The child may show an insensitivity to pain and lack of responsiveness to cold or heat, or may overreact to any of these. Uneven patterns of intellectual functioning - The majority of people with autism have varying degrees of mental retardation. Marked restriction of activity and interests - A person with autism may perform repetitive body movements, such as hand flicking, twisting, rocking, or spinning. This person may also display repetition by following the same schedule everyday, same route, same order of dressing, etc. If changes occur in these routines, the child may become upset.
Autism is a brain disorder, present from birth.
What causes autism in specific cases is still unknown. It is known that autism IS NOT caused by the psychological environment a child grows up in. Some research suggests a physical problem affecting parts of the brain that process language and information coming in from the senses. Other research points to an imbalance of some brain chemicals. Genetic factors are often involved.