A group of researchers has suggested a possible cause for autism: television.

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An autism diagnosis is something that every parent fears. It can mean a life of self-contained struggle, limited growth and social incapacitation for a child, and there is no cure. According to the National Institute of Mental Health, approximately one in 300 children in the United States suffers from autism-spectrum disorders (ASD). According to the Cornell and Purdue University researchers who released a study connecting toddler-age TV viewing with autism occurrence, that number is more like one in 175.

When an infant or toddler exhibits abnormal

social behavior such as refusing eye contact, withdrawing from outside stimulation and obsessively focusing on a single object and shows slow, non-existent or suddenly regressed psychological development in areas like speaking and understanding language, the wide variety of autism-spectrum disorders becomes a possible explanation.

Autism is the most severe form of these disorders, and an autistic child leads a fairly limited life (at least from an outside perspective), unable to effectively communicate, form emotional connections and manage the stresses of daily life. There are other, milder disorders like Asperger syndrome in which the child can live a more normal life while dealing with relatively manageable social problems.

Studies have shown that ASD affects multiple major brain areas, including the cerebellum, cerebral cortex and brain stem. Science has been trying to uncover the cause of autism for decades, focusing on areas like abnormal brain development, a mutated gene called MET that increases the risk of autism (but does not seem to cause autism on its own), childhood-vaccination ingredients (which have been almost entirely ruled out as a potential cause) and every other potential biological trigger under the sun. But a group of researchers out of Cornell and Purdue has focused on a very different possible cause: television. And while headlines are announcing "TV Causes Autism," that's not an accurate representation of what the study found.

Here's what the researchers actually discovered:

  1. Autism-diagnosis rates began to increase dramatically around the same time that cable TV was introduced in the United States, and counties with greater access to cable TV saw greater increases in autism diagnosis.
  2. Autism-diagnosis rates have increased faster in rainier parts of the country.

The researchers related the second finding to television by referring to other studies that suggest that children in rainier climates tend to spend more time indoors than children in less rainy climates; and children who spend more time indoors tend to watch more TV.

What the study did not discover is that TV causes autism. The researchers behind the study believe their findings indicate that watching a lot of television before the age of three can trigger the development of autism in children who are already at risk for the disorder, such as those who carry the supposed "autism threat" mutation on the MET gene. The study did not find that children who are at risk for autism will be saved from the disorder if they're not allowed to watch television. To read the full findings, see Cornell University: Does Television Cause Autism?.

 Despite the dire headlines, probably the strongest finding to come out of the study is that autism researchers might do well to expand their areas of investigation. Until now, research has focused mostly on biology -- the brain and DNA structures and how they may be affected by such processes as genetic mutation, abnormal childhood development and the introduction of foreign chemicals into the body. What this new study suggests is that other, non-chemical environmental factors could provide at least partial clues to the autism puzzle that so far have been very well hidden.

For more information on TV and autism, ASD and related topics, check out the links on the next page.