Autism Facts

General Definition

An autism spectrum disorder is a developmental disorder that affects many aspects of a child’s functioning. The disorder is characterized by delays in communication skills, difficulty with social interaction and imaginative play, and behavioral symptoms involving repetitive behaviors and/or a limited range of interest in activities.

Autism is referred to as a spectrum disorder due to the variety of characteristics and the range of severity that is unique to each child. Even though children diagnosed with an autism spectrum disorder share a common set of behavioral characteristics, no two individuals will be alike. Each child is unique and has a varying set of strengths and challenges.

Socially, some children may relate comfortably with family members and show social interest while others may be socially withdrawn in almost all situations. Some children are able to use complex language, while others require the use of pictures or signs to communicate. Some children may have excellent learning skills while others may be behind in their development. Children with autism spectrum disorders may also exhibit different symptoms over time or from one situation to the next.

Autism Facts & Stats (PDF)

Definitions of the different spectrum disorders

  • Autistic Disorder: Children who meet full criteria for the disorder according to the Diagnostic and Statistical Manual of Psychiatry (DSM-IV). Children in this group vary quite a bit; however, they each have characteristics in areas of communication, social interaction and repetitive behaviors which are severe enough to meet criteria for the disorder.
  • Pervasive Developmental Disorder – Not Otherwise Specified (PDD-NOS): Children with this diagnosis typically have many features of autism, such as severe and pervasive difficulties in social and communication behaviors, but do not meet the full criteria for Autistic Disorder. They may not have symptoms in each of the three categories or their symptoms may be more mild.
  • Asperger’s Syndrome: This is diagnosed in school-aged children who have social and behavioral symptoms of autism without the language delay. Measured intelligence is in the average to above-average range. Frequently these children show an almost obsessive interest that is unusual in intensity and focus.
  • Additional Disorders: Autism, Asperger’s Syndrome and other Pervasive Developmental Disorders can occur by themselves or in combination with other disabilities. Children usually have symptoms of Attention Deficit Hyperactivity Disorder (ADHD), which is part of the Pervasive Developmental Disorder. They may also experience learning disabilities, anxiety disorders, obsessive-compulsive disorders, epilepsy or mental retardation. It is estimated that approximately 70 percent of those diagnosed with an autism spectrum disorder are also diagnosed with mental retardation ranging from mild to severe.


According to the Center for Disease Control (CDC), the number of children with an autism spectrum disorder is estimated to be one in 88. It is five times more likely to occur in males than in females for unknown reasons.


There is no single known cause for autism. There are many theories about potential causes, and it appears that multiple factors are involved. Autistic spectrum disorders are physical disorders of the brain that are neurologically-based and are not emotional disorders. Parents do not cause autism. The exact cause remains unclear, as we still do not understand how autism affects the structure of the brain, brain function or brain chemistry. There is some evidence of a genetic component, as studies have shown that if a family has one child with autism, they are at some increased risk of having another child with autism. Autism has also been associated with a wide range of pre-, peri- and postnatal difficulties.

Parental Response to the Diagnosis

Receiving a diagnosis may alter the dreams you have for your child. Remember to maintain your determination, obtain the support you need and don’t lose hope. There are few guidelines for predicting outcomes for children with an autism spectrum disorder. Research into causes and interventions is currently growing at an amazing rate; much has been learned in the last 10 years. More adults with autism spectrum disorders are describing their experiences and providing us with incredible insight. Certainly, there are successes that have been accomplished with hard work, creativity and perseverance from individuals themselves, their family members, and the professionals and community members who are involved.

Family support is very important. Various support groups are available through the local Autism Society, EFRC and other private agencies. Please see the Autism Resource Guide for more information.