What Does the Diagnosis "Autism" Mean?

There are 5 Pervasive Developmental Disorders –

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

At the present time, there are no genetic, neurological or other physical markers that can be used to distinguish a person with autism from persons with similar behavioral characteristics. Instead, the diagnosis of autism is applied to persons who meet specified behavioral criteria. The problems should be evident before age 3.

Read more about the diagnosis and the degree to which it influences behavior analytic treatment.

Autistic Disorder

In summary, the behavioral characteristics associated with autism are:

1. significant difficulties with social interactions – does not pay attention to other people; does not play with other children; does not reciprocate
2. significant difficulties in verbal and nonverbal communication – grabs what is wanted or leads to get what is wanted; copies or parrots words (echolalia); if has words, does not converse
3. significant difficulties in the development of play – uses only parts of toys; lines up or stacks objects; no imaginative play
4. highly restricted, repetitive and stereotyped patterns of behavior and interests. May talk continuously about one topic or repeat the same questions; may spin and stare at objects; may flap fingers or pieces of string; mouth or hit self
5. highly resistant to even slight changes in routines

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Rett's Disorder

differs from autism primarily in that it is associated with loss of previously acquired hand skills between ages 5 months and 30 months and onset of severe or profound mental retardation. Motor skills are replaced with repetitive movements of the hands.

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Childhood Disintegrative Disorder

is diagnosed when a child shows significant losses in social behavior, language, play and adaptive behavior after development was apparently normal for at least the first 2 years and before 10 years of age.

Both Rett's Disorder and Childhood Disintegrative Disorder appear to be very rare. Little behavioral research has been conducted with persons with these diagnoses.

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Asperger's Disorder

differs from Autistic Disorder in that impairment is primarily within the domain of social interactions. Development of other adaptive behavior, cognition, and language are not significantly delayed. Repetitive patterns of behavior or rituals must also be present. This disorder tends to be recognized and diagnosed later, usually after 3 years of age. Whether this is because the characteristics are less noticeable or the disorder has a later age of onset is not known.

Another matter of controversy is whether Asperger's Disorder is a milder form of Autistic Disorder or a distinct disorder.

Although Asperger described this syndrome in 1945, only one year after Kanner's original article, the diagnosis was not included in DSM prior to the 1994 Edition.

Presently there is no behavioral research devoted specifically to persons with Asperger's Disorder. The most relevant work to date in the behavioral literature would be studies that included persons with autism characterized as "high functioning" or persons referred specifically because of problems in social interaction, or labeled "with autistic features" or PDD NOS.

For more information, go to the Family Village web site on this topic.

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Pervasive Developmental Disorder Not Otherwise Specified ("PDD NOS")

This label is used when severe impairments in reciprocal social interaction or communication skills are present or when stereotyped and restricted activities and interests are exhibited, but the criteria listed above for disorders in the spectrum are not met completely. It is a borderline category and sometimes referred to as "atypical autism." The DSM IV diagnostic categories are reproduced in English and French in the Quebec Society for Autism page.

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Diagnosis and Applied Behavior Analysis

Behavioral investigations and therapeutic programs have developed independently of issues and disputes about diagnosis. This is so because behavior analysis starts with a detailed investigation of the individual. s current strengths, needs, and life circumstances. ABA uses basic principles of learning and behavioral development that cut across diagnoses.

Prior to 1980, autism was classified as a childhood psychosis or a variant of childhood schizophrenia. Thus, early work about autism will be found under these labels. Readers will have to look at the descriptions of the participants in earlier work to determine if they would have been classed as autistic by current criteria .

Because many persons diagnosed as autistic also meet the criteria for the diagnosis, mental retardation, the mental retardation literature is also a good source of information about programs for behavior management, education, community integration and so on.

Although not required by behavior analysts for planning and implementing intervention programs, a diagnosis based on complete neurophysiological and psychological examinations is essential .

• to learn about causes and etiology
• to learn about signs that will permit earlier detection of children at risk for autism
• to obtain educational and other special benefits

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