August 8, 2005

Extreme male brain.

Look out! The scientists are categorizing brains:
Three types of people were revealed through our study: one for whom empathy is stronger than systemizing (Type E brains); another for whom systemizing is stronger than empathy (Type S brains); and a third for whom empathy and systemizing are equally strong (Type B brains). As one might predict, more women (44 percent) have Type E brains than men (17 percent), while more men have Type S brains (54 percent) than women (17 percent).
As you may have noticed, scientific findings that put women in a bad light are frowned upon, but don't worry. The NYT op-ed I've just quoted goes on to say this:
According to what I have called the "extreme male brain" theory of autism, people with autism simply match an extreme of the male profile, with a particularly intense drive to systemize and an unusually low drive to empathize. When adults with Asperger's syndrome (a subgroup on the autistic spectrum) took the same questionnaires we gave to non-autistic adults, they exhibited extreme Type S brains. Psychological tests reveal a similar pattern.

And this analysis makes sense. It helps explain the social disability in autism, because empathy difficulties make it harder to make and maintain relationships with others. It also explains the "islets of ability" that people with autism display in subjects like math or music or drawing - all skills that benefit from systemizing.
The author of this piece, Simon Baron-Cohen, posits that the increase in autism is "the genetic result of 'assortative mating,'" as two strong systematizers have children together. He doesn't go on to say it, but it seems necessary, if this is to be the theory, to have an idea why more strong systematizers are mating these days.

It's outrageously politically incorrect to go where that theory seems to be headed and say that the women's movement is to blame for autism. More women in the workplace means that more men meet and bond with women who share whatever brain type they have. It thus becomes more likely that two extreme brain types will have children together. In the pre-feminist set-up, men would be more likely to mate with women who would nuture and care for them. Her empathizing brain type would moderate his and save their children from autism. But in the modern world with equality of the sexes in a relationship, the man is much more likely to mate with someone who shares his qualities of mind. I'm not saying I believe this is what is happening. I'm just noting that this criticism of the women's movement is lurking inside Baron-Cohen's theory of autism.

IN THE COMMENTS: People scramble to deny what must not be permitted to be true!

ADDED THOUGHT: We shouldn't be afraid to discover the truth. If there is, in fact, something like an "S brain" and if the offspring of two "S brain"ers has a high risk of autism, the solution would not be to exclude women from the scientific workplace (obviously!) or even to discourage two "S brain"ers from marrying. It's just a matter of giving good genetic advice to persons planning to become parents so that they can choose to have children by artificial insemination if they don't think the risk is appropriate. But I don't know enough about autism to have an opinion about whether the condition really is such that we should try to prevent autistic children from being born. It may be that the two "S brain"ers would produce an extraordinary individual, who might be difficult for us to understand but who would bring great gifts into the world, which we should want to see and embrace.


Bruce Hayden said...

I started to read your entry and thought that it looked awfully familiar. I may have commented here earlier that I had recently read a book entitled "The Essential Difference", and it turns out to be by the author of this article.

What might be missed if you don't read his book, is that he is talking about means of bell curves, when he is talking about a male brain and a female brain. Indeed, he includes numerous graphs illustrating this. The mean of the male "sysemizing" bell curve is to the right of the female mean, whereas the mean of the female "emphathizing" curve is to the right of the male mean.

Which ties right into what Larry Summers was saying, that the most outstanding, say, physicists, are out in the extreme tails of the ("systemizing") bell curve, and thus, since the male mean is to the right of the female mean, out in the end of the tail, there are going to be a fair number more males than females.

This doesn't mean that there aren't a lot of good female scientists and engineers out there, and that there can't be quite a few more, but rather that it is likely that males are going to continue to predominate at the Nobel Prize level.

Also note that this isn't an either/or dichotomy. We all fall somewhere on a two dimensional grid. He includes in his book tests for these traits (that I have queried him on). I score quite high on "systemizing", but above average on "emphathizing", despite being male. It is just that, on average, males score higher on systemizing than on emphatizing, and females the opposite.

Bruce Hayden said...

