15 ms·

Sex differences in functional connectivity during fetal brain development

86 points by dschuetz 8y ago

stared 8y ago
Compare and contrast with "Neurosexism: the myth that men and women have different brains" (https://www.nature.com/articles/d41586-019-00677-x https://www.nature.com/articles/d41586-019-00677-x, discussed here: https://news.ycombinator.com/item?id=19316221 https://news.ycombinator.com/item?id=19316221). Not to deny that gendered socialization makes differences (it does, as any activity). Still, I am puzzled by the dogmatic "there is no nature, there is only nurture; and don't dare to ask questions!" (maintained by some, including people I know personally). Vide - https://quillette.com/2019/03/11/science-denial-wont-end-sexism/ https://quillette.com/2019/03/11/science-denial-wont-end-sex... (discussed here: https://news.ycombinator.com/item?id=19360744 https://news.ycombinator.com/item?id=19360744) "Not a week goes by without yet another research study, popular science book, or mainstream news article promoting the idea that (a) any differences between men and women in the brain are purely socially constructed and (b) these differences have been exaggerated beyond any meaningful relevance. More recently, this argument has evolved to contend that (c) there are, in fact, no brain differences between the sexes at all. Eliot’s article appears to subscribe to a hodgepodge of all three perspectives, which not only contradict one another but are also factually incorrect." - https://slatestarcodex.com/2017/10/23/kolmogorov-complicity-and-the-parable-of-lightning/ https://slatestarcodex.com/2017/10/23/kolmogorov-complicity-... (discussed here: https://news.ycombinator.com/item?id=15539675 https://news.ycombinator.com/item?id=15539675) "Did Giordano Bruno die for his astronomical discoveries or his atheism? False dichotomy: you can’t have a mind that questions the stars but never thinks to question the Bible. The best you can do is have a Bruno who questions both, but is savvy enough to know which questions he can get away with saying out loud. And the real Bruno wasn’t that savvy." And pretty much as a side note, while some social differences ARE due to sexism, some others are because of more gender equality (and people being able to choose what they prefer, regardless of their gender): "As women have more equal opportunity, the more their preferences differ from men" http://science.sciencemag.org/content/362/6412/eaas9899 http://science.sciencemag.org/content/362/6412/eaas9899 (discussed here: https://news.ycombinator.com/item?id=18379943 https://news.ycombinator.com/item?id=18379943)
- DC-3 8y ago
  > there is no nature, there is only nurture; and don't dare to ask questions The entire post-modern left worldview is deeply rooted in the blank-state hypothesis. Very few people - across all political and academic spectra - have the scientific discipline to react rationally to criticism of the scaffolding supporting the lens through which they view the world.
  - alexpetralia 8y ago
    Would you have any reading you could suggest on this? A lot of my thinking is informed by postmodernism (mostly from that essay by Larry Wall, the original author of Perl), but I realize it's such a broad term that there may be a lot of other ideas (especially ones I disagree with, like the blank-state hypothesis) tucked in there as well.
    - DC-3 8y ago
      I'm sorry, I wouldn't be able to provide any specific reading on this. My comment above was rooted in two things. Firstly, my own observations from several years immersed in the massive internet culture war between left and right that seems to define and frame the politics of our time. Secondly, my understanding of postmodern thought which I have gained through university tuition. As such, my thoughts on these topics tend to be based in intuition not rigor, which is perhaps ironic (or even hypocritical) given that it is postmodernism which I am criticizing, but I feel that my point stands nonetheless.
      - alexpetralia 8y ago
        Haha fair enough. Well I am always open to more perspectives on it - even intuitive ones - so thanks for that.
  - cooooooffffeeee 8y ago
    This is pseudo-academic posturing nonsense. The issue people take is attributing value to the differences between sexes, not the biological differences in themselves.
fromthestart 8y ago
What do people do when confronted with research that challenges the very fabric of modern gender politics? As more research like this gets out, indicating that males and females really are genetically predisposed to different psychology, what happens to a sizable chunk of leftist politics, which currently allege men and women are identical and that differences in equity are entirely cultural and sexist in nature? What does this say of modern cultural hiring and university admittance policies that are driven by untested assumptions contradicting research like this? Perhaps our past measures of merit have not been so skewed as some people with an axe to grind would have you believe.
- camdenlock 8y ago
  Panic. The tools used to confront such inconvenient truths are, as always, censorship and bullying.
  - vorticalbox 8y ago
    Agreed, most people when faced with an valid point that disagrees with their argue end up being labelled sexist, bigoted and racist because they have nothing else to use
  - cooooooffffeeee 8y ago
    Protest isn't censorship
pmarreck 8y ago
Can someone (likely younger than me) explain to me why the concept of gender-associated cognitive differences has become so controversial, and why the “blank slate hypothesis” is the only one considered acceptable? This was an entirely different story when I was in college. 90% of all nurses are women, does that mean that 100% of the difference (from the 50/50 ideal-world gendersplit assumption) are men purely socialized not to do that? I have no interest in sports, yet 90+% of men seem to, but I kinda get it, it makes sense to me that most men would be into that. And then we get to programming, and raw interest in mechanisms... and possible correlations to gender with that, and all hell breaks loose. Have all the “monkeys prefer gender-stereotypical human toys” studies been discredited? You can’t IMHO use the socialization argument there: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2583786/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2583786/ Happy to hear anyone out on this though.
- gotocake 8y ago
