If cases of autism are on the increase, as some believe, here's one provocative explanation: Blame the rise on marriages between like-minded people, whom psychologist Simon Baron-Cohen of Cambridge University in the U.K. calls "systemizers."
Baron-Cohen argues that autism and related conditions like Asperger's are manifestations of what he calls the "extreme male brain": one with weak social skills and a strong tendency to "systemize," or think according to rules and laws. In a study of 1000 U.K. families, he has reported that the fathers as well as the grandfathers of children with autism spectrum conditions are more likely to work in professions such as engineering. And the mothers are also likely to be systemizers "with male-typical interests," he says.
Baron-Cohen, whose theory is in press at the journal Progress in Neuropsycho-pharmacology and Biological Psychiatry, says he and colleagues are performing genetic studies, collecting subjects, and conducting population surveys in systemizer-heavy areas, such as Silicon Valley, to test the idea that techies marrying each other is raising autism rates.
Some balk at the idea. Psychologist Elizabeth Spelke of Massachusetts Institute of Technology says there's no good evidence for an "inborn, male predisposition for systemizing." But psychiatrist Herbert Schreier of Children's Hospital in Oakland, California, believes the intermarriage of techies "probably does account for why you have pockets of high autism around Stanford and MIT." Drawing on his own practice, he adds that fathers of children with learning disabilities have a disproportionate tendency to be engineers or computer scientists.
