Autism

             "Although a single cause of autism is not known, current research links autism to biological or neurological differences in the brain. In many families, there appears to be a pattern of autism or related disabilities, which suggests that there is a genetic basis to the disorder." (Autism Society of America, 2001) Among brothers and sisters of autistic patients, the rate of both autism itself and milder related symptoms is 50 to 100 times than average. The matching rate for autism in identical twins is 65-90%. According to some studies, many apparently normal parents of autistic children have undiagnosed mild autistic symptoms. There have been many outdated theories about the cause of autism, which have all been proven false. Firstly, autism is not a mental illness. Also, psychological factors in the development of the child have not been shown to cause autism. However, there is evidence that a virus can cause autism. There is an increased risk in having an autistic child after exposure to rubella during the first trimester of the pregnancy. There is also growing concern that toxins and pollution in the environment can also lead to autism. Scientists have also identified chemicals in the brain that may be involved in autistic disorder. As a normal brain develops, the level of serotonin, a chemical found in the brain, declines. In most children with autistic disorder however, the serotonin levels do not decline, which could be a cause of autism. It must be recognized that autism is a set of symptoms and may have many causes. But it is undoubtedly a biologically based disorder. Autism seems to be the "final common pathway" of numerous disorders that affect brain development.
             Any child with a delay or regression of language or an abnormality of social interaction beginning prior to the age of three may be suspected of being autistic. Autism, which affects thought, perception and attention, is not just one disorder with a well .