I am not sure if the author's jump to equating autism, and its less severe cousin, Asperger's Syndrome (AS) is as strong as his original point on male and female brain tendencies.

But I did find that part of the book quite interesting from a personal point of view. It is likely that my girlfriend is borderline (but functional) AS. Because of the predominence of males in the ranks of both autism and AS, much more has been done detecting and working with them. It appears that females are often harder to detect, as the author points out at the end of his book. He kindly referred me to a couple of references, written by women (one with AS) that have been quite helpful.

Ann Althouse said...

Bruce: The bell curve of it isn't missing from the article.

Bruce Hayden said...

Agreed. I reread the article before you pointed this out. Sorry.

Bruce Hayden said...

Annpundit asks over at Instapundit:

'DOES "ASSORTATIVE MATING" CAUSE AUTISM? Simon Baron-Cohen theorizes that the condition may result from the mating of two "Type S"-brained individuals.'

Interesting question. I think yes. The author has found that parents of autistic kids score higher on the systemizing tests than average, and that they also have a larger percentage of grandfathers who were both either engineers or scientists.

So, I worry about my grandkids. My daughter has strong systemizing from all four grandparents. The only grandparent who would have been questionable was my father, and, even though an attorney, he tested high enough during WWII to be placed in an engineering program at U. Ill. (where he met my mother, who was the outstanding science student there in 1944). Her father was an artillary officer and chemical engineer. On my ex's side, her father was an electrical engineer, as was her mother's brother. No surprise - we met on a software project.

So, I am going to warn her that if she ends up marrying someone with a similar background, they just might have autistic, or at least AS, boys.

Luckily, my girlfriend had had a hysterectomy long before we ever met. We figure that if we had had the kids we wanted together, that there would have been a decent chance at AS, esp. given that she is probably borderline.

So, this is probably as good an explanation as any as to why certain schools in Silicon Valley have such high incidences of autism and AS.

Bruce Hayden said...

I am not sure that this interbreeding is totally a bad thing. It has been suggested that both Newton and Einstein were at least borderline AS. At the bottom of the article was a link to other related articles, including one that suggested that maybe the problem with "treating" autism and AS, esp. with bright kids, is that it is being done wrong because they misunderstand what is going on, and that if viewed as extreme systemizing behavior, many of the weird and odd behaviors of the autistic become more understandable.

In other words, since there may be a tie between extreme systemizing and Nobel level physics, etc., it may be advantageous for society to deal with this apparent side effect in a more humane and productive way.

StrangerInTheseParts said...
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StrangerInTheseParts said...

Ann said: "In the pre-feminist set-up, men would be more likely to mate with women who would nuture and care for them."

Why necessarily? In the pre-feminist era, all women - S's and E's - had to play the housewife. Many men, I'm sure, sought out a strong Type S to organize the house and children.

Similarly, I think that it's questionable to state that Type S women are so overrepresented in the world of work that they are suddenly scoring a lot more husbands than they used to. One beauty of women's introduction to the work place is precisely the fact that so many Type E qualities have proven to be quite useful in the world of work.

leeontheroad said...

The author of this piece, Simon Baron-Cohen, posits that the increase in autism is "the genetic result of 'assortative mating,'" as two strong systematizers have children together.

This sounds like a bunch of bunk to me, frankly-- as do all theories that rely so heavily on a mix of extrapolated data and gene theories to explain any increase in the incidence and/or diagnois of disorder.

Any hidden criticism of women's professional advancement fails to accoutn for the offspring of "systematizing" women prior to the greater representation of women in the (science and math) professions. What? We used to have children with more Rogerian therapists, before we were allowed to meet intetesting men in labs? Or we only met such folks at MENSA meetings? Silly! And what of the fact that workign class women have worked with men in the modern industrial age since its inception: are we assuming such folks are not systematizers? That would be, at best, a Lamarckian fallacy.

Deterministic social biology is always suspicious.

StrangerInTheseParts said...
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Ann Althouse said...

Stranger: You can delete your own post and rewrite. In rewriting, consider that I'm only discussing probabilities, so to point out that something isn't necessarily so doesn't contradict what I've said.

