What is Autism?

Autism is a complex developmental disability that typically appears during the first three years of life and is the result of a neurological disorder that affects the normal functioning of the brain, impacting development in the areas of social interaction and communication skills. Both children and adults with autism typically show difficulties in verbal and non-verbal communication, social interactions, and leisure or play activities.

The term “spectrum” is crucial to understanding autism, because of the wide range of intensity, symptoms and behaviors, types of disorders, and as always, considerable individual variation.

Children with autism spectrum disorders may be non-verbal and asocial, as in the case of many with “classic” autism, or Autistic Disorder. On the other end of the spectrum are children with a high-functioning form of autism characterized by idiosyncratic social skills and play, such as Asperger Syndrome. In the Diagnostic and Statistical Manual (DSM-IV), these diagnostic categories are outlined under the heading of “Pervasive Developmental Disorders (PDDs).”

In the DSM-IV, these disorders are defined by deficits in three core areas: social skills, communication, and behaviors and/or interests. Types of autism spectrum disorders, or PDDs, include:

  • Autistic Disorder
  • Asperger Syndrome
  • Childhood Disintegrative Disorder
  • Rett Syndrome
  • Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS)

More information about the diagnostic categories of autism may be found at the Autism Society of America’s Web site.

Prevalence of Autism

Autism is the most common of the Pervasive Developmental Disorders, affecting an estimated 1 in 150 births (Centers for Disease Control Prevention, 2007). Roughly translated, this means as many as 1.5 million Americans today are believed to have some form of autism. And this number is on the rise.

Based on statistics from the U.S. Department of Education and other governmental agencies, autism is growing at a startling rate of 10-17 percent per year. At this rate, the ASA estimates that the prevalence of autism could reach 4 million Americans in the next decade.

Autism knows no racial, ethnic, social boundaries, family income, lifestyle, or educational levels and can affect any family, and any child.

And although the overall incidence of autism is consistent around the globe, it is four times more prevalent in boys than in girls.