Autism Spectrum Contains a Range of Disorders
Autism spectrum disorders range from a severe form, called autistic disorder, to a milder form, Asperger syndrome. If a child has symptoms of either, but does not meet the specific criteria, the diagnosis is called pervasive developmental disorder not otherwise specified (PDD-NOS).
All children with autism spectrum disorders demonstrate deficits in social interaction and in verbal and nonverbal communication; they also display repetitive behaviors or interests and will often have unusual responses to sensory experiences, such as certain sounds. These symptoms run the gamut from mild to severe.
SOURCE: National Institute of Mental Health