Understanding Autism Spectrum Disorders

In this article:
Origins of Autism Criteria & Current Standards
Diagnosis Considerations
Autistic Disorder
Asperger's Syndrome
PDD-NOS
Childhood Disintegrative Disorder
Rett's Disorder
Fragile X Syndrome
More Autism Resources

Experts like to point out that no two children with autism are quite alike. While that lack of clarity can be frustrating for parents, it demonstrates that researchers and doctors continue to refine their understanding of autism. Here is brief description of the places on the autism spectrum.

There is more than one type of autism. Autism is called a "spectrum disorder" to reflect the broad set of characteristics that doctors use to describe those who in general display a lack of ability to communicate and interact with others when compared to typically developing children.

It's common to hear autism experts say that no two children who receive the diagnosis are exactly alike. One person with autism may not be able to talk, while another will talk a great deal, nonstop, about subjects that interest him intensely. Some people with autism display very high levels of intelligence, while others may have mental retardation.

This lack of black-and-white clarity can be frustrating for parents and family members new to autism who seek to understand what's going on with their very young child and try to assess how this diagnosis will influence not just their child, but everyone in the family. (See What to Do When You Get an Autism Diagnosis for more on family transitions.)

Origins of Autism Criteria & Current Standards

Most of the time, doctors and child development experts diagnose autism spectrum disorders based on observations and interviews that uncover both what is happening and what is NOT happening with a young child's ability to communicate and interact with others.

These criteria are codified in a 2000 tome for doctors called the DSM-IV-TR, for Diagnostic and Statistical Manual of Mental Disorders (Fourth edition, text revision) published by the American Psychiatric Association. (A preview of this book is available via Google Books; search for "autism disorder." Additionally, the National Center on Birth Defects and Developmental Disabilities have posted the diagnostic criteria for autism here.) These criteria published in 2000 are due for a revision in 2011, according to the advocacy group, Autism Speaks.

One thing is clear: The medical community's work in understanding autism is still in its early stages. It was just in 1943 that Leo Kanner published the first medical research paper on autism (read it here), based on observations of children who were his patients. In the 1950s and 1960s, a famous psychologist, Bruno Bettelheim, popularized the mistaken and harmful belief that "refrigerator mothers," women who didn't love their babies enough, were to blame for autism.

We've come a long way since then, and in 2007 the American Academy of Pediatrics (AAP) decided to make autism screening a major priority for primary care doctors to conduct at annual well-child checkups. With the rising prevalence of cases has come increased awareness and a sense of urgency to identify what's going on with our kids.

Diagnosis Considerations

Doctors use diagnostic labels to describe different types of autism. These labels all say autism because they share two common traits—impaired social interaction and communication skills—but the use of a spectrum of disorders to analyze these conditions shows that that there's great variability among different types of people who have these common traits.

As you read the following descriptions of different autism spectrum disorders, keep a few things in mind:

The diagnoses can overlap.
Some people's diagnoses can change over time as their demonstrated abilities and behaviors change.
Most importantly, there are a growing number of resources available to help parents understand more about autism and what to do when a child gets a diagnosis .