We read faces every day for clues to gauge the reactions of others and better understand the world around us. And more often than not, we fall in love with a face, only secondarily the rest of the person. New research has teased out yet another way in which gays and lesbians differ from their heterosexual counterparts in processing this information.
A team at the University of Zurich in Switzerland used functional magnetic resonance imaging ( fMRI ) to take snapshots of brain activity while the subjects looked at photographs of men's and women's faces. Faces expressing strong emotions such as happiness or fear generate greater activity within the brain.
They hypothesized that individuals adopted 'face reading' strategies that are different for potential sexual partners than for others with whom they interact, and that this would be reflected in different patterns of brain activity. For most men, this would mean a stronger brain reaction to photos of women, and the reverse for most women.
They tested it on 40 subjects, 10 each of self-identified heterosexual men and women, and gay men and lesbians. Each was shown the same set of photos and asked to rate the face as attractive, neutral or unattractive, while their brain activity was being scanned by the fMRI.
There was a wide consensus on which photos were rated attractive and unattractive, suggesting a shared set of values of what constitutes beauty that cross lines of gender and sexual orientation. And they all showed similar patterns of activity in those sections of the brain that process visual images.
But the patterns of activity differed markedly in the 'reward centers' of the brain that reflect a potential sexual partner. Heterosexual women and homosexual men exhibited a significantly greater response to male faces, whereas, heterosexual men and homosexual women responded significantly more to female faces.
The study was published in the Jan. 10 edition of Current Biology. It did not suggest whether these differences were genetic in nature, occurred during development in the womb, or are shaped by later experience.
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A well-lubricated finger up the butt, the digital rectal exam, is a standard screen for prostate cancer. Most straight men loathe it and even gay men who might enjoy the 'exam' in a different setting may be apprehensive if they are not out to their physician.
They go through the procedure because prostate cancer is the second leading cause of cancer deaths in men, more than 30,000 a year. Screening for early detection should be a good thing. But a new study challenges that assumption.
It identified 501 patients diagnosed with prostate cancer at 10 Veterans Affairs hospital centers in New England between 1991 and 1995 who had died by the end of 1999, and it matched them against living veterans who were similar in terms of age and other health conditions. It examined the medical records of both groups to see who had and had not been screened for prostate cancer.
If screening helped to prevent or delay death, then those who were still alive should have been more likely to have been screened for the disease than those who had died. But they were not; the rates of screening were 13 and 14 percent, respectively. The authors concluded that while screening can detect prostate cancer earlier, it does not necessarily prolong survival.
Dr. Michael J. Barry of Massachusetts General Hospital added in an accompanying editorial, aggressive surgical treatment of prostate cancers 'has a modest benefit … that comes at a considerable price in terms of sexual dysfunction and incontinence.'
Both articles appear in the Jan. 9 issue of the Archives of Internal Medicine, published by the American Medical Association.
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National Blood Donor Month is January, but it doesn't mean much to the GLBT community because the official policy bans donation by men who have had sex with another man at any time since 1977. Just once is enough to get you banned for life.
The policy initially was put in place in 1985, immediately after HIV was identified as the cause of AIDS. Knowledge was limited and the test to screen blood was crude, so it made sense to err on the side of caution.
The FDA reconsidered its donation guidelines in 2000. Its staff felt that our knowledge of HIV and screening technology had improved significantly. They recommended changing the restriction to allow gay men to donate if they have been sexually abstinent or in a monogamous relationship for the last 12 months. The association of professionals in the blood industry and the association representing local organizations that annually collect about half the nation's blood donations each supported the change at a public meeting held by the FDA in 2000. Only the Red Cross supported maintaining the lifetime ban. The FDA blinked and did not change the policy, the ban remains.
However, many gay men still donate blood, they simply lie on the questionnaire. And many choose to avoid the Red Cross, which makes money off of the processing and handling of blood. They make their donations through other organizations that are members of the American Association of Blood Banks.
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'Marijuana munchies' are one of the most common side effects of using the popular herb. The principle has been put to good use in treating wasting syndrome associated with advanced HIV disease and the side effects of cancer chemotherapy. Now researchers at Columbia University reveal just how the process works.
The cannabinoid receptor 1 ( CB1 ) is located primarily in the brain and is triggered by natural regulatory molecules called endocannabinoids. Focusing on the lateral hypothalamus, the section of the brain known to control food intake, Young-Hwan Jo and colleagues found that THC, an active component of pot, disrupts the normal signaling process of other molecules in the brain, including leptin.
Leptin tells your body that it is full and should stop eating. Mice who have been genetically altered to be deficient in leptin don't know when to stop eating and become obese. The end result of this complex biochemistry is new insights into how hunger/fullness signals play out in the brain. It may lead to new drugs to help regulate the craving for food and thus help people lose weight.
The information above is provided as education, not as diagnosis or treatment. All healthcare decisions should be made in consultation with your doctor.
