
Sexual dimorphism of brain structure in the 1-month infant - mkempe
https://link.springer.com/article/10.1007/s00429-017-1600-2
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mkempe
"Similar to volumetric comparisons during infancy and adolescence, after
correcting for total brain volume, males had approximately 8.4% more white
matter volume compared to females. Subcortical brain region volumes also
differed between males and females."

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mpweiher
So the only question that remains is which is the social construct:

(a) MRIs

(b) subcortical gray and white matter

(c) the notion of "volume"

(d) 1 month old infants

Or maybe (e) All of the above.

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mkempe
You forgot:

(x) assigning infants to the female vs male groups

(y) distinguishing brain matter by color

More seriously, I've always subscribed to the idea that nurture had a somewhat
greater hand than nature in gender differences, e.g. when an adult keeps
talking over my 3y-old daughter saying "you're so cute" and not listening to
what she is trying to say; or complimenting her on her hair or clothing, never
on the quality of her speech or actions.

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tscs37
I believe several studies have bounded the lower limit of nature vs nurture at
about 50% nature, though studies have gone as low at 40% and as high as 80%.

[http://slatestarcodex.com/2016/03/16/non-shared-
environment-...](http://slatestarcodex.com/2016/03/16/non-shared-environment-
doesnt-just-mean-schools-and-peers/)

I strongly believe that the fundamentals of our personality and human nature
are hardcoded and we only really fill in the details when we grow up or put
them into context of something else...

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uoaei
Disappointed to see HN still ignoring the fact that sex and gender are two
different things. No matter how correlated, the coefficient is still less than
one.

Sex is a biological expression (and exists on a spectrum with the vast
majority of the population at one of two poles) and gender is a social
construct, i.e., anyone can decide what their gender is and they have the
inalienable right, by the same liberty that we all enjoy, to do so.

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faitswulff
Reminder that Sperm whales have 18 lb brains (humans: 3 lbs) and Ravens and
crows outperform chimps on certain cognitive tasks with much smaller brains.

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tscs37
The size of a brain usually doesn't mean much, it sets a baseline, somewhat,
but the overall structure is much more important compared to
volume/size/weight. A difference in brain volume of humans doesn't necessarily
imply a huge difference in performance, just that the structure is different.
Of course a difference in performance can still occur depending on the
differences in the structure.

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yorwba
The only cognitive task that I'm aware of where there is a difference in
performance is mental rotation:
[https://en.wikipedia.org/wiki/Mental_rotation#Gender](https://en.wikipedia.org/wiki/Mental_rotation#Gender)

And this difference can be corrected by training. There should probably be a
voluntary course in mental rotation for fields where spatial awareness is
important (e.g. mechanical engineering). And I want to stress that
recommendation for such a course should be based strictly on current ability,
not gender. (I mention this because many projects of that kind only aim to
decrease differences between recognized categories, instead of simply helping
people who need it.)

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candiodari
> for such a course should be based strictly on current ability, not gender

But many times it's been shown that people get really upset explicitly BECAUSE
this is done. Why ? Because basing it on current ability will of course result
in a rather pronounced and visible gender imbalance in the actual class.

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yorwba
Well, the alternatives are to make it compulsory and waste the time of
everyone who is already good at mental rotation, or to focus on only one
gender, which will likely upset the same amount of people (although different
ones I guess) without optimally addressing the actual problem, which is that
some people are worse at mental rotation than others (some of which are male
and won't benefit from a gender-segregated class).

~~~
candiodari
So politicians have a choice:

1) waste everyone's time and don't solve the problem (but appear to) but not
be personally subject to criticism of sexism

2) actually solve the problem but open yourself up to criticism that you're
"racist" (sexist really)

We all know how this is going to go, don't we ?

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debacle
Is brain hypermasulinity still a theoretical cause of autism?

