7 ms·

Sexual dimorphism of brain structure in the 1-month infant

19 points by mkempe 9y ago

uoaei 9y ago
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.
mkempe 9y ago
"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."
mpweiher 9y ago
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.
- milankovic 9y ago
  Do you want to get burned at the stake? 'Cause that's how you get burned at the stake.
- yorwba 9y ago
  Are you alluding to "gender is a social construct"? In which case I want to point out that this paper is about sexual dimorphism and the study subjects are likely too young to have a gender yet (or any other kind of social role, really). IIRC, children tend to start to care intensively about gender-appropriateness around age 3.
- mkempe 9y ago
  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.
  - tscs37 9y ago
    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-doesnt-just-mean-schools-and-peers/ http://slatestarcodex.com/2016/03/16/non-shared-environment-... 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...
- quantumofmalice 9y ago
  Everything I Don't Like Is A Social Construct - A Sociologists Guide To Arguing On The Internet
- Yetanfou 9y ago
  Just add one line: (e) the scientific method. Then answer (e) This solves all these questions, for now and forever. Theory, proof, fact and figures pale in the shining light of emotion and feeling in this new age of irrationality.
  - candiodari 9y ago
    This is called postmodernism. If things aren't the way I like, it must be a conspiracy, if necessary by the entire world.
debacle 9y ago
Is brain hypermasulinity still a theoretical cause of autism?
faitswulff 9y ago
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.
- tscs37 9y ago
  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.
  - candiodari 9y ago
    It's also a question of inputs, practice and body structure. I'm sure ravens massively outperform even the smartest of humans on landing after a jump, and their sense of what the air pressure is around them, even including localized changes that neither us nor them can see should be impeccable, despite using less and worse sensors, and much less processing capacity to do this with. But for humans there's very rarely any reason to do it at all, and so we suck at it. So this is not any stranger than the fact that most Chinese suck at writing German poetry, and vice versa.
  - yorwba 9y ago
    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.)
    - 9y ago

19 points by mkempe 9y ago

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.

mkempe 9y ago

"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."

mpweiher 9y ago

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.

milankovic 9y ago
Do you want to get burned at the stake? 'Cause that's how you get burned at the stake.
yorwba 9y ago
Are you alluding to "gender is a social construct"? In which case I want to point out that this paper is about sexual dimorphism and the study subjects are likely too young to have a gender yet (or any other kind of social role, really). IIRC, children tend to start to care intensively about gender-appropriateness around age 3.
mkempe 9y ago
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.
- tscs37 9y ago
  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-doesnt-just-mean-schools-and-peers/ http://slatestarcodex.com/2016/03/16/non-shared-environment-... 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...
quantumofmalice 9y ago
Everything I Don't Like Is A Social Construct - A Sociologists Guide To Arguing On The Internet
Yetanfou 9y ago
Just add one line: (e) the scientific method. Then answer (e) This solves all these questions, for now and forever. Theory, proof, fact and figures pale in the shining light of emotion and feeling in this new age of irrationality.
- candiodari 9y ago
  This is called postmodernism. If things aren't the way I like, it must be a conspiracy, if necessary by the entire world.

debacle 9y ago

Is brain hypermasulinity still a theoretical cause of autism?

faitswulff 9y ago

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.

tscs37 9y ago
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.
- candiodari 9y ago
  It's also a question of inputs, practice and body structure. I'm sure ravens massively outperform even the smartest of humans on landing after a jump, and their sense of what the air pressure is around them, even including localized changes that neither us nor them can see should be impeccable, despite using less and worse sensors, and much less processing capacity to do this with. But for humans there's very rarely any reason to do it at all, and so we suck at it. So this is not any stranger than the fact that most Chinese suck at writing German poetry, and vice versa.
- yorwba 9y ago
  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.)
  - 9y ago