Tracking Causes of Autism Back to the Womb
ALEX CHADWICK, host:
This is DAY TO DAY. I'm Alex Chadwick.
Coming up, in Utah, touring Canyonlands National Park with a guide who's worth the trip all by himself.
First, a new theory on what causes autism, the disorder that makes children, mostly boys, socially withdrawn even thought they're highly capable in other ways. Now British scientist Simon Baron-Cohen has come up with a theory that he calls extreme male brain. It's say autism may result from too much testosterone. He spoke with DAY TO DAY's Madeleine Brand.
MADELEINE BRAND reporting:
Simon Baron-Cohen, welcome to DAY TO DAY.
Mr. SIMON BARON-COHEN (Scientist): Thank you very much. It's a pleasure to be on the show.
BRAND: Now what does that mean, extreme male brain?
Mr. BARON-COHEN: Well, in the general population, we find differences between the typical male and typical female. For example, males seem to be more interested in systems and females seem to be more interested in people and particularly people's emotions. So if you take an extreme of that, it would be somebody who's very, very interested in systems but maybe has difficulty reading other people's emotions.
BRAND: And those, in fact, are the symptoms of autism.
Mr. BARON-COHEN: Well, that's right, so that's why we're beginning to look at whether autism might simply be an extreme of the sex differences you see in the general population, an extreme of the male brain.
BRAND: You have looked at both the physical and the psychological differences in the male and female brains. How do you map that?
Mr. BARON-COHEN: Well, we measure this through a range of difference psychological tests, and males tend to report they're more interested in systems like maps or mathematics. And questionnaires relating to empathy, like, you know, how quickly you can pick up on what somebody else is feeling or thinking, where women tend to score higher than men.
BRAND: And can that not be attributed to socialization?
Mr. BARON-COHEN: Sure. I mean, socialization is bound to be important in shaping these sex differences. But what we've found is if you go back in time to when children are very small, you still find these sex differences even before experience or socialization has had much chance to have an effect. Little girls will look longer at a human face, and little boys will look longer at a mechanical mobile suspended above the crib.
BRAND: And do you posit that that may come from prenatal testosterone, particularly that the more prenatal testosterone the fetus is bathed in, the more prevalent the signs of autism?
Mr. BARON-COHEN: Yeah. I mean, we've done some research using amniocentesis where you take some of the amniotic fluid from the womb, and as you say, you know, the more testosterone the fetus is producing, the less eye contact the child makes after they're born and the slower they are to develop language.
BRAND: Well, what about environmental factors? Many parents think that mercury, for example, might be a cause of autism.
Mr. BARON-COHEN: Yeah, and I'm following that research; it's mostly coming out of the States, and it's very interesting. But over and above that, my theory suggests that the parents of children with autism may be strong systemizers themselves, and the idea here may be that when two strong systemizers marry and have a child, that may influence the risk that the child will have autism.
BRAND: So the mother would exhibit these traditionally male characteristics, as you describe them.
Mr. BARON-COHEN: That's right.
BRAND: And how would your theory lead to a cure?
Mr. BARON-COHEN: Well, I would use the word `intervention' and `support,' because many people with Asperger syndrome, for example, would become resistant or even offended by the idea that they need to be cured because they simply want to be recognized that they're different. But having said that, individuals who are much more disabled--they may well be very positive about the idea that treatments could remove some of these more disabling symptoms.
BRAND: You would simply remove some of the testosterone?
Mr. BARON-COHEN: Well, I think we should be clear at the moment that the testosterone research is really aimed at trying to understand the causes of the condition. But you're right that in years to come, if that theory is confirmed, it could lead to a hormonal treatment. But my own perspective is that this would be ethically very controversial because it could lead to an intervention in the womb where changing an individual's hormone levels could change the nature of their personality and the way they think.
BRAND: Simon Baron-Cohen is the director of the Autism Research Centre at Cambridge University. He's also the author of "The Essential Difference: The Truth about the Male and Female Brain."
And, Simon Baron-Cohen, thank you very much for joining us.
Mr. BARON-COHEN: Thank you very much.
CHADWICK: And thanks to DAY TO DAY's Madeleine Brand for that interview.
I'm Alex Chadwick. There's more just ahead on DAY TO DAY.