Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a developmental disorder that affects learning, language, and/or behavior, beginning in childhood.

The autism “spectrum” means there are many differences in the number and types of symptoms, seriousness, age of onset, and levels of functioning from person to person.

Some people on the autism spectrum display very few symptoms, while others may display many symptoms. Symptoms may include:

  • Trouble with social communication and social interaction.
  • Restricted patterns of behavior, interests, or activities.
  • Sensory processing difficulties.
  • Anxiety.
  • Hyperactivity.
  • Behavioral challenges (physical aggression, verbal aggression, property destruction, tantrums, and/or self-injurious behaviors).

Children diagnosed with ASD typically display symptoms at an early age. Therefore, when parents have any concerns about their child’s development, early evaluation and diagnosis are strongly recommended.

Early symptoms of autism spectrum disorder may include:

  • Disconnection to others.
  • Lack of interest in interacting with others.
  • Delayed development of language.

See the ASD Handbook for common “red flags.”


Individuals who meet the diagnostic criteria for ASD receive a diagnosis of autism spectrum disorder level 1, level 2, or level 3.

ASD Level 1

The person:

  • Needs support.
  • Typically speaks in complete sentences but has difficulties with reciprocal conversations.
  • Shows some inflexibility in routine.
  • Has difficulties transitioning from one environment/activity to another environment/activity.

ASD Level 3

The person:

  • Needs very substantial support.
  • Shows more severe delays in communication and social interactions than those diagnosed with level 1 or level 2.
  • Has a difficult time functioning in daily life.
  • Engages in high rates of repetitive behaviors.

ASD Level 3

The person:

  • Needs very substantial support.
  • Shows more severe delays in communication and social interactions than those diagnosed with level 1 or level 2.
  • Has a difficult time functioning in daily life.
  • Engages in high rates of repetitive behaviors.

We have a toll-free Autism Support Line that you can call if you need information about autism services for your child: 1-866-415-1708.

For more information about ASD and available services, view the ASD Handbook.