Autism is a lifelong, neurobiological condition that significantly affects how a person perceives the world, interacts with other people, and communicates. There is no known single, specific cause of autism. Furthermore, no known psychological factors in the development of the child have been shown to cause autism.
Autism is a spectrum disorder .
This means that the symptoms and characteristics of autism can present themselves in a wide variety of combinations, from mild to severe. Although autism is defined by a certain set of behaviors, children and adults can exhibit any combination of the behaviors in any degree of severity. Some children with autism spectrum disorders demonstrate a delay early in life while others appear to develop typically until the age of 24-30 months, when parents may notice delays or regression in language, play, or social interaction. Autism Checklist Individuals with autism usually exhibit at least half of the traits listed below. These symptoms can range from mild to severe and vary in intensity from symptom to symptom.