All in the Head

Research probes sex-based brain differences
Story by: CTVNews.com

There are major differences in the way men and women think, as any married couple will tell you. The question is why, and where do these divergent processes come from?

New research suggests many of the clues lie deep in the brain, in subtle but pervasive differences in the way men's and women's brains are structured.

Sandra Witelson, McMaster University

Twenty-five years ago Dr. Sandra Witelson of McMaster University began studying sex-based differences in the brain. Then it was unfashionable -- now it's hot science.

"We called the brain a sex organ, which was not a frequently-used phrase at the time, and that's essentially what we're finding," she said.

Witelson's latest research shows that women have more densely-packed cells in the frontal lobe, the region responsible for judgement, personality and reasoning.

Women are also better at detecting emotions on faces, and researchers in Philadelphia are trying to find out why. They designed a study where men and women looked at faces on a screen, and then had to say how the person was feeling.

"Our main finding from this study in men and women so far is that it's a lot less work for women," said Professor Ruben Gurs with the University of Pennsylvania. "It's not such a big deal for them to tell how a person is feeling, whereas the male brains are sweating a lot more in trying to figure it out."

Women are better than men at detecting emotions on faces,

A man's brain is filled with more fluid and fat ... and that seems to speed communication throughout the brain. Women's brains meanwhile, have larger structures that control aggression.

The regions in men's brains that deal with emotion and physical action are closely packed, while women's emotional regions are more closely connected to the parts of the brain that deal with language.

"That part of the emotional brain is so close to the language part of the brain, they (women) have an easier time talking about what they feel," said Gurs. "Most men if you ask them to talk about their feelings they will say, what is there to talk about?"

Studying the differences in men's and women's brains can aid in treating aging brain diseases such as stroke or Alzheimer's

There are however dangers in interpreting the burgeoning science of brain sex.

"First of all we should not make the leap that one is better than the other," said Witelson.

Instead, she says it is important to understand the differences, and to celebrate them.

The reason for this research is partly curiosity and partly a search for understanding of brain diseases, like Alzheimer's and stroke. When the brain gets injured or sick, men and women react differently. Women recover much faster from difficulties brought on by a stroke, for example.

"If we can understand how healthy brains work and how they differ between the genders we can understand why those differences occur when brains get sick," said Witelson.