History and Background

first described autism in 1943 [1]. His observations of a small group of children with behavioral symptoms of social withdrawal, impaired language/communication, and obsession with sameness led to recognition of autism as a specific pervasive developmental disor-der. At about the same time, Austrian psychiatrist Hans Asperger independently described similar symp-toms in a small group of children except that the “Asperger ” children were high functioning with bet-ter language and cognitive skills than those described by Kanner [2]. Both Kanner and Asperger used the word autistic to describe the pathology in the chil-dren they observed – a term rooted in the Greek “autos ” (self) and coined by Swiss psychiatrist Eugen Bleuler to describe symptoms in his schizophrenic patients. Before Kanner and Asperger defined autism as a specific disorder, children with autistic symp-toms were most likely classed and treated as mentally retarded or, if they were high functioning, perhaps as schizophrenic. The symptoms described by Kanner and Asperger remain the core diagnostic symptoms for autism and associated disorders. Autism spectrum disorders (ASDs) as specified in the DSM-IV TR (a text revi-sion of the DSM-IV) include autistic disorder (classic autism), Asperger’s disorder, pervasive developmen-tal disorder not otherwise specified, Rett’s disorder