Order an affordable Custom Written Paper . The onset of the disorder is in infancy or early childhood, generally before the age of thirty months, and males are affected four times as often as females. Autistics can exhibit any combination of these characteristics in any degree. Kanner noticed that autistic infants had a reverse pattern typically observed in normal infants.
Infants are normally interested in social, as opposed to nonsocial environments.
The cause for autism remains unclear, although most neurological studies seem to indicate a dysfunction in the brain as a possible reason. Autism has been found in children with brain abnormalities such as congenital rubella syndrome, neurofibromatosis, and tuberous sclerosis. Autism can also be present in genetic syndromes such as fragile X syndrome and phenylketonuria. Some research has shown that there may be an autism gene, or two genes working together. These genes are thought to be on the seventh and thirteenth chromosome.