Bruce Hayden said...

I think that the point is that one of the best ways to meet your future spouse is in the workplace. But that means that if you are working in a job that requires a lot of Systemizing, that your mate is more likely to be the same, just from proximity.

As noted, it sure happened to me. I met my ex on a software project. We are both fairly high "S" types, and have such from both of our respective parents. So, no surprise that our daughter is also a high "S" type, though I think she has a lot more "E" than her mother.

And I think that she is attracted to "S" types. The guy she was hot for the last two years of middle school was the one person in her grade who could beat her in math.

So, the worry is that because of proximity, the number of high "S" types marrying each other is apparently increasing, maybe dramatically, and possibly could be resulting in an increase in autism and/or AS.

Menlo Bob said...

Assortive mating could also be the result of meeting a mate in other situations not limited to work. It seems likely that large university departments collect people differently than small colleges. Or that attending graduate schools increase the likelihood. Might not knowing this give potential partners a rational basis for a more varied social life?

Bruce Hayden said...

I agree with the Annpunidit here. We are really only talking possibilities here. I have seen concerns that there has been a statistically significant increase in diagnosis of autism and AS in certain Silicon Valley communities, and this would potentially answer that, assuming that this phenomenon exists in the first place, etc.

Bruce Hayden said...


Agreed. That is one reason that I intend to mention this in a couple of years when my daughter goes away to college. She may ultimately end up with another high "S" type, but if she does, I want her to know the potential ramifications, assuming that this theory is correct.

SteveR said...

The idea that there is a genetic link to autism is worth considering. (I'm sure if it proves true Bobby Kennedy, Jr. will find other windmills to tilt against). The science, as Leeontheroad suggests, will be difficult, but its an interesting idea. My own limited experience tends to support the link, FWIW.

BarbO said...

I don't know--I have a feeling that this study could end up showing a profound link between the high powered ultrasound devices currently in use, and autism. The recent increase in autism is so dramatic that it is reasonable to believe it is related to something very widespread--like the use of ultrasound.

Bruce Hayden said...


Or, alternatively, it may be attributable to our increased ability to diagnose the condition.

Ann Althouse said...

Bruce: That's just about what I was going to say. I'll just add that we may be misdiagnosing and have decided to define the range of normal differently, perhaps because there are treatments and people with a financial interest in providing them.

BarbO said...

Bruce, you're right that there could be several factors at work. But the increase in autism does appear to be real--take a look at

A key summary statement from that website says: "You can review the most comprehensive study that I am aware of on the epidemic of autism, done by the MIND Institute in California: Report to the Legislature on the Principal Findings from The Epidemiology of Autism in California: A Comprehensive Pilot Study.

The study, led by Dr. Robert S. Byrd, section chief of pediatrics at the University of California at Davis Children's Hospital, issued its report on August 17, 2002. It concludes there is "no evidence that loosening in diagnostic criteria contributed to an increase in the number of children with autism," and that, therefore, "some, if not all, of the observed increase represents a true increase in cases of autism.""

StrangerInTheseParts said...

Baron-Cohen's thesis is that Type S couples are more likely to make autistic children. There is a currently a major spike in the incidence of autism. So, it follows that a lot more Type S women are getting married and having kids now.

Posters here are attributing the rise in Type S female marriagability to women entering the workforce where suddenly men value their Type S qualities as more compatible.

I believe that those same Type S qualities were very desirable in pre-feminist women. Type S women have ALWAYS made 'good wives' - they keep the house in order and raise children in a orderly, systemetized way. They would have snagged as many partners under the old mating systems as they do now when they can prove themselves at work.

knoxgirl said...

This article from Wired: "The Geek Syndrome" is a really fascinating read about the increase of cases of Autism and Aspergers, especially in the Silicone Valley. Seems to suggest that "geeks" who meet and mate tend to produce children with these disorders.

HaloJonesFan said...

My brain is Type R. It has fiberglass skirts, a big plastic spoiler, and fancy chrome headlights.

HaloJonesFan said...

