After studying scans from 90 volunteers, the researchers found that straight women and gay men had no difference between the size of the different halves of their brain while lesbian women and straight men shared a particular "asymmetry" in their hemisphere size. In heterosexual men, the scans showed the right side of the brain to be typically 2% larger than the left compared to 1% in lesbians.
This is the first time scientists have used brain scanners to try to look for the source of those differences although earlier research had identified differences in spatial and verbal abilities related to sex and sexual orientation. Gay men and straight women have been found to fare better at certain language tasks, while heterosexual men and lesbians tend to have better spatial awareness.
The Swedish researcher, Ivanka Savic from the Stockholm Brain Institute, says she and her colleagues chose to measure areas of the brain likely to have been fixed at birth.
"This is the most robust measure so far of cerebral differences between homosexual and heterosexual subjects That was the whole point of the study, to show the parameters that differ, but which couldn't be altered by learning or cognitive processes," Savic was quoted by abc7news.com as saying.
The study noted similar characteristics in the area of the brain responsible for emotion response. In heterosexual men and lesbian women, there were more nerve "connections" in the right side of the amygdala, compared with the left. The reverse, with more neural connections in the left amygdala, was the case in homosexual men and straight women. However neuroscientists are unsure whether the similarities are genetic or develop in the womb.
Savic's team has yet to confirm whether the differences in brain shape are responsible for sexual orientation, or are a consequence of it. To find out, they have begun another study to investigate brain symmetry in newborn babies, to see if it can be used to predict their future sexual orientation.
Above: Images showing the amygdala in heterosexual men and women (labeled HeM and HeW) and homosexual and women (labeled HoM and HoW). Image: National Academy of Sciences, PNAS.
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Reader's Comments
and exciting discoveries all at the same time!
I just hope we dont lose our individualities,
lest be sooner or later morphed into color-coded bar-code identities.
Think of the cult-films Soylent Green,and Boys from Brazil.
AND Gattaca, thats real scary.
Moreover, are most of the female participants more to the masculinity side or feminine side? And vice versa for the male participants? These play an important role and may affect the findings as well.
Nevertheless, it is a great step and a stepping stone to further discover new findings about us. =D
While a few minds may never change their belief of gay people, many more are open to changing their minds in the face of reasonable facts, and this new evidence is certainly one in our favor.
Congratulations to our Californian brothers and sisters on the day of their marriages!
But it's more inconvenient scientific evidence for those that want to interpret the Bible in an intolerant way, to suit their own prejudices.
I hope it doesn't lead to certain cultures that already kill girl babies, also killing newborn gay babies.
but i dont see any connection and correlation between sexual orientation with brain size or structures of the brain itself, including activities of the brain's which associated with the behaviour as mentioned above ( directly or indirectly)
larger part of the brain doesnt have any correlation with the higher activities of that part itself
so i suppose to wait for more researches about that issue and not just based on this superficial incompleted research that actually can make people confused
On another side, as MMX44264 recalled, the Nazis had great fun with eugenism (mind you, they even deported pink triangles...)
nevertheless interpreting those photos it appears that on average we use more brain than anyone else - proof that we are genetically superior ... where are the our armies ... time to take over the world
So, when will we be "treated" and/or "cured" of our abnormalities / deficiencies with he help of the well organised and so rich mafia medical industry unless we are put in rehabilitation camps!
You bet some governments are going to use these precious results for homophobic purposes!
The article on the other hand uses typical journalistic hyperbole to skew the very general language of the actual study into more news worthy sounds. That is all too common as well.
Disundi, I don't see how you can claim that science has libeled anyone in this case. It has merely shown correlation between one thing and another. It has not claimed an abnormality only noted an apparent difference. And knowledge can hardly be libelous.
Will scientific evidence supporting nature for example solve this problem? Not immediately (I'm not naive). But the evidence will allow our community to push for equality in the developed world. And I think we will be able to get through the society armed with knowledge. And that trend will eventually trickle down to other part so the world.
As for evidence to the contrary (of nature). Well at least we'll know the battle lines are drawn.
salesmen :p
And to me, this study has an interesting parallel to the one conducted on left-handed people previously (In 2007, researchers discovered LRRTM1, the first gene linked to increased odds of being left-handed). Such studies are by itself actually harmless; it is only when harnessed with people who have issues with the targeted group o that it starts to get really ugly.
Don't go there. Please just don't.
Looking at the study, they picked up 25 straights and 20 gays of each sex, which makes up 90:
- Can anyone guess why the DISsymmetry?
- Some people identify as gay, others as straights, and the Kinsey studies taught us that most people are in the middle. How did they pick their sample up?
- They claim that brains of homosexual ppl look like those of heterosexual ppl of the opposite sex. I learned that there is a (not minor) difference between sexual orientation and gender orientation. Did they take care
of this issue?
