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BRAIN SEX

Scott sfelder at nortexinfo.net
Tue Sep 2 16:49:29 EST 1997


The following is a quote from the book "Brain Sex; The Real Differences
Between Men and Women" by Anne Moir phd. and David Jessel. Its copyright is
1989.
The book is written to the general population. I was wondering what you
(the professionals) thought about this book, if you read it. I was also
wondering if you knew of any books on this subject that are both more up to
date and written to the general population. If what this book has to say
(and I believe it's as closer to the truth then anything else I've read)
factual, why isn't the general population more aware of these differences
in the male and female brain. Why do the vast majority of people still
believe that these differences are socialize?

I saw a discussion on PBS television the other day. They were discussing
why girls don't do as well as boys in math. In their minds, the reason
girls do less well  was because our patriarchal society is reflected in our
school system and passively telling girls that they can't do as well as
boys; so girls don't. I wanted to ask them if this is true (that our
patriarchal schools favor boys over girls) why do boys far out number girls
in remedial reading.
Thank you 
Scott

Chapter 3 pages 44-49
"How the difference in the brain structure relates to the differences found
in behaviour and ability between the sexes is an area of intense debate
among scientists. After talking to the the world's principal specialist, we
have arrive at this picture of their current working hypothesis.
       What makes us better at one thing or another seems to be the degree
to which a particular area of the brain is specifically devoted to a
particular activity - whether it is focused or difussed. Men and women are
better at the skills that are controlled by specific areas of the brain -
but different areas of their brains are focused for different things.This
means that the male and female pattern of brain organisation has advantages
and disadvantages for both sexes. The male pattern, with more brain
functions specifically organised,  means that men are not so easily
distracted by superfluous information....
     A leading Canadian brain sex researcher, Sandra Witleson, suggest that
this difference may make it easier for men to perform two different
activities at once. She suggests, for example, that talking and map reading
can both be done at the same time much more easily by a man than a woman.
In a man each activity is controlled by different sides of the brain. In a
woman the same activities are controlled by areas on both sides of the
brain. The two activities can interfere with each other and she will not be
as good at talking and map reading at the same time.
     The differences in brain organisation, according to many research
workers, also provides an explanation for male superiority in spatial
ability. A woman's spatial skills are controlled by both sides of the
brain. There is an overlap with areas of the brain that control other
activities. The female is trying to do two things at once with the same
area of the brain and spatial abilities suffer. In a man the spatial
abilities are controlled by a more specific area of the brain, so there is
much less chance that other activities will interfere.
     There is a further difference in that women often apply verbal methods
to solve abstract maths problems. This approach will not be as effective as
the male who is using the right, visual side of the brain to solve that
type of problem. It is far quicker and easier to solve such problems with
the right-side brain skills than with the verbal left-side brain skills.
     The superiority of women in verbal tests can also be explained by the
difference in brain organisation. The language skills related to grammar,
spelling and writing are all more specifically located in the left-hand
side of the brain in a woman. In a man they are spread in the front and
back of the brain, and so he will have to work harder than a woman to
achieve these skills.

So far we have mostly discussed language and spatial  skills; but the brain
is more than a mere calculating machine. It determines our emotions, and
our capacity to respond to them and express them. Sandra Witleson has
studied how people respond to emotional information fed to the right
hemisphere and then the left hemisphere. She made use of the fact that
visual images restricted to the right-hand field of view are transmitted to
the left side of the brain, and those restricted to the left-hand field are
transmitted to the right side of the brain.
     The visual images she used were emotionally charged. She found women
recognized the emotional content whichever side of the brain the image was
transmitted to. Men only recognised the emotional content when the image
was transmitted to the right-hand side of the brain.
     Women have their emotional responses residing in both left and right
sides of the brain. In men the emotional functions are concentrated in the
right side of the brain. 
     The importance of the differences in brain organisation for emotion
becomes clearer in the light of the latest discovery of sex differences in
the brain.
     The difference relates to the corpus callosum, the bundle of fibres
that link the left and right sides of the brain. These nerve fibres allow
for the exchange of information between the two halves of the brain. In
women the corpus callosum is different from in the male brain.
     In blind tests on fourteen brains obtained after autopsy, the
scientists found that in women an important area of the corpus callosum was
thicker and more bulbous than in men. Overall, this key message-exchange
centre was bigger, in relation to overall brain weight, in women than in
men. The difference could be precisely discerned.
     The two sides of the brain, connected by the corpus callosum, have a
larger number of connections in women. This means that more information is
being exchanged between the left and right sides of the female brain.
     And the latest research has shown that the more connections people
have between the left and right hemispheres, the more articulate and fluent
they are. This finding provides a further explanation for women's verbval
dexterity. But could the corpus callosum provide the answer to another
mystery; could it provide a somewhat prosaic solution to the secret of
female intuition? Is the physical capacity of a woman to connect and relate
more piecces of information than a man explained not by witchcraft, after
all, but merely by superior switchgear? Since women are in general better
at recognising the emotional nuances in voice, gesture, and facial
expression, a whole rand of sensory information. They can deduce more from
such information because they have a greater capacity than men to integrate
and cross-relate verbal and visual information.

Some scientists suggest that the difference in emotional response in men
and women can be explained by the difference in the structure and
organisation of the brain.
     Man keeps his emotions in their place; and that place is on the right
side of his brain, while the power to express his feelings in speech lies
over on the other side. Because the two halves of the brain are connected
by a smaller number of fibres than a woman's, the flow of information
between one side of the brain and the other is more restricted. It is then
often more difficult for a man to express his emotions because the
information is flowing less easily to the verbal, left side of his brain.
     A woman may be less able to separate emotion from reason because of
the way the female brain is organised. The female brain has emotional
capacities on both sides of the brain, plus there is more information
exchanged between the two sides of the brain. The emotional side is more
integrated with the verbal side of the brain. A woman can express her
emotions in words because what she feels has been transmitted more
effectively to the verbal side of ther brain.
     The differences in brain structure, and the consequent differences in
ability, bias men and women towards dealing with problems by employing
their best attributes. Sandra Witleson calls this 'the preferred cognitive
strategy'. What it broadly means is playing to your mental strenghts.
Witleson suggests that there may be fewer female than male architects (and,
for that matter, scientists and mathematicians) because, the female spatial
sense being weaker, they tend to prefer a different 'cognitive strategy' -
to use another, stronger, part of their brain. It could also explain the
riddle of why there are so many more female musician than composers,
because they play to strengths in the female brain such as control over
fine movement of the hands and voice. Composing music demand the capacity
to see the pattern and involves abstract mathematical ability, primarily a
function of the right side of the brain. Obviously our culture and our
history has something to do with; but, clearly, so does our biology.

A picture is emerging, and it is the image of two brains, differently
organised, and differentially connected, in the male and the female of our
species. The knowledge is growing, day by day, as new papers and monographs
appear in the learned journals. This information is too important to be
left floating in academic outer space because it is about *us*. It shows
how we are different because our brains are different."
     


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