Autism is a developmental disability that is typically identified during the first three years of life. The result of a neurological disorder that affects the functioning of the brain, autism and its associated behaviors have been estimated to occur in as many as 1 in 88 individuals (source: Center for Disease Control and Prevention) and 1 in 54 boys. Individuals with characteristics of what is now called autism have been identified throughout the world in families of all racial, ethnic, and socio-economic backgrounds. However, the disorder was not formally recognized until the 1940’s, when Leo Kanner and Hans Asperger both independently coined the term autism.
Autism is one of five "autistic spectrum disorders" (ASD) described in the DSM-IV-TR under the heading of Pervasive Developmental Disorders (PDD). The other disorders on the spectrum include Asperger’s Syndrome, Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS), Childhood Disintegrative Disorder, and Rett’s Syndrome. All PDD’s overlap and portions of their clinical features are shared, however, they are distinct disorders and have specific diagnostic criteria.
Autism, the most commonly diagnosed PDD, interferes with the typical development of the brain in the areas that control all aspects of communication, social interaction, and sensory development. Individuals with autism may exhibit repetitive body movements such as hand flapping and rocking, show atypical responses to people and/or attachments to objects, exhibit difficulty with transitions and/or resistance to change. Autism is four times more common in males than females.
The symptoms and characteristics of autism may present themselves in a wide variety of combinations, ranging from mild to severe. Although autism is defined by the presence of a certain set of behaviors, individuals with autism may exhibit any combination of these behaviors, varying in degree of severity. Autism is known as a spectrum disorder. Therefore, two individuals with a diagnosis of autism may act very differently from one another.
While autism knows no racial, ethnic, or social boundaries, it does have some genetic component. Studies have shown that the prevalence of autism among siblings of individuals with autism is substantially higher than in the general population. Particularly in twin studies, if one identical twin has autism, it is likely that the other one will as well. Additionally, even when a history of autism is not found within a family, there may be a higher than expected prevalence of cognitive and social impairments within the family. These findings strengthen the hypothesis that some characteristics of autism may have a genetic basis.
As many as 1.77 million Americans today are believed to have some form of autism (source: ASA). Once thought to be a rare disorder, it is currently rated as the most common developmental disability-more common than Down’s Syndrome. Yet the majority of the public, including many professionals in the medical, educational, and vocational fields remain unaware of how autism affects individuals and how to implement the most effective interventions to assist these individuals in leading independent and productive lives.