From Diana J. Choyce
Dec 20 - 26, 1999
Over the last millennium science has used men in their research
for more than it has used women. The last decade has seen a great increase in the
inclusion of women. One of the most sought-after questions is how do men and women think
and what are the differences? That is a debate I imagine that will go on for centuries.
But recently science has begun to look into it with a new fervour. Perhaps out of
desperation, but more likely because it's needed in testing theories and adjusting
therapies according to gender.
For decades people have believed that the larger the brain the smarter
the person. And since women have smaller brains, men must be smarter. But men and women
score equally well on intelligence tests despite the size difference. Even scientists have
thought the bigger the animal brain the smarter it was. However, a study done by the
University of Pennsylvania has found that its not the size but what's inside that counts.
They used 80 volunteers divided equally by men and women, and magnetic resonance imaging
in their project. The brain scan showed definite differences in the sizes of some key
components inside the male and female brains. The part of the brain called "gray
matter" is what allows us to think. Women typically have a 44 ounce brain but its
made up of 55 per cent gray matter. Men have 50 per cent gray matter in their 49 ounce
brain. They also found that men have more "white matter" which transfers
information between distant regions of the brain. This may help explain why women are
better at verbal tasks and men are more adept at spatial tasks which is knowing where they
are in relation to the world. This could explain their reticence in asking for directions!
Scientists at John Hopkins University have been studying the gender
differences in the part of the brain that estimates time, judges speed, sees 3-D objects,
and solves mathematical problems. The study shows that a region of the brain known as the
inferior parietal lobe (IPL) is much larger in men. The IPL allows the brain to process
information from the senses such as vision and touch, and is located in two parts on
either side of the brain. The left IPL is involved in perception such as judging speed,
estimating time, and mentally rotating 3-D images. The right IPL dictates spatial
relationships such as between body parts and awareness of one's feeling and emotions. They
are not saying that men are automatically better at things like math and physics, because
there are many exceptions to the rule. But in general there is a grain of truth to the
belief that men are better at Math and women are better in English. Another study has
suggested that these differences don't show up until after middle school ages. Also women
who normally score lower in math tests did much better when the time limit for the test
was not used. This suggests that women simply use a different process in their thinking to
solve these types of problems.
Research at the Henry Ford Health System has concluded that men have a
greater age related brain shrinkage than women. They used magnetic resonance imaging to
measure the brain size of three hundred and thirty men and women over the age of sixty
six. Brain shrinkage is measured by the amount of fluid that develops around the outside
of the brain. They found that men had far more fluid in the frontal and temporal lobes.
These lobes control thinking, planning, and memory. Shrinkage was also found at the back
of the brain in the parieto-occipital region of men. This area is responsible for thinking
as well as sensory information. So the next time your husband says he forgot to bring home
the milk, give him the benefit of the doubt!
Another study, by two doctors at the Columbia University College of
Physicians and Surgeons, has focused on matters of the heart. We have always known there
are definite differences there, but this study concerns the gender specific biology of the
structure of the heart. Up until recent years most studies have been on men, but every
year 350,000 women die of heart disease. And half a million have heart attacks every year.
This makes it the number one killer of women. The "sinus node", the heart's
natural pacemaker, marks the cadence of a normal heartbeat. When this cadence is
interrupted, it's called ventricular fibrillation. It means the heart cannot supply a
regular blood flow to the heart. If this natural rhythm is not restored quickly, death
will follow. Women have a faster resting heart rate than men. And they also have a longer
QT, or separation between beats. This makes them susceptible to arrhythmia, which is an
irregular heartbeat. Knowing this fact can help doctors find gender specific therapies and
drugs to treat heart problems in men and women.
While the monies for some of these studies would probably be better
spent on research related to diseases like HIV, they are certainly fascinating. The
differences between men and women will be debated until the end of time, but some
understanding is a positive thing. Especially if it creates more patience and caring
between the sexes. It's ok for there to be biological and physiological differences, as
long as respect and love remain equal.