Saturday, May 29, 2010

Higher testosterone levels in fetuses may lead to autism symptoms, new research says

From The Ottawa Citizen in Canada:

Higher testosterone levels in unborn babies can lead to permanent changes in the brain that contribute to the development of autistic traits, new research suggests.

According to British psychologist Simon Baron-Cohen, autism is the result of an "extreme male brain," leading to a mind that is predominantly hardwired for understanding rules, identifying patterns and building systems.

In people with autism, such neurological traits tend to be highly developed. A functioning female brain is largely hardwired for empathy -- the ability to read and respond to another person's thoughts or feelings.

Studies by Baron-Cohen's research team at Cambridge University show children with autistic traits such as low empathy, limited language skills and a highly developed sense of order and routine also tend to have had higher levels of testosterone in the womb.

Baron-Cohen tested his theory by examining the hormone levels of 235 pregnant women who had amniocentesis to screen for any fetal abnormalities. He then followed the children of these women years after they gave birth.

Baron-Cohen discovered that compared to children with normal testosterone levels in the womb, children with high fetal testosterone levels had a smaller vocabulary at age two; by age eight, their mothers also noticed that they had lower-than-average levels of empathy and unusually well-developed abilities to identify patterns and details.

The findings suggest testosterone plays a key role in how the brain develops, Baron-Cohen said Tuesday at an autism conference sponsored by McGill University.

"Testosterone is a very interesting candidate for how the brain might become masculinized in the general population," said Baron-Cohen, who has spent more than two decades studying autism spectrum disorders.

Baron-Cohen is among a growing number of neuropsychological researchers who are taking a fresh look at autism. The condition, they say, shouldn't be thought of as a disease to be eradicated. It may be that the autistic brain is simply different -- an example of the variety of human development.

These researchers assert that the focus on finding a cure for autism -- the disease model -- has kept science from asking fundamental questions about how autistic brains function.

Indeed, Baron-Cohen points to more effective ways to teach people with autism.

For example, his Cambridge team has pioneered the use of DVDs to help autistic children read emotional cues in everyday social interactions. The DVDs, The Transporters ( and Mind Reading (, allow children to see actors demonstrating a variety of emotions. Unlike real life, where social interactions are quick and fleeting, DVDs allow children to study methodically and replay the situations that cause different emotions.

"It's not the natural way that most of us learn about emotions," said Baron-Cohen.

"Most of us learn about emotions through social interaction in the playground or with our siblings, our families. But here, we're suggesting that maybe children with autism, if they're not picking up emotions in the usual way, might find it easier to learn about emotions through computers. And that's because computers are very predictable, they are rule-governed systems so people with autism might prefer to learn in that format."