Autism Definition

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Autism Definition

According to the Diagnostic and Statistical Manual of Mental Disorders IV( DSM-IV) and the National Institute of Neurological Disorders and Stroke (NINDS) autism is defined as " a range of complex neurodevelopment disorders characterized by social impairment, communication difficulties, and restricted, repetitive and stereotyped patterns of behaviors."

What exactly does this mean to the parents, teachers, caregivers, and the mental health professionals who work with children and adults who have been diagnosed with autism?

Signs and Symptoms

For most people autism is characterized by its symptoms and associated behaviors. Clinicians will look at two principle areas when determining who is autistic: 1) social interaction and communication; and 2) the presence of repetitive behaviors and/ or fixed interests. Usually, defects in these two areas are first detected by parents or caregivers and present themselves in early childhood.

Below are some of the signs, symptoms, and behaviors that may indicate an individual has ASD.

  • unresponsive to others (including close family members)
  • avoids or lacks eye contact
  • obsessive focus on one object or item to the exclusion of all others
  • difficulty interpreting feelings and emotions of others
  • appears to lack empathy
  • repetitive movements such as rocking, twirling, or head banging
  • failure to use personal pronouns like (I or me)
  • no babbling or pointing at objects by 6 mos.
  • no words by 16 mos., or two-word phrases by 2 years of age
  • loss of language or social skills (regression)
  • lining up toys or other objects rather than playing with them appropriately
  • no smiling
  • inability to make friends
  • inability to carry on sustained conversation or carries on long winded one-sided conversations
  • no imaginative or social play

Screening for autism is now carried out by doctors, mental health professionals, and even some parents using the Modified Checklist for Autism in Toddlers (M-CHAT) that was first developed by researchers in Great Britain. Although much has been learned and written about the signs and symptoms of autism, both the cause and possible cures still elude researchers.

Autism Definition: Other Autism Spectrum Disorders

Another little known fact about autism spectrum disorder (ASD) is that it encompasses other related conditions such as:

  • Asperger’s syndrome
  • Rett syndrome
  • Childhood Disintegrative Disorder
  • Pervasive Developmental Disorder(not otherwise specified) PDD-NOS

Each of these is a common childhood developmental disorder which affects communication and social interaction and may include repetitive stereotyped behavior. The most well-known of the four is probably Asperger’s syndrome, which is considered the mildest form of autism.

Autism Today

Much more is being learned about autism spectrum disorders. Researchers are uncovering more evidence that both the environment and genetics play pivotal roles in this neurodevelopmental condition. Because of this growing body of knowledge, the autism definition has become much more accurate. Informal terms such as high functioning, low functioning, mild, moderate, and severe are being added to help differentiate how affected an individual is by autism.

As its definition grows and expands, hopefully so will the ability to treat and possibly cure autism.


Autism Fact Sheet” National Institute of Neurological Disorders and Stroke, December 20, 2010

Diagnostic and Statistical Manual Of Mental Disorders IV, American Psychiatry Association,

“Autism Symptoms”, (referenced from Healthwise)1995-2010