Autism is a complex developmental disorder that affects the brain's normal development of social and communication skills. Common features of autism include impaired social interactions, impaired verbal and nonverbal communication, problems processing information from the senses, and restricted and repetitive patterns of behavior.

People with autism—the core form of the autism spectrum disorders (ASD)—tend to appear indifferent and remote and are unable to form emotional bonds with others. In addition, they will often have unusual responses to sensory experiences. Each of these symptoms runs the gamut from mild to severe. They will present differently in each individual child. For instance, a child may have little trouble learning to read but exhibit extremely poor social interaction. Each child will display social, behavioral, and communication patterns that are individual but fit into the overall diagnosis of ASD.

Children with autism do not follow the typical patterns of child development. In some, signs of future problems may be apparent from birth. Other children develop typically at first, but between the ages of 18 and 36 months, their development stagnates. Parents may notice that they begin to reject social contact, act strangely, and even lose language and social skills that they have already acquired. In other cases, there is a plateau or leveling of progress, and the difference between the child with autism and other children the same age becomes more noticeable.

A recent study of a U.S. metropolitan area estimated that 3.4 of every 1,000 children ages 3 to 10 had autism.

Autism is found in every country and region of the world and in families of all racial, ethnic, religious, and economic backgrounds. This wide range of prevalence points to a need for earlier and more accurate screening for the symptoms of ASD. The earlier the disorder is diagnosed, the sooner the child can be helped through treatment interventions. Pediatricians, family physicians, day-care providers, teachers, and parents may initially dismiss signs of ASD, optimistically thinking the child is just a little slow and will catch up. Although early intervention has a dramatic impact on reducing symptoms and increasing a child's ability to grow and learn new skills, it is estimated that only 50 percent of children are diagnosed before kindergarten.

Autism. Last reviewed 12/31/1969
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