Sidebar text: Are Rates of Autism Increasing? The idea of an “autistic epidemic” has been expressed in both the psychological literature and in the news media. Yes, rates of autism have increased; this is in a large part due to better detection. Research has also documented that as rates of autism have risen, rates of mental retardation (also known as Intellectual Deficiency) have decreased. In other words, psychologists and other mental health diagnosticians are more likely to diagnosis autism – perhaps in part due to the increasing social acceptance of a diagnosis of autism as compared to mental retardation. One controversial issue is that rates of autism are increasing due to mercury in children’s vaccines. To date, research has clearly demonstrated that there is no connection between vaccines and autism. In fact, rates of autism have actually increased in countries that no longer use of mercury in vaccines.