Cornell study on TV and autism

A Slate article discusses a new Cornell University study that suggests a significant link between TV and autism in children:

The researchers studied autism incidence in California, Oregon, Penn-sylvania, and Washington state. They found that as cable television became common in California and Pennsylvania beginning around 1980, childhood autism rose more in the counties that had cable than in the counties that did not. They further found that in all the Western states, the more time toddlers spent in front of the television, the more likely they were to exhibit symptoms of autism disorders.

[...]

The Cornell study makes no attempt to propose how television might trigger autism; it only seeks to demonstrate a relationship. But Waldman notes that large amounts of money are being spent to search for a cause of autism that is genetic or toxin-based and believes researchers should now turn to scrutinizing a television link.