Sunday, June 12, 2011

brains



Affecting up to 80 percent of women, PMS is a familiar scapegoat. But women are affected by their cycles every day of the month. Hormone levels are constantly changing in a woman’s brain and body, changing her outlook, energy and sensitivity along with them.
About 10 days after the onset of menstruation, right before ovulation, women often feel sassier, Brizendine told LiveScience. Unconsciously, they dress sexier as surges in estrogen and testosterone prompt them to look for sexual opportunities during this particularly fertile period.
A week later, there is a rise in progesterone, the hormone that mimics valium, making women “feel like cuddling up with a hot cup of tea and a good book,” Brizendine said. The following week, progesterone withdrawal can make women weepy and easily irritated. “We call it crying over dog commercials crying,” Brizendine said.
For most women, their mood reaches its worst 12-24 hours before their period starts. (…)
Over the course of evolution, women may have been selected for their ability to keep young preverbal humans alive, which involves deducing what an infant or child needs — warmth, food, discipline — without it being directly communicated. This is one explanation for why women consistently score higher than men on tests that require reading nonverbal cues. Women not only better remember the physical appearances of others but also more correctly identify the unspoken messages conveyed in facial expressions, postures and tones of voice, studies show. (…)
Brain-imaging studies over the last 10 years have shown that male and female brains respond differently to pain and fear. And, women’s brains may be the more sensitive of the two. (…)
“A women’s sex drive is much more easily upset than a guy’s,” Brizendine said.
For women to get in the mood, and especially to have an orgasm, certain areas of her brain have to shut off. And any number of things can turn them back on.
A woman may refuse a man’s advances because she is angry, feeling distrustful — or even, because her feet are chilly, studies show.