My thoughts on the autism issue are that autism has become trendy, even fashionable. It's similar to dyslexia ten years ago, or ADD five years ago; the things that get kids defined as "autistic" are the same things that they've always been doing, except now we have a new explanation of why they're doing it. Kids in 1995 were rambunctious brats because they couldn't read. Kids in 2000 were rambunctious brats because their brains had chemical imbalances. Kids in 2005 are rambunctious brats because they're autistics with "socialization problems" who are going into "avoidance routines".

Thirty years of hippy-trippy "children are just small adults" attitudes have resulted in the belief that when a five-year-old runs around the house screaming at the top of his lungs, there is something wrong with him.

Ann Althouse said...

Stranger: I question whether an extreme S type would be good at dealing with children. And it's unlikely that an extreme male S would find and manage to get together with an extreme female S outside of a very specialized workplace, especially considering the rarity of such females.

knoxgirl said...


Sam Chevre said...

Feminism may be part of the explanation, but I suspect that increased levels of assortive mating (spouses with similar personalities) are significantly related to people finding spouses in different settings than before.

If (as used to be typical) you marry someone who you met in high school, through church, through family, etc, you are choosing from a pool of partners that is not selected on systematization grounds. If (as is now more common) you marry someone you met in college, in grad school, or in the workplace, you are choosing from a pool that is to some extent filtered on systematization ability. Thus, partners are more similar to one another, even with no change in people’s preferences.

Roger Sweeny said...

You can believe that increased autism is caused by increased assortative mating and that this is caused by more women working and not yet blame feminism or the women's movement.

If you don't think feminism or the women's movement are responsible for more women working.

An alternative theory holds that more and more women worked because technology turned "homemaking" into a short-term and/or part-time occupation. That in effect men refused to support women who planned to stay out of the workforce, and feminism responded by saying, "You can't fire us; we quit."

Of course, nowadays, just about any woman who told a potential mate that she planned never to get a paying job, would soon be looking at his receeding back.

Pastor_Jeff said...

Has anyone actually determined that autistic or AS children are more likey to have two type-S parents, or is this just the author's theory?

Ann Althouse said...

Roger: I think there are a lot of men who like the idea of a stay-at-home wife. And there are also many women, including women who could do well professionally, who think devoting oneself to raising children and keeping house is honorable. The man you describe as everyman doesn't deserve a good wife -- working or not.

Smilin' Jack said...

I question whether an extreme S type would be good at dealing with children. And it's unlikely that an extreme male S would find and manage to get together with an extreme female S outside of a very specialized workplace, especially considering the rarity of such females.

For this theory to work they don't have to "be good at dealing with children," they just have to have them.

Another aspect of feminism that may contribute here is that it is now more acceptable for girls to display S-traits such as being good at math. They used to be told it would be off-putting to boys if they displayed such traits, and it probably is to E-boys, but it's more attractive to S-boys. So now liberated S-girls are both less attractive to E-boys and more attractive to S-boys. And displaying their S-traits openly makes it easier for S-boys to find them--all conditions ripe for assortative mating. In nature this often results in one species splitting into would be so cool if that happened to us, just because it would drive the creationists and "ethicists" crazy.

Bruce Hayden said...


I no longer have the author's book (it was a library book), but the second half of the second page of his article implies that they have done qualitative research on this and found that autistic kids have parents that tend to be more "S" than average. I must again put in a plug for his book: "The Essential Difference: The Truth About the Male and Female Brain." You may not agree with everything he says, but it is thought provoking.

Bruce Hayden said...

I think that you still cannot discount assortive mating. Until the last third of the 20th Century, you just weren't going to high "S" type females spending all their time with high "S" type males, esp. as you do now. You just didn't have the filtering that you do now, with some jobs absolutely requiring this.

I think back to my software days, and almost all of us were high "S" types. You couldn't do the job otherwise. The one guy I worked with who didn't excell at this, happily went into management.

Even as we went into the 2nd half of the 20th Century, we didn't have all that many jobs that absolutely require this type of mind. Now we do.

During the 15 years I spent in software, all of my girlfriends were met at work, and I will suggest, all were significantly above average in Systemizing. They were just the women I saw on a day to day basis.

