Greater male than female variability in regional brain structure (Paper)
biorxiv.org
biorxiv.org
I first heard of this when researching chess. Men rank ~200 ELO points higher than women at chess, which is a fairly significant amount. Men also seem to do better at several other non-physical competitions like Go, video games, and Jeopardy. Plus, the history of math and science is dominated by men at the top.
It seems like men are not smarter on average, but they do peak higher (and valley lower).
Yeah - there are also a lot more men than women in prison.
There has been a lot of research on this topic. You can not measure the testosterone in a group and make a prediction about who is going to commit a crime. If you measure testosterone on criminals, you can't make any prediction about what kind of crime they did.
There are weak associations such as risk taking (possible facilitated through increased dopamine transmitters), but there are much stronger links between criminals. To mention a few: Social economical status, social support structure, and childhood trauma is much better predictors than high testosterone.
Hormones are a terrible explanation for crime, even if they often have a weak association. Did you know that women are much more likely to have committed a crime during pms? The crime statistics support the link, but ask a researcher and they will list multiple reason why such correlation make for very weak association rather than strong evidence of a link between hormones and crime.
Well, if the group is mixed, with both men and women, then you can predict that 95% of the violent crimes will be committed by people with higher testosterone (i.e. men). Surely in that sense it's about testosterone, not genitalia?.
That's why it's very surprising to hear that the _level_ of testosterone among men has no predictive power.
Many research papers has been written on the topic of testosterone and violence, including meta studies. The general conclusions is... there is a weak link between testosterone and violence. No cause and effect, but there is a small amplification of existing behavior, a common finding among endogenous studies.
The full reason is complex, but a simplification is that testosterone increase preexisting behavior in relation to social status hierarchy. It makes individuals spend more energy in defending their place on the ladder (spending more time looking at faces to recognize threat, increased response to threatening faces, more suspicion against ambiguous faces). This in turn has a link towards violence, but only in cultures where status is given as an reward for violence.
But there is an additional complexity that should be mentioned. A lot of the effects of hormones such as testosterone only happen as a result of changing levels of hormones rather than absolute values. The absolute value has less of a predictive effect then changes over a short time frame.
I have a couple guesses:
1. This may be a period in which men experience the greatest status uncertainty and so may resort to violence in an attempt to solidify their place in a social hierarchy.
2. This is generally the age range during which many disorders that are more prevalent or severe in men (such as schizophrenia, bi-polar, etc.) begin to manifest.
1) I have not read any study however that looked at periods of social uncertainty, but it sounds plausible.
2) My guess would go towards the relation of frontal cortex maturation. Before fully maturation, other parts of the brain "step in" and handle some of the frontal cortex' role, but by around age 25 they stop doing that.
So, do you mean that such disorders originate from the frontal cortex, and that the reason they manifest by 25 or so is because it is at that point that the frontal cortex is no longer "supported" by other parts of the brain and it's flaws become apparent? Interesting if so.
You could alternatively look at the negative manifestations of variability, like increase crime and violence, and try to socially discourage it. Expose males to "crime is bad. bad men go to prison where they cannot have sex with women for many years. if you do crime you are bad." Observe whether crime rate of men relative to women decreases. If it does not, it is evidence that social encouragement is not responsible for the difference in crime.
You could also do a control where you discouraged men from achieving. "Nerds are gross" and see if that leads to a victory for feminism.
https://en.wikipedia.org/wiki/Judit_Polg%C3%A1r
The article has some quotations about Judits opinion:
"I always say that women should have the self-confidence that they are as good as male players, but only if they are willing to work and take it seriously as much as male players."
and after a tournsment in 1988 (12yo)
"These other girls are not serious about chess...I practice five or six hours a day, but they get distracted by cooking and work around the house."
Well, no, it hasn't, because whatever the one family does can't change society at large and the messages/treatment women receive from it. The quotes you provide are examples of that.
Could this regional brain structure account for the higher variance in male intelligence?
The paper assumes a prior of males having greater variance in a diverse set of traits, and frames itself as exploring the cause of such variance.
It proceeds to empirically study brain structure, and found that "results confirmed the hypothesis of greater male variability in brain structure.".
Parent's question, while relevent, is much broader than what the paper attampted to answer. I see no discussion in the paper that would render the question moot.
Instead of asking again "maybe men just outcompete women because they have an inherent advantage", can we please just not do this. Again.
It's become really disheartening to see this question being asked, because of a long history of infantilizing women and misusing science to prove it.
Even if we're talking about population-level differences. I'm asking for empathy here, because every time a gender study comes up, it seems like someone again needs to ask if women really deserve an equal role at the table, as historical leaders or scientists, as part of humanity.
What “many traits” do you think are being referenced?