  There are two main reasons I’m aware of. First, a certain kind of person tries to make a deeply sexist argument and reaches for “science” to back it up. The overall experience with that kind of thing is profoundly negative, and it has a pretty grim history, so there are strong reactions to it. It’s true that well-intentioned people do ask uncomfortable questions, but especially online they’re dwarfed by trolls and people arguing in bad faith. All told this isn’t an insurmountable problem, and more and better research can help to shine some light on the issue. It’s also not impossible to determine whether or not someone is pushing a predetermined agenda and using a given study (while ignoring others) as a bludgeon. The second, radioactive topic centers around trans people. I’m not going to touch that topic with a 10 foot pole, because online the discussion rarely develops more nuance than mysticism dressed up as science on one side, and bigotry dressed up as “common sense” arguments on the other. All told it makes for a difficult topic to discuss in good faith, absent agendas on or offline, but online it’s pure poison.
  - thisone 8y ago
    Arguments also tend to start (unstatedly) from the baseline that "male is the default and most valuable" which will get backs up.
mhermher 8y ago
I worked in an MRI lab (academic) for a few years (as a tech/programmer/statistician) and honestly these kind of sex difference findings were really common. We never did fetal scans, but we were also studying resting state fMRIs connectivity in adults. I'm semi ashamed to admit it, but a lot of times, if your main hypothesis didn't come to fruition in the data, you could usually just fall back on some sex-difference finding. You wouldn't even need to fish very hard for it. There is probably no other single 2-way split you could make that would more reliable give you large magnitude differences. I don't know how else to present that idea though. It's not completely unreasonable that there might be some inherent bias in the processing. There are really a handful of tools that everyone uses. It's possible that there is some undiscovered bias somewhere. But if that is not the case, then I am pretty convinced from my time there that the differences are real, and they are usually of large magnitude. At least larger than the more interesting findings researchers look for. Pretty crazy that they did fetal scans though. We had a lot of trouble normalizing even toddler brains on one study. I can't even imagine fetal ones.
stcredzero 8y ago
First and last phrases from the Abstract: Sex-related differences in brain and behavior are apparent across the life course...These observations confirm that sexual dimorphism in functional brain systems emerges during human gestation.
danharaj 8y ago
ITT: People discussing how difficult it is to discuss this article without vicious pomo leftists censoring them. Not ITT: The logical bridge for the conceptual chasm between observing sex differences in the brain and an explanation of how these differences in the sexes somehow always end up causing women to be in an economically and politically disadvantaged position subordinated to men.
- cooooooffffeeee 8y ago
  Oh look, someone meta complaining about gender studies who actually doesn't have anything of value to contribute. This never happens and is always productive.
  - dang 8y ago
    Could you please review and follow the site guidelines so we don't have to ban you again? In particular, please don't post flamebait or unsubstantive comments. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html You might also find these links helpful for getting the spirit of this site: https://news.ycombinator.com/newswelcome.html https://news.ycombinator.com/newswelcome.html https://news.ycombinator.com/hackernews.html https://news.ycombinator.com/hackernews.html http://www.paulgraham.com/trolls.html http://www.paulgraham.com/trolls.html http://www.paulgraham.com/hackernews.html http://www.paulgraham.com/hackernews.html
    - deleted 8y ago
      [deleted]
    - cooooooffffeeee 8y ago
      Sorry, can you just delete my account or ban it or whatever? I'm too tired.
Symmetry 8y ago
I wonder if the sex correlation would go away if they controlled for digit ratios? https://en.wikipedia.org/wiki/Digit_ratio https://en.wikipedia.org/wiki/Digit_ratio When I started reading that they talked about sex hormones differentiating at 8 weeks and I was thinking that we'd have to throw out a lot of things we thought we knew about sexual development if they'd actually seen differences before that but, no, it was was later that this was measured. It would be nice to have some notion of the effect size. That is, what fraction of female infants would have more FC-GA connection than the typical male. I'd bet that the dimorphism here is smaller than, say, height dimorphism but I wouldn't try guessing by how much.
fwip 8y ago
As is nearly always the case with sex differences in brain tissue, the variation between sexes is swamped by the variation within either sex. Here are some figures from this paper that illustrate what I mean: https://ars.els-cdn.com/content/image/1-s2.0-S1878929318301245-mmc4_lrg.jpg https://ars.els-cdn.com/content/image/1-s2.0-S18789293183012... https://ars.els-cdn.com/content/image/1-s2.0-S1878929318301245-mmc5_lrg.jpg https://ars.els-cdn.com/content/image/1-s2.0-S18789293183012... This is not intended to disparage their work. Rather, I mean to clarify that sex is not particularly predictive of what is being measured, and differences only appear when observed in aggregate.
- insickness 8y ago
  This is like saying that the variation in height between women is much greater than the variation in difference between men and women. The outcome is still the same: The average man is taller than the average woman. When the variation is cognitive, it will produce very real world statistical differences between men and women. You can't pick a random woman and a random man and assume the woman is inclined toward X and the man isn't. The statistical difference is too small to predict that. But take a thousand men and a thousand women and the percentages will bear out the small statistical difference.
  - fwip 8y ago
    "Brains appear different in an MRI" is several steps removed from behavioral differences. Height is 0 steps removed from height.
berry_sortoro 8y ago
All lies, science is fake and we MUST reject it. Men and Women are the exact same, its all a social construct!

