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What are the types of autism?

It’s a common belief in the neurotypical community that there are “types” of autism. However, doctors diagnose individuals with Autism Spectrum Disorder (ASD), a diagnosis encompassing several disorders ranging in severity. That was a fairly recent change; the sole ASD diagnosis came about in 2013.

Until then, individuals were diagnosed with one of four disorders that many assumed were the 4 “types of autism”: Autistic Disorder, Asperger Disorder, Childhood Disintegrative Disorder (CDD), or Pervasive Developmental Disorder – Not Otherwise Specified (PDD-NOS).

That all changed when the American Psychiatric Association (APA) updated its diagnostic criteria in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). The APA explained that Autistic Disorder, Asperger Syndrome, Childhood Disintegrative Disorder, and PDD-NOS would be best thought of as a single disorder covering a wide spectrum.

As researchers discover more about ASD, our understanding of the disorder also changes. Keep reading to learn how far this diagnosis has come and how you can get treatment for your child.


Former Diagnoses

When a person asks about the 4 “types” of autism, they most likely want to know more about the disorders listed above. These are no longer active diagnoses, but it’s important to understand the role they played in the development of an overarching ASD diagnosis. 


Autistic Disorder

Autism was first listed as a diagnosis in 1980. The DSM-III defined three essential features of the disorder, all of which had to be present within 30 months of life:

  • Lack of interest in people and socialization
  • Severe impairments in the areas of communication and language. If speech was present, peculiar speech patterns (echolalia, etc.)
  • Bizarre responses to the environment (resistance to change, peculiar interest in objects)

Pervasive Developmental Disorder – Not Otherwise Specified (PDD-NOS)

The DSM-III was revised in 1987 and featured several significant changes. One of these was PDD-NOS, an added diagnosis at the mild end of the autism spectrum. 

No one used the word “spectrum” at this point, but the addition of PDD-NOS demonstrates a shift in experts’ understanding of autism – a shift that would continue in subsequent years.

PDD-NOS diagnoses were applied to individuals on the autism spectrum who did not meet certain diagnostic criteria for autistic disorder or Asperger disorder.

For example, an individual may have had difficulty speaking with others but did not demonstrate restricted, repetitive behaviors, one of the main criteria of ASD.

Asperger’s Disorder

The same DSM update that first featured “spectrum” also introduced Asperger’s as a diagnosis. This was the DSM-IV, released in 1994 and revised in 2000.

Asperger’s was considered a high-functioning form of autism, with most individuals possessing average or above-average intelligence. Although these individuals were perhaps more independent than their peers with AD or PDD-NOS, they still had challenges, especially in areas of socializing, emotional regulation, and repetitive interests.

Childhood Disintegrative Disorder (CDD)

Childhood Disintegrative Disorder was first included in the DSM-IV in 1994.

CDD is a late-onset, severe regressive form of ASD. Children with CDD experience behavior dysregulation (fear, anxiety, crying) lasting from a few weeks to a few months, which is followed by developmental plateau and regression.

In this sense, “regression” means a loss of skills, including social, emotional, and language skills. 

Children with CDD are more severely impaired than children with ASD, typically having lower IQs and a higher risk of epilepsy.

Like Asperger’s, PDD-NOS, and Autistic Disorder, CDD is no longer a viable diagnosis.


What Former Diagnoses Have in Common

The disorders mentioned above are no longer applicable diagnoses, but they did play an important role in creating the diagnosis of ASD. 

Each was folded under the ASD umbrella because they shared many symptoms within the same developmental areas: language, socialization, emotional regulation, and independence.

Before revising in 2013, the DSM classified autism symptoms into three categories, all of which had to be met to receive a diagnosis of Autism Disorder, PDD-NOS, Asperger’s, or CDD:

  • Social impairment
  • Language/communication impairment, and 
  • Restricted and repetitive behaviors.


Now, children must exhibit the following to be diagnosed with ASD:

  • Persistent deficits in social communication and interaction, and 
  • Restricted and repetitive behaviors, a symptom of which is sensory issues like hyper- or hypo-reactivity to external stimuli (lights, sounds, etc.)

Treatment for Autism Spectrum Disorder

In 2013, the American Psychiatric Association updated its diagnostic criteria, characterizing autism as an all-inclusive disorder on a  spectrum instead of several different diagnoses.

As you can tell, the former and current diagnostic criteria for autism are pretty similar, but there are some slight differences in how the disorder is diagnosed and treated. At Therapeutic Pathways, we follow the most recent and scientifically-validated methods for accepting and treating clients.

We do not diagnose autism, but we do provide therapeutic services for children, teenagers, and adults. Once your child has a diagnosis, you can seek treatment at any of our California centers. 

For more information, call Therapeutic Pathways at (209) 422-3280.