Roger Sweeny said...


You're right. I spoke too sweepingly. However ...

"Many men like the idea of a stay at home wife." They also like the idea of eating less and exercising more. Okay, there I go all sweeping again.

Many men like the idea of a stay at home wife, in a large house, driving several nice cars, taking nice vacations and eating in nice restaurants. When reality forces them to cut back, what's often cut is the stay at home part.

And, yes, many women feel that "raising children and keeping house is honorable." But they run up against the same problem, especially since the rise of two-income families has significantly raised the price of houses.

I don't mean to make these people out to be especially selfish or dishonorable. But a one-income family can do considerably less than a two-income family. If those two-income people were your peers, it takes a special couple not to feel deprived, and to stick with the one-earner plan.

Ann Althouse said...

Roger: There are a lot of extra expenses involved when both parents work, such as childcare and more expensive meals as well as the additional clothing and commuting expenses that working entails. If the stay-at-home person puts effort into home cooked meals and smart shopping, the one-earner family could come out ahead.

Kathy Herrmann said...

I question whether an extreme S type would be good at dealing with children. And it's unlikely that an extreme male S would find and manage to get together with an extreme female S outside of a very specialized workplace, especially considering the rarity of such females.

I don't think extreme S's would be but mid-range S types would. The mid-range folks would provide structure and consistency. Also, their lower empathy might be advantegeous to avoid too much emotionalism, helping them stay above the fray of, for example, a child throwing a temper tantrum.

Of course, I'd agree that it's beneficial to have at least one parent bring empathy into child-rearing.

Kathy Herrmann said...

I don't know that I buy that more S-type couples find each other now than in the "old days" mainly because I believe to a large degree like attracts like, whether two folks find each other at church, school, or the office (and for those that mention opposites attract, I'd contend opposites are still "likes" but of the opposite polarity).

But let's assume for the moment that the scientific hypothesis is true -- that two S-types have a higher likehood of producing autistic progeny. The question still becomes one of cause and effect.

Has the rise in auticism come from more S-type matings? Is there something different about today's S-type folks than in the past (male or female)? For example, the NYT article mentioned...

It has also been found that the amount of prenatal testosterone, which is produced by the fetus and measurable in the amniotic fluid in which the baby is bathed in the womb, predicts how sociable a child will be. The higher the level of prenatal testosterone, the less eye contact the child will make as a toddler, and the slower the child will develop language. That is connected to the role of fetal testosterone in influencing brain development.

Is it possible, for example, that some of today's S-type woman are more "S'y" these days because they spend much more of their time in pursuit of left-brained activities? And if so, might that stimulate a higher prenatal testosterone level in their children?

I think these are the sorts of questions, and more, that need exploration before anyone can make more definitive statements. Although starting with anecdotal curiosities is as good a place as any to start.

Bruce Hayden said...

Roaring Tiger,

You do make some good points. Interestingly, one study I saw awhile back theorized that male homosexuality may be a result of lower than normal prenatal testosterone at certain critical points in gestation - possibly due to maternal stress.

So, the author might be seen as proposing two different theories, one hormonal based, and the second genetic. Or, maybe they aren't conflicting. Obviously, we don't have enough information yet.

One reason that I do question whether more right brain activity in girls is the cause of more "S" type women is that both my mother and her aunt were extrordinarily good at math, at a time when this was not considered proper female behavior. That great aunt got her master's from Columbia at a time (1925) when she was the only woman in the math department.

Bruce Hayden said...

As for parenting, just remember that Systemizing and Emphathizing are not mutually exclusive. Someone may be higher than average in both, or in neither.

But this does bring up my girlfriend, who, as noted above, is probably borderline AS. She gets so frustrated with her daughter. She asks, "Doesn't she think these things through? Its almost as if she is parenting totally on emotion". Well, her daughter probably is, while her mother never did anything as a parent that she had not thought through thoroughly.

vbspurs said...

Dear Lord, Jung and Myers-Briggs by any other name...

