I am surprised you don't know about this studyThe study's findings suggest a quantitatively important role for television viewing in autism diagnoses. The authors estimate that 38 percent of autism diagnoses can be attributed to the additional television watching that occurs due to precipitation and that 17 percent of the increase in autism rates over a twenty-year period is due to the growth of cable households and subsequent increase in early childhood television watching.http://www.nber.org/bah/winter07/w12632.html