In his piece on autism, Tim makes an interesting assertion.
As part of some paid work I do elsewhere I’ve had to read quite a bit of Simon Baron-Cohen’s work on the subject. His thesis is that autism is an extreme form of the "male type" brain. As men are more likely to be systemizers than women (and women more empathic than men), then, something like autism or Asperger’s, where people are excessively interested in systems and almost unaware that empathy itself even exists, well, an interesting thought, eh, that this group of diseases (? diagnoses perhaps) is simply an expression of an extreme form of this.
Over at Harry's Place, the Frank Ellis debate has reached fever pitch, with some claiming that brain formation is unlinked to race or sex genetics, i.e. that the brain is controlled by the same sorts of genes as ensure that (most) humans have two arms, two legs, etc. and not by the genes that control the colour of your hair, etc. In other words, that the human brain is invariable in the same way that the number of limbs is and that the only factor in cognitive function is the enviroment, or "nurture" as some call it. This is, of course, a load of horseshit.
Still, if this were the case, what Tim has just said about there being male and female brain types is no less contentious. For, if you accept that males and females can have different general brain function, then surely the same could be argued for any other broad grouping, i.e. a racial basis.
The genetic explanation rather falls down in the face of one mooted reason for the formation of what Baron-Cohen calls the "male"and "female" type brains (and men and women can have either) which is exposure to foetal testosterone. Or should that read exposure to testosterone while a foetus?
Both male and females release testosterone although in males, obviously, the quantity is greater once maturity is reached. The actual difference is that of cell receptors for testosterone; males have them, females do not. In other words, whilst females have testosterone in their bloodstream, their cells do not have the receptors to bind to the testosterone and it has no effect on their bodies (unless, of course, they are a rare XXY mutant).
So, differences in brain functionality between men and women: who'da thunk it? Lordy, is that a crowd of villagers with burning torches and pitchforks heading for Portugal...?