Autism

DSM-IV describes autistic disorder as consisting of twelve possible symptom areas in three areas of development. These include social—marked impairment in nonverbal behaviors, failure at peer relations, impaired sharing of pleasure and lack of socioemotional reciprocity; communication—delay in communication without gesture compensation, impairment in conversational ability, stereotyped and repetitive language, and lack of imaginative play; atypical activities and interests—restricted interests, nonfunctional routines and rituals, and preoccupation with parts of objects. To be diagnosed with autistic disorder, an individual must exhibit at least six out of the twelve symptoms, with at least two being in the social domain, along with one each in the communicative domain and the domain of atypical activities and interests. Individuals with at least one symptom each in the social and communicative domains, but fewer than six symptoms overall, are classified as PDD-NOS as are individuals without symptoms in the domain of atypical activities and interests. The criteria for Asperger's disorder uses the same social criteria as autistic disorder, but requires at least one symptom in the area of atypical activities and interests, as well as normal age of onset for language.