O que você pede chorando que eu não faço sorrindo?

In Women’s Tears, a Chemical Cold Shower
By PAM BELLUCK NY Times
January 6, 2011
When we cry we may be doing more than expressing emotion. Our tears, according to striking new research, may be sending chemical signals that influence the behavior of other people.
The study, published on Thursday in the journal Science, could begin explain something that has baffled scientists for generations: Why do humans, unlike seemingly any other species, cry emotional tears?
In several experiments, researchers found that men who sniffed drops of women’s emotional tears became less sexually aroused than when they sniffed a neutral saline solution that had been dribbled down the women’s cheeks. While the studies were not large, the findings showed up in a variety of ways, including testosterone levels, skin responses, brain imaging and the men’s descriptions of their level of arousal.
“Chemical signaling is a form of language,” said one of the researchers, Dr. Noam Sobel, a professor of neurobiology at the Weizmann Institute in Israel. “Basically what we’ve found is the chemo-signaling word for ‘no’ — or at least ‘not now.’ ”
The researchers are now studying men’s emotional tears, so the scientific implications of, say, the weeping of John Boehner remain an open question. But Dr. Sobel said he believed men’s tears would also turn out to transmit chemical signals, perhaps serving to reduce aggression in other men.
Dr. Sobel said the researchers started with women because, when they advertised for “volunteers who can cry with ease,” they could not find men who were “good criers,” readily able to fill collection vials with sad tears. Fortunately, he said, “we have a male crier now.”
Several experts said the findings — besides potentially adding subtext to crying songs through the ages, from Roy Orbison to the Rolling Stones — could be a first step toward a potential breakthrough on a mysterious subject.
The discovery of a chemical signal in tears suggests “a novel functional role for crying,” said Martha K. McClintock, a psychology professor at the University of Chicago known for her work on pheromones and behavior. “It really broadens the possibilities of where signals are coming from.”
Robert R. Provine, a psychologist and neuroscientist at the University of Maryland, Baltimore County, who has studied crying, said the discovery was “a really big deal” because “emotional tears are a very important evolutionary development in humans as a social species” and this “may be evidence of another human pheromone.”
Why women’s tears would send a message of “not tonight, dear” is somewhat puzzling. Some experts suggested it could have evolved to reduce men’s aggression toward women weakened by emotional stress. The studies did not measure the effect on aggression, although future research might, Dr. Sobel said. Another thought, he said, is that the effect could have evolved in part to coincide with women’s menstrual cycles.
“There’s several lines of evidence that women cry much more during menstruation, and from a biological standpoint that is not a very effective time to have sex, so reducing sexual arousal in your mate at that time is really convenient,” he said.
Dr. McClintock, who reported 40 years ago that women living together tend to synchronize menstruation, objected to that theory, saying, “Oh, please — do we know that women cry more often during menstruation?”
She said it was “premature to speculate about the evolutionary function” of chemo-signaling in tears, adding: “I have no doubt that it affected sexuality as they report, but I would be very surprised if it doesn’t turn out to affect other emotions in other contexts. Maybe it’s affecting some deeper, more fundamental psychological process that drives the effect that they’re reporting.”
The researchers happened accidentally upon the evidence that women’s tears tell men to take a cold shower. They had assumed chemical signals from tears would trigger sadness or empathy in others. But initial experiments found that sniffing women’s tears did not affect men’s mood or empathy, but “had a pronounced influence on sexual arousal, a surprise,” Dr. Sobel said.
Deciding to investigate more rigorously, they assembled a “bank of criers,” Dr. Sobel said: “six women who were really good” at bawling their eyes out, plus several “backup criers.”
He said, “We had to use fresh tears,” no more than two hours old, so criers were called on frequently to sob a renewed supply. The women, roughly 30 years old, watched scenes from their favorite tear-jerkers, including “Life Is Beautiful,” “My Sister’s Keeper,” “When a Man Loves a Woman,” and an Israeli movie, “Broken Wings,” said Yaara Yeshurun, a doctoral student on the team. She was also one of the criers, losing it over “Terms of Endearment.”