Autism explained: What's sex got to do with it? Part three

A normal 4-year-old child says that Sally will look for the marble where she left it, in her basket. The child may even giggle at the joke on Sally. A kid with Down's syndrome will get it right too. But autistic children don't get it right. They say Sally will look in Anne's box -- because after all, that's where the marble really is. They have no notion, Baron-Cohen discovered, of where Sally might think the marble is. They lack a "theory of mind" -- abstract jargon for the simple realization, which the normal child comes to at around age 4, that other people have thoughts and intentions that may differ from his own. And that figuring those thoughts out helps him to understand what those people say and do.

Baron-Cohen later coined a term for this deficit: "mindblindness." In 1989, Uta Frith proposed that autistic people's inability to derive a theory of mind from their experience of the world was just one aspect of a broader deficit: the inability to draw together information so as to derive coherent and meaningful ideas. Frith's weak central coherence theory explained why people with autism remember strings of nonsense words almost as well as they do sentences, or why they do jigsaw puzzles without the picture: They just don't seek the pattern in a mass of details. "Their information-processing systems, like their very beings, are characterized by detachment," Frith wrote. A rival theory, which has proponents today, attributes the narrow interest in details, as well as other symptoms of autism, to executive dysfunction, a very broad inability to plan, to control impulses and to switch attention as needed to solve a problem.

Neither weak central coherence nor executive dysfunction, though, explain why some autistic people do so well. And in the 1990s, after Baron-Cohen had moved to Cambridge and begun seeing adult Asperger's patients, including many high achievers, at his own clinic, he became increasingly aware of that gap. Furthermore, he says, nobody seemed to be addressing another key fact: Autism affects far more boys than girls. At the Asperger's end of the spectrum, the ratio is about 10 to 1. The sex difference, says Baron-Cohen, is "one puzzle that has been completely ignored for 50 years. I think it's a very big clue. It's got to be sex-linked."

"When I read the newspaper, I am drawn to tables of information, such as football scores or stock-market indices. Strongly agree? Slightly agree? Slightly disagree? Strongly disagree?" -- from the Systemizing Quotient questionnaire.

In The Essential Difference, before getting to his extreme-male-brain theory of autism, Baron-Cohen combs the psychological literature for evidence that normal sex differences in empathizing and systemizing are real and rooted in biology. He expected this claim to be controversial and was surprised and a little irritated when he read, "Didn't we always know this? Didn't our grandmothers tell us this?" Proving with scientific data that sex differences in behavior are innate is notoriously difficult. But Baron-Cohen, understandably enough, spares his popular audience the data. Indeed, the conclusions alone do have a familiar ring. Girls like dolls, boys like trucks. Girls like to gossip, boys like to roughhouse. Girls are more verbal, boys are more spatial, right through the SATs. Girls attack one another indirectly and verbally (which requires them to know how their victim feels). Boys are direct and physical, and when they reach manhood they are far more likely to commit murder -- the ultimate in lack of empathy," as Baron-Cohen puts it.

To read part four of this article click here.