What is Autism?
Autism is one of five different Pervasive Developmental Disorders that includes Asperger’s Disorder, Pervasive Developmental Disorder Not-Otherwise Specified (PDD-NOS), Childhood Disintigrative Disorder and Rett’s Syndrome. Childhood Disintigrative Disorder and Rett’s Syndrome are very rare (about 1 in 40,000). Autism, PDD-NOS and Asperger's collectively are often referred to as an Autism Spectrum Disorder.
When autism was first characterized by Leo Kanner in 1943, the prevalence was estimated at 1 in every 2,000 children. Today, one out of every 500 children are affected with autism. If all of the ASDs are included, the rates jump to one out of every 150 children.
Because autism has been the focus of considerable research and clinical attention, this summary will focus particularly on Autistic Disorder, although some generalizations can be reasonably made to the remaining ASDs.
Social Behavior
• In the young child with autism, the epicenter of social deficits are often thought of as abnormalities in “social attention” behaviors. Defects in social attention can take the form of reduced eye contact, reduced showing of objects, reduced pointing, reduced following a speakers line of gaze and the like. In brief, the child with autism often does not make frequent attempts to join the social emotional world of others and, conversely, to draw others into their world.
• As the child matures, other social abnormalities become apparent, such as more pronounced abnormalities in eye contact, reductions in reciprocal social interaction, and difficulties in identifying and interpreting the emotions of others. Finally, difficulties in the ability to take the mental perspective of another person (a.k.a. “Theory of Mind”) is also common in autism and may emerge as the direct result of difficulties with early social attention.
• While the image of an autistic child sitting alone in a corner and swaying his body up and back is sometimes valid, it does not represent the child as a whole. In fact, children with autism can and do form strong social attachments to their caregivers. They smile and laugh and can experience great joy.
Language
• Approximately 50% of all individuals with autism fail to develop functional speech, and for those that do, language is characterized by several abnormalities including pronoun reversals (e.g., saying "he went to the market instead of "I" went to the market) use of neologisms (nonsensical or made up words), stereotyped or rigid speech and abnormalities in intonation.
• The speech of autistic individuals is also characterized by echolalia, which is the repetition of words either right after someone speaks them or after a delay of hours, days, or even months. For example, an autistic individual may repeat the phrase “how old are you?” hundreds of times in a single day, after hearing the phrase only once.
Cognition
• Seventy five percent of autistic individuals also suffer from cognitive difficulties, ranging from mild to severe. In fact, approximately 75% of people with autism are also mentally retarded.
•Although it is difficult to disentangle secondary effects of early social and language impairment from mental retardation per se, some scientists believe that deficits in higher order memory abilities, conceptual reasoning (e.g., categorization skills), executive function (e.g., switching between two or more mental sets), and auditory information processing may exist as important features of this disorder.
Restricted and Repetitive Interests
•Individuals with autism commonly display restricted, repetitive and stereotyped patterns of interests, and activities. This general category of behavior manifests itself in many ways such as an inflexible adherence to specific routines, stereotyped and repetitive motor mannerisms (e.g., hand-flapping) or a preoccupation with an object or part of an object.
•In general, autistic individuals display a significantly reduced interest in their environment, instead, focusing their attention on one specific aspect of the environment (e.g., a lamp) or obsessive idea (e.g., amassing facts about cars). Further, individuals with autism may insist on sameness and show distress over trivial changes in their environment (e.g., movement of a piece of furniture).
• Restricted and repetitive environmental interests likely interfere with learning and may have significant developmental implications for the autistic child because he or she may miss many learning opportunities that fall outside their scope of interest. Combined with attention deficits described above, the autistic child is ill prepared to learn from their environment.
