What is autism?
Autism is a type of pervasive developmental disorder (PDD). It interferes with a person's ability to communicate with and relate to others. Autism is a lifelong condition that results in some degree of social isolation.
Autism affects how a person perceives and processes sensory information. Signs of autism almost always develop before a child is 3 years old, although the condition is frequently not diagnosed until later. Typically, parents first become concerned when they notice their toddler does not respond or interact like other children of the same age. Toddlers with autism do not usually babble or talk normally, and may seem to have hearing problems.
The severity of autism varies. Some individuals need assistance in almost all aspects of their daily lives, while others are able to function at a very high level and can even attend school in a regular classroom. Although it is difficult to determine, studies show that below-normal intelligence occurs in about 70% of autistic children In addition, the social functioning of autistic children is less than what is expected for their intelligence quotient (IQ) levels.


What causes autism?
Most research suggests that people with autism have irregular brain structures. More study is needed to determine the cause of these irregularities, but current research indicates they are inherited. Parents who have had one child with autism are more likely than other couples to have a second child with autism.


What are the symptoms of autism?
All people with autism have difficulty with social interactions and relationships. Parents often describe their child with autism as preferring to play alone and making little eye contact with other people. Other symptoms of autism include:
Difficulties with verbal and nonverbal communication. Language development in children with autism is almost always delayed.
Limited, repetitive, and overused (stereotyped) patterns of behavior, interests, and play. Many typical behaviors-such as repetitive body rocking, unusual attachments to objects, and holding fast to routines and rituals-are driven by the need for sameness and resistance to change.
There is no standard or "typical" person with autism. Although autism is defined by the above characteristics, people with autism can have many different combinations of behaviors in mild to severe forms.
Many people with autism also have other conditions, such as below-normal intelligence or mood problems. Teenagers with autism often develop depression, especially if they have average or above-average intelligence. In addition, about 1/3 of children with autism develop a seizure disorder such as epilepsy by their teen years.