86 points by dschuetz 8y ago

Compare and contrast with "Neurosexism: the myth that men and women have different brains" (https://www.nature.com/articles/d41586-019-00677-x https://www.nature.com/articles/d41586-019-00677-x, discussed here: https://news.ycombinator.com/item?id=19316221 https://news.ycombinator.com/item?id=19316221). Not to deny that gendered socialization makes differences (it does, as any activity). Still, I am puzzled by the dogmatic "there is no nature, there is only nurture; and don't dare to ask questions!" (maintained by some, including people I know personally). Vide - https://quillette.com/2019/03/11/science-denial-wont-end-sexism/ https://quillette.com/2019/03/11/science-denial-wont-end-sex... (discussed here: https://news.ycombinator.com/item?id=19360744 https://news.ycombinator.com/item?id=19360744) "Not a week goes by without yet another research study, popular science book, or mainstream news article promoting the idea that (a) any differences between men and women in the brain are purely socially constructed and (b) these differences have been exaggerated beyond any meaningful relevance. More recently, this argument has evolved to contend that (c) there are, in fact, no brain differences between the sexes at all. Eliot’s article appears to subscribe to a hodgepodge of all three perspectives, which not only contradict one another but are also factually incorrect." - https://slatestarcodex.com/2017/10/23/kolmogorov-complicity-and-the-parable-of-lightning/ https://slatestarcodex.com/2017/10/23/kolmogorov-complicity-... (discussed here: https://news.ycombinator.com/item?id=15539675 https://news.ycombinator.com/item?id=15539675) "Did Giordano Bruno die for his astronomical discoveries or his atheism? False dichotomy: you can’t have a mind that questions the stars but never thinks to question the Bible. The best you can do is have a Bruno who questions both, but is savvy enough to know which questions he can get away with saying out loud. And the real Bruno wasn’t that savvy." And pretty much as a side note, while some social differences ARE due to sexism, some others are because of more gender equality (and people being able to choose what they prefer, regardless of their gender): "As women have more equal opportunity, the more their preferences differ from men" http://science.sciencemag.org/content/362/6412/eaas9899 http://science.sciencemag.org/content/362/6412/eaas9899 (discussed here: https://news.ycombinator.com/item?id=18379943 https://news.ycombinator.com/item?id=18379943)

