bob_garwood

http://www.nytimes.com/2011/08/23/health/23bisexual.html

No Surprise for Bisexual Men: Report Indicates They Exist
By DAVID TULLER

In an unusual scientific about-face, researchers at Northwestern University have found evidence that at least some men who identify themselves as bisexual are, in fact, sexually aroused by both women and men.

The finding is not likely to surprise bisexuals, who have long asserted that attraction often is not limited to one sex. But for many years the question of bisexuality has bedeviled scientists. A widely publicized study published in 2005, also by researchers at Northwestern, reported that “with respect to sexual arousal and attraction, it remains to be shown that male bisexuality exists.”

That conclusion outraged bisexual men and women, who said it appeared to support a stereotype of bisexual men as closeted homosexuals.

In the new study, published online in the journal Biological Psychology, the researchers relied on more stringent criteria for selecting participants. To improve their chances of finding men aroused by women as well as men, the researchers recruited subjects from online venues specifically catering to bisexuals.

They also required participants to have had sexual experiences with at least two people of each sex and a romantic relationship of at least three months with at least one person of each sex.

Men in the 2005 study, on the other hand, were recruited through advertisements in gay-oriented and alternative publications and were identified as heterosexual, bisexual or homosexual based on responses to a standard questionnaire.

In both studies, men watched videos of male and female same-sex intimacy while genital sensors monitored their erectile responses. While the first study reported that the bisexuals generally resembled homosexuals in their responses, the new one finds that bisexual men responded to both the male and female videos, while gay and straight men in the study did not.

Both studies also found that bisexuals reported subjective arousal to both sexes, notwithstanding their genital responses. “Someone who is bisexual might say, ‘Well, duh!’” said Allen Rosenthal, the lead author of the new Northwestern study and a doctoral student in psychology at the university. “But this will be validating to a lot of bisexual men who had heard about the earlier work and felt that scientists weren’t getting them.”

The Northwestern study is the second one published this year to report a distinctive pattern of sexual arousal among bisexual men.

In March, a study in Archives of Sexual Behavior reported the results of a different approach to the question. As in the Northwestern study, the researchers showed participants erotic videos of two men and two women and monitored genital as well as subjective arousal. But they also included scenes of a man having sex with both a woman and another man, on the theory that these might appeal to bisexual men.

The researchers — Jerome Cerny, a retired psychology professor at Indiana State University, and Erick Janssen, a senior scientist at the Kinsey Institute — found that bisexual men were more likely than heterosexuals or gay men to experience both genital and subjective arousal while watching these videos.

Dr. Lisa Diamond, a psychology professor at the University of Utah and an expert on sexual orientation, said that the two new studies, taken together, represented a significant step toward demonstrating that bisexual men do have specific arousal patterns.

“I’ve interviewed a lot of individuals about how invalidating it is when their own family members think they’re confused or going through a stage or in denial,” she said. “These converging lines of evidence, using different methods and stimuli, give us the scientific confidence to say this is something real.”

The new studies are relatively small in size, making it hard to draw generalities, especially since bisexual men may have varying levels of sexual, romantic and emotional attraction to partners of either sex. And of course the studies reveal nothing about patterns of arousal among bisexual women. The Northwestern study included 100 men, closely split among bisexuals, heterosexuals and homosexuals. The study in Archives of Sexual Behavior included 59 participants, among them 13 bisexuals.

The new Northwestern study was financed in part by the American Institute of Bisexuality, a group that promotes research and education regarding bisexuality. Still, advocates expressed mixed feelings about the research.

Jim Larsen, 53, a chairman of the Bisexual Organizing Project, a Minnesota-based advocacy group, said the findings could help bisexuals still struggling to accept themselves.

“It’s great that they’ve come out with affirmation that bisexuality exists,” he said. “Having said that, they’re proving what we in the community already know. It’s insulting. I think it’s unfortunate that anyone doubts an individual who says, ‘This is what I am and who I am.’ ”

Ellyn Ruthstrom, president of the Bisexual Resource Center in Boston, echoed Mr. Larsen’s discomfort.

“This unfortunately reduces sexuality and relationships to just sexual stimulation,” Ms. Ruthstrom said. “Researchers want to fit bi attraction into a little box — you have to be exactly the same, attracted to men and women, and you’re bisexual. That’s nonsense. What I love is that people express their bisexuality in so many different ways.”

Despite her cautious praise of the new research, Dr. Diamond also noted that the kind of sexual arousal tested in the studies is only one element of sexual orientation and identity. And simply interpreting results about sexual arousal is complicated, because monitoring genital response to erotic images in a laboratory setting cannot replicate an actual human interaction, she added.