I don't know, Ann, this also sounds a bit of a stretch to me, but I would have to see Baron-Cohen's data for a more cogent response (and yes, I am aware that as Med School student I should be able to parse together a good reply, but hey, I'm on holiday).

In the absence of anything pertinent to say which hasn't been covered above already, I have two observations:

Simon Baron Cohen...any relation to Sacha Baron Cohen, aka Ali G?

In fact, this theory might be on to something, as one of the topics I recall from having done "diseases" in my second year is that Autism is more prevalent in children of male engineers, than in any other professional job category.

And I've always thought that engineers were the ultra-alpha males of the intellectual world. *shrug*

BTW, my great-grandmother was one of the first OB-GYNs in Britain, and her daughter-in-law, my grandmother, was a lawyer.

My dad is insane, but he's not autistic.

I think we need to see that data.


Bruce Hayden said...


I would suggest starting with his book that I cited earlier (see the first post) and is cited in the article. He had voluminous end notes, but don't remember off hand how well this section was documented - not being a researcher, I typically don't read them.

Eddie said...

What level of risk are we talking about here? My wife and I are both Engineers, and we have 3 children, none of which are Autistic. On the flip side Her sister (A Social Worker) has an autistic child with her Art History major Husband. Are we the exception that proves the rule? Are we looking at one in 100 births, one in 1000, higher or lower?

Roger Sweeny said...


It is certainly possible that all the money brought in by a spouse working can be spent on working expenses for that spouse. But it is extremely unlikely.

The fact that the working spouse will no longer have as much time and energy for careful shopping and cooking will also result in spending more money.

But for the vast majority of people, two earners means significantly more disposable income than one earner.

vbspurs said...

Bruce, thank you for the tip.

I looked up The Essential Difference by Simon Baron-Cohen in my Med School library, but no luck.

Fortunately, the public library had it, and I will place a hold on the book ASAP.

Curiously, though there are 10 copies available in several branches, look at how one was labeled:

Fiction - shelved by Author 155.33 BARO In Library

Nonfiction 155.33 BARO In Library




Judith said...

I don't think it's women in the workplace so much as women in high-tech. There was a spate of articles a few years ago about the high rate of autism in silicon valley and other high-tech enclaves. geeky men who previously wouldn't have a chance at finding an appropriate mate marry geeky women, and produce autistic kids.

DLacey said...

The testosterone theories seem contradictory, unless you could test that men with AS are less likely to be homosexual than all men.

I also wonder what "systemizing" vs "empathizing" really measures.

I've also read that autism or AS may be more common if the families of the parents contain histories of bipolar disorder (

I don't think the "male brain" "female brain" relates much at all to autism, except in that the same factors that cause it also cause autism to be more common in males than females. (The greater corpus callosum in females, mainly). Female brains are more interconnected and more able to compensate for the autism (as for most problems, eg left-handedness which can be caused by minor brain damage, and is less common in females).

Autism's resemblance to "extreme male brain" is no more makes it having to do with assortive mating of "male brain" types than borderline personality disorder's resemblance to "extreme female brain" means that is a result of assortive mating of "female brain" types.

However, it is possible, in fact I think it's likely, that genetic tendencies toward bipolarity are somehow linked to certain mental abilities - which give a boost to a subsystem of the Systemic part of the brain - and cause other changes that may make a person more likely to be autistic or bipolar. It's also possible that such people are, while rare, attracted to one another. Modern technology is the chief enabler of these folks finding each other - they use it most often and most adeptly. Nothing to do with feminism either.

Jeremy Pierce said...

I think there's a lot of merit to thinking of autism as a heightening of typically male strengths and weaknesses and a lowering of typically female strengths and weaknesses. I don't think this can fully explain autism. My wife is not a systemizer of the sort Baron-Cohen is talking about. The typical autistic Myers-Briggs profile would be an extreme ISTJ. My wife is INFP. On all traits except introvertedness, she's the opposite. Yet we have one son diagnosed with autism and another who seems to have enough symptoms that he might be as well. I certainly think there's a genetic issue, but it can't be just from when two people who are strong systemizers have children together. Her parents aren't strong systemizers either. Her dad is maybe middle of the road, and her mom is like her.