The research, which involved imaging the brains of
nearly 1,000 adolescents, found that male brains had more connections within
hemispheres, whereas female brains were more connected between hemispheres. The
results, which apply to the population as a whole and not individuals, suggest
that male brains may be optimized for motor skills, and female brains may be
optimized for combining analytical and intuitive thinking.
"On average, men connect front to back [parts of
the brain] more strongly than women," whereas "women have stronger
connections left to right," said study leader Ragini Verma, an associate
professor of radiology at the University of Pennsylvania medical school. But
Verma cautioned against making sweeping generalizations about men and women
based on the results.
Previous studies have found behavioral differences
between men and women. For example, women may have better verbal memory and
social cognition, whereas men may have better motor and spatial skills, on
average. Brain imaging studies have shown that women have a higher percentage
of gray matter, the computational tissue of the brain, while men have a higher
percentage of white matter, the connective cables of the brain. But few studies
have shown that men's and women's brains are connected differently.
In the study, researchers scanned the brains of 949
young people ages 8 to 22 (428 males and 521 females), using a form of magnetic
resonance imaging (MRI) known as diffusion tensor imaging, which maps the
diffusion of water molecules within brain tissue. The researchers analyzed the
participants as a single group, and as three separate groups split up by age.
As a whole, the young men had stronger connections
within cerebral hemispheres while the young women had stronger connections
between hemispheres, the study, detailed today (Dec. 2) in the journal
Proceedings of the National Academy of Sciences, found. However, the
cerebellum, a part of the brain below the cerebrum that plays a role in
coordinating muscle movement, showed the opposite pattern, with males having
stronger connections between hemispheres.
Roughly speaking, the back of the brain handles
perception and the front of the brain handles action; the left hemisphere of
the brain is the seat of logical thinking, while the right side of the brain
begets intuitive thinking. The findings lend support to the view that males may
excel at motor skills, while women may be better at integrating analysis and
intuitive thinking.
"It is fascinating that we can see some of
functional differences in men and women structurally," Verma told
LiveScience. However, the results do not apply to individual men and women, she
said. "Every individual could have part of both men and women in
them," she said, referring to the connectivity patterns her team observed
When the researchers compared the young people by age
group, they saw the most pronounced brain differences among adolescents (13.4
to 17 years old), suggesting the sexes begin to diverge in the teen years. Males
and females showed the greatest differences in inter-hemisphere brain
connectivity during this time, with females having more connections between
hemispheres primarily in the frontal lobe. These differences got smaller with
age, with older females showing more widely distributed connections throughout
the brain rather than just in the frontal lobe.
Currently, scientists can't quantify how much an
individual has male- or female-like patterns of brain connectivity. Another
lingering question is whether the structural differences result in differences
in brain function, or whether differences in function result in structural
changes.
The findings could also help scientists understand why
certain diseases, such as autism, are more prevalent in males, Verma said. By Tanya Lewis
Culled from: yahoo-news
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