Autism explosion half explained, half still a mystery
Why have the numbers of autism diagnoses ballooned in recent decades? Researchers have long claimed that changes to the way the condition is diagnosed are the main cause. But now a series of a studies have shown that diagnostic changes alone cannot account for the increase. They suggest that other causes, perhaps environmental factors, are also contributing to the rise in cases.
"These studies give me the feeling that there must be a true increase in the number of children affected," says Tom Insel, director of the National Institute of Mental Health in Rockville, Maryland.
This analysis may still be a little lacking - such as when it blames older parents for a whooping 11% of the increase in autism because they produce more "genetic mutations" without being able to show how these mutations are causing autism. But it is long past time for researchers to make a serious attempt at figuring out what is going on with autism.