DC-3 8y ago
> there is no nature, there is only nurture; and don't dare to ask questions The entire post-modern left worldview is deeply rooted in the blank-state hypothesis. Very few people - across all political and academic spectra - have the scientific discipline to react rationally to criticism of the scaffolding supporting the lens through which they view the world.
- alexpetralia 8y ago
  Would you have any reading you could suggest on this? A lot of my thinking is informed by postmodernism (mostly from that essay by Larry Wall, the original author of Perl), but I realize it's such a broad term that there may be a lot of other ideas (especially ones I disagree with, like the blank-state hypothesis) tucked in there as well.
  - DC-3 8y ago
    I'm sorry, I wouldn't be able to provide any specific reading on this. My comment above was rooted in two things. Firstly, my own observations from several years immersed in the massive internet culture war between left and right that seems to define and frame the politics of our time. Secondly, my understanding of postmodern thought which I have gained through university tuition. As such, my thoughts on these topics tend to be based in intuition not rigor, which is perhaps ironic (or even hypocritical) given that it is postmodernism which I am criticizing, but I feel that my point stands nonetheless.
    - alexpetralia 8y ago
      Haha fair enough. Well I am always open to more perspectives on it - even intuitive ones - so thanks for that.
- cooooooffffeeee 8y ago
  This is pseudo-academic posturing nonsense. The issue people take is attributing value to the differences between sexes, not the biological differences in themselves.

fromthestart 8y ago

What do people do when confronted with research that challenges the very fabric of modern gender politics? As more research like this gets out, indicating that males and females really are genetically predisposed to different psychology, what happens to a sizable chunk of leftist politics, which currently allege men and women are identical and that differences in equity are entirely cultural and sexist in nature? What does this say of modern cultural hiring and university admittance policies that are driven by untested assumptions contradicting research like this? Perhaps our past measures of merit have not been so skewed as some people with an axe to grind would have you believe.

camdenlock 8y ago
Panic. The tools used to confront such inconvenient truths are, as always, censorship and bullying.
- vorticalbox 8y ago
  Agreed, most people when faced with an valid point that disagrees with their argue end up being labelled sexist, bigoted and racist because they have nothing else to use
- cooooooffffeeee 8y ago
  Protest isn't censorship

pmarreck 8y ago

Can someone (likely younger than me) explain to me why the concept of gender-associated cognitive differences has become so controversial, and why the “blank slate hypothesis” is the only one considered acceptable? This was an entirely different story when I was in college. 90% of all nurses are women, does that mean that 100% of the difference (from the 50/50 ideal-world gendersplit assumption) are men purely socialized not to do that? I have no interest in sports, yet 90+% of men seem to, but I kinda get it, it makes sense to me that most men would be into that. And then we get to programming, and raw interest in mechanisms... and possible correlations to gender with that, and all hell breaks loose. Have all the “monkeys prefer gender-stereotypical human toys” studies been discredited? You can’t IMHO use the socialization argument there: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2583786/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2583786/ Happy to hear anyone out on this though.

gotocake 8y ago
There are two main reasons I’m aware of. First, a certain kind of person tries to make a deeply sexist argument and reaches for “science” to back it up. The overall experience with that kind of thing is profoundly negative, and it has a pretty grim history, so there are strong reactions to it. It’s true that well-intentioned people do ask uncomfortable questions, but especially online they’re dwarfed by trolls and people arguing in bad faith. All told this isn’t an insurmountable problem, and more and better research can help to shine some light on the issue. It’s also not impossible to determine whether or not someone is pushing a predetermined agenda and using a given study (while ignoring others) as a bludgeon. The second, radioactive topic centers around trans people. I’m not going to touch that topic with a 10 foot pole, because online the discussion rarely develops more nuance than mysticism dressed up as science on one side, and bigotry dressed up as “common sense” arguments on the other. All told it makes for a difficult topic to discuss in good faith, absent agendas on or offline, but online it’s pure poison.
- thisone 8y ago
  Arguments also tend to start (unstatedly) from the baseline that "male is the default and most valuable" which will get backs up.