I’ve worked with many female engineers who are unquestionably smarter than I am. I’m married to one. Of course we are talking population-level differences, and I’m not suggesting that women shouldn’t be included in any table based upon meritocracy.
That doesn’t negate the fact that a president of Harvard was forced to step down for having a hypothesis that there could possibly be a gender difference explained by variance. Now that his hypothesis has a glimmer of possibly being supported by research, again, it continues to be vilified.
I’m asking for a world where a scientist can freely propose a hypothesis and not be forced to step down. Anything else is driving the anti-enlightenment.
Lawrence Summers is the Galileo of our time.
2. Proposing a hypothesis is not doing science. Science would involve actually testing a hypothesis by applying rigorous and reliable methods that suit the phenomenon being investigated, verifying the validity of results, interpreting the results and having the results reviewed by peer experts.
3. Summers’ remarks were merely pulled out of his ass and we’re in no way informed by any scientific process.
4. He has crucially undermined the work of countless women working as scientists at Harvard, and therefore failed in his duties as leader of that world class institution.
4. He resigned as a result of a no-confidence vote from the faculty (i.e. all the smart people who work at Harvard), which underscores how shitty he was at his job and how dumb his remarks were.
> Lawrence Summers is the Galileo of our time.
5. lol
Therefore they don't get any Y stuff. And a mutation in one chromosome X can be mitigated by a non-mutation in the other chromosome X.
Since bright colours, elaborate songs, and other courtship displays tend to make male birds more vulnerable to predation, I would hypothesize that male birds also have greater trait variability due to all this risk taking. It would make for an interesting study anyway.
As a layman reading the paper, my understanding is that greater male variability has already been observed in "personality, coginitive abilities, and school achievement". The question here whether and to what extent that variability is due to "early life genetic or gene-environment interaction mechanisms". The implication of this paper seems to be that since pervasive brain-structure differences in variability can be observed throughout the lifespan of individuals, the variability in high-level traits are likely to have strong genetic component.
The introduction in the paper focuses on the "downside" of high-variability in males (their propensity for neurological disorders). Unless I've missed it, any "upside" to high-variability was left unstated.
[1] https://www.discovermagazine.com/the-sciences/1-in-200-men-d...
it's nurture + nature + serious amounts of work that makes extraordinary levels of talent; you can't get away with anything less.
imho, schools and the popular culture cause brain damage, so who knows what the actual situation is.
I know the article doesn't do this specifically, but since people will and do cite results like these as prescriptive facts which guide the people are waaay too complex and adaptable for helping us guide our lives.
also interesting: explore similarities in background between structural brain outliers.
There is a strong correlation throughout human history between a discipline not being taken seriously and the same discipline growing by leaps and bounds. It is of course usually unintentionally or intentionally covered up by academics of various sorts. One major example is medicine - most of the ridiculously useful developments we got come from people experimenting and discovering without much formal constraints. Leonardo Da Vinci comes from a "guild of arts and medicine", the discovery of the nicotine patch came from the scientist almost killing himself with concentrated nicotine, incredible discoveries from WW1 till the end of WW2.
Just my 2c.
Something I've seen actually work really well for socialization is homeschooling, where children are exposed both to children of a variety of ages (younger and older) and the interactions with adults are more personable. They also more often get to see adults interacting with each other as adults.
I suspect there is probably a profound benefit to children who have adult figures in their own lives (aside from their parents) that they can look up to as a models of successful behavior - as opposed to merely having pop culture and other kids to model themselves after.
Say you have the typical dad-works-and-mom-stays-home setup. Mom's got to go to the grocery store? Kids go, too, and practice their arithmetic in real-world environments. They also interact with at least the cashier, and probably a number of other adults.
It's a nice day? They go to the park, and look at wildlife and plants. Along the way, they interact with a number of other people at the park. And so it goes. They interact with non-family-members all over the place.
But if that's not enough for socialization, well... when we got concerned about socialization, we grabbed the kids, dragged them into the bathroom, and beat them up for their lunch money. You know, so that they got socialized the way that public school kids did.
We just put ours in a drab room with an uncomfortable chair and a video of an adult droning on for several hours.
I went through public/government schools the whole way through, and my experience was fairly positive overall. However, having now met many adults who were homeschooled, and participating in the homeschool scene as a parent, I'm fairly convinced that homeschooling results in more mature, more prepared individuals.
Obviously, some kids will be overly cloistered and may be hurt socially by that, but that doesn't seem to be the norm. Besides, plenty of kids come out of government schools pretty messed up as it is.
There’s arguably a stronger trend between work that’s not taken seriously and work that is not meaningful, rigorous or grounded on solid foundations. Bad research is typically ignored because it is recognized to be poorly conceived. Most scraps left behind really are scraps.