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Autism
is a disorder of neural development, which is impairment of the growth and development of the brain or central nervous system. The symptoms of autism all begin before a child is three years old, however in highly functioning individuals with autism, the signs are often missed. Autism can affect emotions, learning ability and memory and these symptoms usually unfold as the child grows. Autism affects information processing in the brain. How this occurs is not well understood. Autism is but one of three medically recognized disorders in the autism spectrum (ASDs.) The other two are Asperger Syndrome, in which an individual experiences delays in cognitive development and language. The other is Pervasive Developmental Disorder-Not Otherwise Specified, which is diagnosed when autism and Asperger Syndrome have been ruled out due to the individual not meeting the full criteria of either of those disorders. The genetics of autism are complex, but it is believed to have a genetic basis. Research is ongoing and it’s still unclear whether autism is caused by rare gene mutations, or by rare combinations of common genetic variants. There are studies, and much controversy, about whether it’s caused by things in the environment, such as pesticides or childhood vaccines. The vaccine theory lacks convincing scientific evidence at this time. The number of children diagnosed with autism has increased dramatically since the 1980s. However, it’s unclear if this is because there has been an actual increase in the prevalence of the disorder, or if it’s due to changes in the diagnostic practice - therefore more cases are reported and recorded.
According to the Centers for Disease Control and Prevention: If 4 million children are born in the United States every year, approximately 36,500 children will eventually be diagnosed with an ASD. Assuming the prevalence rate has been constant over the past two decades, we can estimate that about 730,000 individuals between the ages of 0 to 21 have an ASD. Studies in Asia, Europe and North America have identified individuals with an ASD with an approximate prevalence of 0.6 percent to over 1 percent. Approximately 13 percent of children have a developmental disability, ranging from mild disabilities such as speech and language impairments to serious developmental disabilities, such as intellectual disabilities, cerebral palsy, and autism.
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