mhermher 8y ago

I worked in an MRI lab (academic) for a few years (as a tech/programmer/statistician) and honestly these kind of sex difference findings were really common. We never did fetal scans, but we were also studying resting state fMRIs connectivity in adults. I'm semi ashamed to admit it, but a lot of times, if your main hypothesis didn't come to fruition in the data, you could usually just fall back on some sex-difference finding. You wouldn't even need to fish very hard for it. There is probably no other single 2-way split you could make that would more reliable give you large magnitude differences. I don't know how else to present that idea though. It's not completely unreasonable that there might be some inherent bias in the processing. There are really a handful of tools that everyone uses. It's possible that there is some undiscovered bias somewhere. But if that is not the case, then I am pretty convinced from my time there that the differences are real, and they are usually of large magnitude. At least larger than the more interesting findings researchers look for. Pretty crazy that they did fetal scans though. We had a lot of trouble normalizing even toddler brains on one study. I can't even imagine fetal ones.

stcredzero 8y ago

First and last phrases from the Abstract: Sex-related differences in brain and behavior are apparent across the life course...These observations confirm that sexual dimorphism in functional brain systems emerges during human gestation.

danharaj 8y ago

ITT: People discussing how difficult it is to discuss this article without vicious pomo leftists censoring them. Not ITT: The logical bridge for the conceptual chasm between observing sex differences in the brain and an explanation of how these differences in the sexes somehow always end up causing women to be in an economically and politically disadvantaged position subordinated to men.

cooooooffffeeee 8y ago
Oh look, someone meta complaining about gender studies who actually doesn't have anything of value to contribute. This never happens and is always productive.
- dang 8y ago
  Could you please review and follow the site guidelines so we don't have to ban you again? In particular, please don't post flamebait or unsubstantive comments. https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html You might also find these links helpful for getting the spirit of this site: https://news.ycombinator.com/newswelcome.html https://news.ycombinator.com/newswelcome.html https://news.ycombinator.com/hackernews.html https://news.ycombinator.com/hackernews.html http://www.paulgraham.com/trolls.html http://www.paulgraham.com/trolls.html http://www.paulgraham.com/hackernews.html http://www.paulgraham.com/hackernews.html
  - deleted 8y ago
    [deleted]
  - cooooooffffeeee 8y ago
    Sorry, can you just delete my account or ban it or whatever? I'm too tired.

Symmetry 8y ago

I wonder if the sex correlation would go away if they controlled for digit ratios? https://en.wikipedia.org/wiki/Digit_ratio https://en.wikipedia.org/wiki/Digit_ratio When I started reading that they talked about sex hormones differentiating at 8 weeks and I was thinking that we'd have to throw out a lot of things we thought we knew about sexual development if they'd actually seen differences before that but, no, it was was later that this was measured. It would be nice to have some notion of the effect size. That is, what fraction of female infants would have more FC-GA connection than the typical male. I'd bet that the dimorphism here is smaller than, say, height dimorphism but I wouldn't try guessing by how much.

fwip 8y ago

As is nearly always the case with sex differences in brain tissue, the variation between sexes is swamped by the variation within either sex. Here are some figures from this paper that illustrate what I mean: https://ars.els-cdn.com/content/image/1-s2.0-S1878929318301245-mmc4_lrg.jpg https://ars.els-cdn.com/content/image/1-s2.0-S18789293183012... https://ars.els-cdn.com/content/image/1-s2.0-S1878929318301245-mmc5_lrg.jpg https://ars.els-cdn.com/content/image/1-s2.0-S18789293183012... This is not intended to disparage their work. Rather, I mean to clarify that sex is not particularly predictive of what is being measured, and differences only appear when observed in aggregate.

insickness 8y ago
This is like saying that the variation in height between women is much greater than the variation in difference between men and women. The outcome is still the same: The average man is taller than the average woman. When the variation is cognitive, it will produce very real world statistical differences between men and women. You can't pick a random woman and a random man and assume the woman is inclined toward X and the man isn't. The statistical difference is too small to predict that. But take a thousand men and a thousand women and the percentages will bear out the small statistical difference.
- fwip 8y ago
  "Brains appear different in an MRI" is several steps removed from behavioral differences. Height is 0 steps removed from height.

berry_sortoro 8y ago

All lies, science is fake and we MUST reject it. Men and Women are the exact same, its all a social construct!