Autism Spectrum Disorders: An Overview

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Definitions:

DSM-IV-TR: Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition - Text Revision.
A manual published in 2000 that outlines the specific characteristics required for the classification of all psychiatric disorders.

PDD: Pervasive Developmental Disorder.
The clinical or medical term for a constellation of 5 diagnoses listed in the DSM-IV-TR with core difficulties in social communication.

ASD: Autism Spectrum Disorders
An increasingly used term for three most common PDD diagnoses (Autistic Disorder, Apserger’s Disorder, and Pervasive Developmental Disorder - Not Otherwise Specified [PDD-NOS]).

Facts

There are five disorder categories under the label Pervasive Developmental Disorders:

  1. Autistic Disorder*
  2. Asperger's Disorder*
  3. Pervasive Developmental Disorder*
  4. Childhood Disintegrative Disorder
  5. Rett's Disorder

* Characteristic symptoms present prior to the age of three.

Individuals with Autistic Disorder exhibit challenges and meet criteria in 3 main areas:

  1. Social Interaction - e.g., limited eye contact and gestures, difficulty making friends, difficulty understanding common social rules
  2. Communication - e.g., delay in or lack of spoken language, unusual use of language (e.g., not conversant), limited or no creative play
  3. Repetitive/Restricted Interests - e.g., excessive interest in unusual objects, limited use of objects and interests or intense interest in limited topic areas; repetitive motor mannerisms; excessive need for routine

Individuals with Asperger’s Disorder exhibit challenges and meet criteria in 2 main areas::

  1. Social Interaction
  2. Repetitive/Restricted Interests
Additionally, individuals have no significant delay in language or cognitive skills though they often have unusual and pressured language and have difficulty maintaining conversations outside of their area of interest

Individuals with PDD-NOS exhibit challenges across all three areas above.

Individuals with Rett’s Disorder develop appropriately for the first 5 months and then experience:

  1. Loss of hand skills and development of classic repetitive hand movements (i.e., hand wringing)
  2. Loss of social interaction at onset of disorder
  3. Communication difficulties (both with expression and understanding of language)

Individuals with Childhood Disintegrative Disorder develop appropriately for at least 2 years and then experience:

  1. Loss of skills (communication, bladder control, play skills, motor skills)
  2. Abnormalities in at least two of the following three areas:
    1. Social Interaction
    2. Communication
    3. Repetitive/Restricted Interests


Diagnosing PDD/ASD:

  1. Done by one of a few types of professionals:
    • Clinical Psychologists
    • Psychiatrists
    • Neurologists
    • Developmental Pediatricians
  2. A variety of methods are used
    • Behavioral observations
    • Standardized testing
    • Clinical impressions focused on DSM-IV-TR criteria
    • Historical records and reports
    • Clinical Interview

Recommended Actions

When working with individuals with PDDs, try to capitalize on their strengths:

  • Present information visually, whenever possible
  • Establish consistent routines to help individuals know what to expect
  • Break complex routines into simple steps when teaching these routines


References

American Psychiatric Association (2000). Diagnostic and statistical manual of mental disorders (4th ed. – text revision): DSM-IV-TR. Washington, DC: Author.