- The Scientific American article says: "The team next used PET (positron emission tomography) scans to measure the blood flow to the amygdala, that part of the brain controlling emotion, fear and aggression (...) They found that in gay men and women, the blood flowed to areas involved in fear and anxiety, whereas in straight men and lesbians it tended to flow to pockets linked to aggression." I think fear and anxiety may lead quite easily to aggression, so what is the point? Would there be any stereotyping here?
You undermine yourself.
Who cares to fight an argument about whether we are born or become gay. We are gay. We can choose to be whatever.
I agree with other posters, the money is better spent on more important things than insecurities of how we got here.
People will still hate gays. You wanna be loved and hugged by straight homophobes?
You think blacks want to prove that they are born black and not become black? People still hate different races just because they are different.
Or there will be classes of gays:
1. pure born
2. became gay
3. wanna be gay
4. semi gay
etc
etc
Please start a JOKE page and put 'news' like this there.
:-)
saying that this research is useless is just like saying why should we bother to find out whether the earth is spherical or flat, so long as we live on earth and are safe and sound?
i think we can do some resource allocation, some money for research, and some money for good works. anyway, you will always have the poor with you, no matter how many good works you did. this is an unequal world. face it.
Interesting points you've raised, esp. with rgds to sexual & gender orientation. Indeed that is what most people are confused by.
But one very important point to note-
the people conducting this study are neither yr average Joe-in-the-street nor some quack pseudo-professionals- they are actual research scientists from the SBI . If it's credibility you are after, then yes- they have it. Just check out the Scientific Method & look at the tough myriad of processes involved in scientific research.
The only problem is when such studies are being over-simplified for the masses- turning them into
pseudo-science or pop psychology- or worse, marrying with the public's homophobic prejudices- that it cheapens & degrades the quality of such findings.
This may be even more funny: straight men are like gay women. It appears you missed that.
What's going on in our community? are we so focused on sex and porn all the time we can't see the difference between "being persecuted by old beliefs that says gay are worth living" and "trying to do noble things while still accepting the stigma that WE ARE NOT WORTH LIVING ourselves? in other words: we are being punish or we punish ourselves by thinking that we are worth to be punish?
These negative comments diminishing this the importance of this scientific finding are so pathetic.
There, is it enough awakening, now?
Hi, guys, lets put in extra efforts to increase our members in our community!
Being same sex addicted, is so wonderful, right?
homosexuality from a single research effort or an experiment. i understand your disappointment, but science doesn't work that way. it doesn't provide answers in the clear-cut way you would want it, it works in probabilities rather than absolutes, and every research
effort contributes to a better understanding, from which we can draw on to perform better experiments, ask new questions, validate or invalidate existing findings, which may eventually transform into better odds for said interpretation to be true.
so far, it seems that there is a partial biological basis for homosexuality. It is observed in 1500 species of animals, in those 500 is well documented http://news.bbc.co.uk/1/hi/world/europe/6066606.stm
It is useful for countering claims that homosexuality is unnatural, especially if used with a knowledge of evolutionary biology and psychology, but we must be careful not to derive a 'should' from an 'is' (cf natural fallacy) and hold homosexuality hostage to nature.
xenophobia and violent behaviour is 'natural' but not necessarily how we should behave.
this is a recent paper that might help put this article in perspective ('Born gay? The psychobiology of human sexual orientation' ) http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6V9F-4619GBX-1-1&_cdi=5897&_user=446477&_orig=search&_coverDate=06%2F30%2F2003&_sk=999659991&view=c&wchp=dGLbVlz-zSkWb&_valck=1&md5=df4669a61818057b247a1438fa84f5a9&ie=/sdarticle.pdf
Some papers you may find interesting:
Camperio-Ciani, A., Corna, F., & Capiluppi, C. (2004). Evidence for maternally inherited factors favouring male homosexuality and promoting female fecundity. Proceedings of the Royal Society of London, 271, 2217-2221.
Muscarella, F. (2002). Preferred partner characteristics in homosexual men in relation to speculated patterns of brain differentiation. Neuroendocrinology Letters, 23, 299-302.
Rahman, Q., & Wilson, G. D. (2003). Born gay? The psychobiology of human sexual orientation. Personality and Individual Differences, 34, 1337-1382.
Schmitt, D. P. (2006). Sexual Strategies Across Sexual Orientations: How Personality Traits and Culture Relate to Sociosexuality Among Gays, Lesbians, Bisexuals, and Heterosexuals. In M. R. Kauth (Ed.), Handbook of the Evolution of Human Sexuality (pp. 183-214). Binghamton, NY: Haworth Press.
How babies brain changes when they are gay as they grow up.
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