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Could there be something to this strange piece of statistical derring-do? It's not impossible, but it would take a lot more research to tease out its true significance. Meanwhile, it's hard to say just what those correlations measure. "How do you know, for instance, that it's not mold or mildew in the counties that have a lot of rain?" says Vanderbilt University geneticist Pat Levitt. How do you know, for that matter, that as counties get more cable access, they don't also get more pediatricians scanning for autism? Easterbrook, although intrigued by the study, concedes that it could be indoor-air quality rather than television that exerts an influence. Moreover, says Drexel University epidemiologist Craig Newschaffer: "They ignore the reasonable body of evidence that suggests that the pathologic process behind autism probably starts in the womb."
The week also brought a more definitive--though less splashy--finding on the causes of autism, published in the Proceedings of the National Academy of Science. A team led by Vanderbilt's Levitt found that a fairly common gene variation--one that's present in 47% of the population--is associated with an increased risk of autism. People with two copies of the gene have twice the average risk of autism. Those with one copy face a slightly increased risk. The gene is intriguing because it codes for a protein that's active not only in the brain--the organ most affected by autism--but also in the immune system and the gastrointestinal tract, both of which can function poorly in many people with autism.
As with cancer, there are probably many routes to autism, involving diverse combinations of genes and noxious influences. Could Teletubbies be one of them? Conceivably, but more likely the trouble starts way before TV watching begins.
A version of this piece was one of our most e-mailed stories last week. Check out more by Claudia Wallis on autism on time.com