Autism Spectrum Disorder - Pervasive Development Disorders and Their Relationship to Autism

All developmental disorders can be classified as either Pervasive or specific. Autism Spectrum Disorder (ASD) is classified as a pervasive disorder. A Pervasive Development Disorder (PPD) involves behavior disorders and psychological development disorders that alter the mental and physical functions of the person. Most people with PPD experience disabilities that affect a variety of functions.

A Specific Development Disorder (SDD) affects only a specific area of functioning for the individual. It can be Dyslexia so the person has a hard time reading and writing, Dyspraxia that affects movements, Discalcula that affects math equations and processes, or Dysgraphia that prevents the person from learning to read or write at all. The main difference between PPD and SDD is the number of areas that are affected, not the severity of them.

Autism falls into the category of PDD, so individuals with Autism display disabilities in a variety of areas that relate to social skills, communication, and behaviors. Each person with Autism experiences a variety of concerns at the level of them varies in degree of severity. The Autism Spectrum is used to help measure the particular level of Autism for each person.

Low Functioning Autism relates to the most severe cases of it. The individuals in this category have many disabilities and they are severe in nature. This generally involves the person having a very low IQ. High Functioning Autism relates to those who have only a few areas of impairment and a high IQ. They often excel in a given area of talent that can't be explained. Individuals who have been diagnosed with Asperger's Syndrome display a high level of functioning as well.

A common mistake is to classify PDD and Autism as the same thing. While they are related in some of their characteristics they are to distinct areas. Rett's Syndrome and Childhood Disintegrative Disorder are in the Autism Spectrum classification. This is because they show Autistic behaviors. Yet the overall diagnosis is different because of the other parts of the diagnosis that don't parallel Autism.