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Autism
Definition:
Autism is a complex developmental disorder that appears in the first 3 years of life, although it is sometimes diagnosed much later. It affects the brain's normal development of social and communication skills. Autism is a spectrum that encompasses a wide range of behavior. The common features include impaired social interactions, impaired verbal and nonverbal communication, and restricted and repetitive patterns of behavior. Text Continues Below
The symptoms may vary from moderate to severe. Two related, milder conditions are Asperger syndrome and "pervasive development disorder not otherwise specified" (PDD-NOS). Alternative Names:
Pervasive developmental disorder - autism
Causes, incidence, and risk factors:
Autism is a physical condition linked to abnormal biology and chemistry in the brain. The exact causes of these abnormalities remain unknown, but this is a very active area of research. There are probably a combination of factors that lead to autism. Genetic factors seem to be important. For example, identical twins are much more likely than fraternal twins or siblings to both have autism. Similarly, language abnormalities are more common in relatives of autistic children. Chromosomal abnormalities and other neurological problems are also more common in families with autism. A number of other possible causes have been suspected, but not proven. They involve digestive tract changes, diet, mercury poisoning, vaccine sensitivity, and the body's inefficient use of vitamins and minerals. The exact number of children with Autism is not known, but estimates suggest that roughly 1 in 1,000 children are affected. Autism affects boys 3 to 4 times more often than girls. Family income, education, and lifestyle do not seem to affect the risk of autism.
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