Detected in approximately four to five of every ten thousand births (Powers 10), autism is a widely misunderstood disease. General knowledge of autism, often mistaken, is derived from films such as Rainman. These unrealistic films feature autistic characters who are portrayed as being excessively intelligent. In reality, however, only twenty percent of people diagnosed with autism have average or above-average intelligence ("Autism Primer” 2). Actually, the majority of autistic people suffer varying degrees of mental retardation. A lifelong developmental disability, autism is a disease which affects the way people see, hear, relate, and communicate to others around them. Although the disease is incurable, progressive steps can be taken to help an autistic person function more independently in society.
Autism is categorized as part of a larger group of disabilities called Pervasive Developmental Disorders, or PDD's. Among other PDD's, such as Down syndrome and schizophrenia, autism rates as the fourth most common (Powers 10). General symptoms of PDD's include impaired social interaction and communication skills. Symptoms, however, range on a continuum from mild to severe. While mild behavior is in no way dangerous, severe behavior can be very aggressive and can even result in self-injury.
No single factor has been determined as a cause for autism, but researchers have come up with several theories. One probable cause is an abnormality in gene structure, which is acquired genetically. These genetic conditions affect brain development. Another possibility is that autism is the result of a diet lacking some vitamins, minerals, and amino acids. Both of these hypotheses can contribute to neurological abnormalities. The affected areas of the brain include the cerebellum, hippocampus, and amygdala. The neurons in this part of the brain develop to be smaller than normal, and the nerve fibers are stunted.