Autism is not a disease, a mental illness, or a behavior problem. It is a complex disorder of the central nervous system that affects many different expressions of brain development, including social interactions and communications. Most people with autism have problems communicating, forming relationships, and interpreting and responding to the external world.
Autism begins in early childhood. The signs and symptoms of autism may become apparent by the time the child reaches the age of 18 months, and they almost always become apparent by the time the child is 3 years old. Autism persists throughout the person's lifetime, although many people are able to learn to control their behavior to some extent.
Autism occurs at all intelligence levels. Although about 75% of autistic individuals have an intelligence quotient (IQ) below average, the other 25% have average or above average intelligence. About 10% have high intelligence in a specific area such as mathematics.
Autism is a spectrum disorder. This means that the symptoms and other manifestations of autism vary widely from person to person. They also vary widely in severity.
Some people are affected fairly mildly; many of these learn to live independent lives. Others are more severely affected and require lifelong care and supervision.

Autism is sometimes classified as a group of disorders known as autism spectrum disorders. All of these disorders are characterized by problems with communication, social interaction, and atypical, repetitive behaviors.

One example is Asperger syndrome, a condition similar to autism but without the problems in language development.

Autism is classified by the American Psychiatric Association as one of a group of disorders known as pervasive development disorders, which includes, besides Asperger syndrome, the conditions childhood disintegrative disorder, Rett disorder, and general pervasive developmental disorder. Autism is one of the most common developmental disorders. At least 1 in every 1000 people in the United States is affected, and the incidence appears to be increasing.

As many as 1.5 million people in this country may have some form of autism.

It affects all races, ethnic groups, and socioeconomic levels.

Boys are 3-4 times more likely than girls to have autism. There is no cure for this oft-devastating condition. There is good news, however. A generation ago, most children with autism were institutionalized. This is no longer the case.

Our improving understanding of autism has shown that, regardless of the severity of the condition, children with autism can, with appropriate treatment and education, learn and function productively.

Early diagnosis is essential for implementing appropriate treatment and education at an early age, when they can do the most good.


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