Related Disorders

Abstract

Autism spectrum disorders (ASDs), also referred to as pervasive developmental disorders (PDDs) in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (American Psychiatric Association [APA] 2000) encompass a heterogeneous group of neurodevelopmental disorders with varying etiologies that have been behaviorally defined as having impairments in social communication, reciprocal social interaction, and repetitive, restricted behavior and interests (APA 2000). The spectrum includes autistic disorder, characterized by clear deficits in all three domains; Asperger's disorder, characterized by no significant language delay and average to above average cognitive functioning; and pervasive developmental disorder-not-otherwise-specified (PDD-NOS), characterized by significant social and communication impairments that do not meet full diagnostic criteria for autistic disorder (American Psychiatric Association 2000). According to current diagnostic criteria, symptoms must be present before 3 years of age. Current literature estimates the prevalence of ASDs to be 1:150, or 0.6-0.7%, and even higher estimates of 1:110 have been published by the Centers for Disease Control and Prevention (CDC 2006). It should be noted that, at the time this volume is going to press, the American Psychiatric Association is publishing the DSM-V, which changes several aspects of the diagnostic criteria for autism (American Psychiatric Association 2013). However, this chapter discusses the longstanding previous diagnostic criteria, as these criteria have been the subject of the overwhelming majority of research. (PsycInfo Database Record (c) 2020 APA, all rights reserved)