?, (2) do they desire it "fixed" or are they happy with who they are? additionally i would ask "should it be fixed?" does this feminization necessarily mean that the body is defective? or has it been created the way we are inside?

love to chat with you more about it.

DA-FUN said...

Great information! Keep them coming...

jonathan said...

I don't know if you're still maintaining your blog, but I followed a link here from your comment on "Finding Faith in Christ and the Members" over on The LDS Left Blog. Really my comment here is more a response to what you posted there, which I think expresses something that needs to be understood more widely.

--Jonathan Langford, author of "No Going Back" (first novel I'm aware of that stars a gay kid who also happens to be a regular Mormon)

gentlefriend said...

Thank you Jonathan. I will check out the book.

gentlefriend said...

Sean, thanks for you comment. We can chat at gentlefriend@ca.rr.com .

gentlefriend said...

I can now be reached at truefriend111@ca.rr.com.