“Sexual arousal is a very complicated thing,” she said. “The real phenomenon in day-to-day life is extraordinarily messy and multifactorial.”

http://www.npr.org/2010/12/01/131698228/overeating-like-drug-use-rewards-and-alters-brain

If you've ever wondered why it's hard to stay on a diet, consider this observation from Ralph DiLeone, a brain scientist at Yale University: "The motivation to take cocaine in the case of a drug addict is probably engaging similar circuits that the motivation to eat is in a hungry person."

That's what brain scientists have concluded after comparing studies of overeating with studies of drug addiction, DiLeone says.

They've also found that, at least in animals, sweet or fatty foods can act a lot like a drug in the brain, he says. And there's growing evidence that eating too much of these foods can cause long-term changes in the brain circuits that control eating behavior.

The food-drug link comes from the fact that both animal and human brains include special pathways that make us feel good when we eat, and really good when we eat sweet or fatty foods with lots of calories, DiLeone says.

"Drug addiction is really hijacking some of these pathways that evolved to promote food intake for survival reasons," he says

That doesn't necessarily mean food is addictive the way cocaine is, DiLeone says, but he says there is growing evidence that eating a lot of certain foods early in life can alter your brain the way drugs do.

Food That Changes The Brain

Teresa Reyes, a research assistant professor in the Department of Pharmacology at the University of Pennsylvania, showed that in an experiment with mice.

Drug addiction is really hijacking some of these pathways that evolved to promote food intake for survival reasons.
- Ralph DiLeone, associate professor of psychiatry and neurobiology, Yale University
Reyes was part of a team that gave mice a high-fat diet from the time they were weaned until they reached 20 weeks, so they gained significant amounts of weight and became obese. Then the researchers looked at the brain's pleasure centers — areas known to change in drug addiction.

"What we found is that in animals that were obese, there were really dramatic changes in these areas of the brain that participate in telling us how rewarding food is," Reyes says. The changes made these areas less responsive to fatty foods, so an obese mouse would have to eat more fat than a typical mouse to get the same amount of pleasure, she says.

And some of the changes didn't go away, even when the mice returned to a normal diet.

"So it is similar to what happens in cases of chronic drug abuse," Reyes says. "The reward circuitry changes in a similar way, and that promotes the seeking of that drug, or in our case, in seeking palatable food."

That could help explain why obese children tend to remain that way as adults, she says.

Addictive Food?

More evidence of a link between food and drugs comes from a team that has been trying to understand how hunger can trigger an animal's craving for drugs.

"Hungry animals will take a lot of drugs," says Uri Shalev, a researcher at Concordia University in Montreal.


Protein Data Bank
Neuropeptide Y, a brain chemical, makes animals feel hungry. Research at Concordia University in Montreal is using the chemical to study the link between food and drugs in the brain.
Shalev and his colleagues studied rats that had learned to give themselves heroin by pressing a lever. When the scientists removed the heroin, the rats mostly stopped pressing the lever. But when the scientists also took away the rat's food, the lever pressing came back with a vengeance.

The rats would press the lever hundreds of times, "even though they don't get the drug anymore," Shalev says.

The team thought this behavior might involve a substance in the brain called neuropeptide Y, which makes animals feel hungry. And, sure enough, when hungry rats got a substance that blocks neuropeptide Y, they stopped pressing the lever.

Many other studies also have shown links between food and drugs.

A Swedish team found that a stomach hormone called ghrelin could make rats seek sugar the way addicts seek drugs. And a team at the University of California, Santa Barbara, found that male rats chose sugar over small amounts of cocaine, while female rats did just the opposite.

Even so, DiLeone, the Yale researcher, says it's still not clear how far the food-drug comparison holds up, especially in people.

"There's an ongoing argument in my field whether food is addictive or not," he says. "But whether it's addictive or not, there's probably components that are similar to addiction."

That means it makes sense to focus on eating behavior early in life, when the brain is adapting to a particular environment. It also probably makes sense to take approaches used to treat addiction and adapt them to overeating," DiLeone says.

The new studies on overeating and addiction were presented at the 2010 Society for Neuroscience meeting in San Diego.

I think this is happening to me.  Although I'm not trying to gain weight having so many large friends on-line is causing me to grow bigger and bigger...    and I like it.

http://www.nytimes.com/2007/07/26/health/26fat.html?_r=1

People are more likely to become obese when a friend becames obese. That increased a person’s chances of becoming obese by 57 percent. There was no effect when a neighbor gained or lost weight, however, and family members had less influence than friends.

It did not even matter if the friend was hundreds of miles away, the influence remained. And the greatest influence of all was between close mutual friends. There, if one became obese, the other had a 171 percent increased chance of becoming obese, too.

Since I replied to someone else's . . .

There is at least one person on your friends list that wants to yiff the hell out of you.

So lets play the Yiff or Pass game.

The rules are simple.

If you want to yiff the person who posts this, send him or her a reply saying "I'd yiff you." But, you have to post this in your journal, in exchange.

And marvel at the replies.