Discrepancies between men and women


There are obvious physiological brain differences and therefore psychological differences in gender – but what subtleties can be explained?

It is best to start with the question, what is a gender? Scientifically is it male and female as defined by our chromosome arrangement of X/X female and X/Y male.

However, there are exceptions to this rule – like XX male syndrome – which is where a gene or mutation (depending on severity) can cause the development of a male from a female chromosome arrangement.

90% of the time this occurs from the introduction of a single gene (SRY) from the Y chromosome that is swapped to one of the X chromosomes in the farther. So maybe we aren’t that different after all?

What are the differences between males and females?

Anatomically there are obvious contrasting features between males and females, in terms of height, reproductive organs and location of muscle mass.

The psychological differences are more complicated.

There are many mental functions and behaviors that vastly differ between sexes. But are they derived from genetics (X/X, X/Y) or from the environment? The classic nature nurture debate.

There is one known genetic process that may result in different emotions, cognitive abilities and personality.

X-inactivation only occurs in females (X/X) and is where one of the two X chromosomes is randomly inactivated.

This is an important step to ensure females don’t have too many genes switched on - an example of where too many genes are switched on is Down syndrome. In Down syndrome there is an extra chromosome present.

X-inactivation occurs to all cells in the body of a 4-week old female baby, even in the cells of the brain. Causing the differences in male and female brains to be very different in design.

Where you can observe this trait is in calico cats, female cats have speckled fur and the male cats have one solid colour of fur. This is a real representation of X-inactivation.

A more applicable example is highlighting a gene that (For example) codes for musical in the brains of males and females. A female may have a speckled pattern of this gene due to the random switching of their X chromosome. Making females have a bit of both musical and tone deaf.

Alternatively, a male (only one X-chromosome) would have the gene or not. So they would either be tone deaf or musical.








Radial mosaicism and tangential cell dispersion both contribute to mouse neocortical development - Nature, 1993. Tan & Breen.

Male and female brain slices of the same location, highlighting a gene that is of solid colour in the blue in males and stripped darker bands in females.

How does this change the psychology of different sexes? A female may be more speckled or stripped in their traits, whilst a male more solid on one or the other.


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