Topic Overview

Once known as pervasive developmental disorders (PDDs), autism spectrum disorders (ASDs) is an umbrella term used to define a class of disorders.

Disorders that are included in this class are:

• Autism.
• Asperger's syndrome.
• Childhood disintegrative disorder (CDD).

Until recently, people were diagnosed with one of the types of ASD. For example, a person was diagnosed with Asperger's syndrome. Now, the diagnosis of ASD is used, and the severity of the condition is noted. The diagnosis of ASD typically occurs during childhood, but an adult can be diagnosed with ASD.

Some children do not meet the diagnostic criteria for an autism spectrum disorder (ASD) but still may have developmental and behavioral problems that are similar to those found in ASDs. These problems include abnormal sensitivities and unusual behavioral responses to certain situations. In these cases, a diagnosis of unspecified neurodevelopmental disorder may be used.

Children with ASDs have difficulty in areas of social and emotional development, including:

• Developing relationships with other people, including their parents and children their own age.
• Communicating with other people.
• Having unusual behaviors and interests.

The severity of an ASD varies by individual. Severely affected children are unable to function without significant help from parents and other caregivers. Other children are mildly affected and can develop adequate skills to lead independent lives as adults. Many children are affected at levels somewhere between these two extremes.

Autism spectrum disorders are present at birth. But the signs of these disorders may not be noticed until later, usually during the first 3 years of a child's life.