Pub. date: 2008 | Online Pub. Date: April 21, 2008 | DOI: 10.4135/9781412963855 | Print ISBN: 9781412941860 | Online ISBN: 9781412963855| Publisher:SAGE Publications, Inc.About this encyclopedia
Elizabeth R. Purdy
Autism is a neurodevelopmental disability that cannot be diagnosed by any specific biological or medical test. It is organic rather than genetic, developing during the prenatal period. Autism is characterized by a triad of symptoms that include difficulties in social interaction with others, problems communicating with others, and patterns of restrictive, repetitive, and stereotypical interests and activities that are evident before the age of 3. The disorder popularly referred to as autism generally describes the most common form of autism. There is a group of other disabilities of varying severity that are also classified as autism spectrum disorders (ASD). Diagnoses of autism are based in large part on observation. In its most common form, autism is apparent in infancy. In other forms, it may surface after months or even years of apparently normal development. Chromosomal/DNA testing may be useful, particularly if autism occurs along with other disorders such as Fragile ...