What is Asperger's syndrome?

Asperger's syndrome is one of a group of childhood developmental problems known as pervasive developmental disorders (PDD). These disorders include Asperger's syndrome, pervasive developmental disorder — not otherwise specified, and autism.

Pervasive developmental disorders share a set of common features, which include:

  • Impaired or abnormal development of social interactions.
  • A marked restriction of activities and interests.

What causes these disorders?

In the 1940s, these developmental problems were thought to be caused by parents who were distant and unemotional with their children. By the 1980s, it was known that pervasive developmental disorders are caused by a problem with the functioning of the brain. To date, however, the exact cause of pervasive developmental disorders remains unknown despite extensive research. Currently available testing, such as blood tests or magnetic resonance imaging (MRI) scans, have failed to reveal any consistent abnormalities in the brain.

Sometimes, pervasive developmental disorders run within families. This occurrence suggests that these disorders may have a genetic component. However, pervasive developmental disorders also occur in families that have no history of developmental disorders.

What are the main features of Asperger's syndrome?

Social interaction

Limited reciprocal social interaction is a main feature of Asperger's syndrome. These individuals often struggle with the use of nonverbal behavior, the development of peer relationships, sharing their interests and enjoyment, and emotional and social reciprocity.

Repetitive and stereotyped behavior

Individuals with Asperger's syndrome often demonstrate encompassing preoccupations, restricted pattern of interests, inflexible adherence to routines, repetitive motor mannerisms (such as hand flapping, rocking), and a preoccupation with parts of objects.


Many people with Asperger's syndrome have above average cognitive abilities and are extremely talented in certain areas. The areas of exceptional skills often involve functions of the right hemisphere of the brain, such as skills with numbers, math, computers, and music.

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