What is autism spectrum disorder (ASD), previously called autism and pervasive developmental disorders?

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by the following:

  • Difficulties in social communication differences, including verbal and nonverbal communication.
  • Deficits in social interactions.
  • Restricted, repetitive patterns of behavior, interests or activities and sensory problems

Many of those with ASD can have delayed or absence of language development, intellectual disabilities, poor motor coordination and attention weaknesses.

What is the difference between autism and autism spectrum disorder (ASD)?

The term autism was changed to autism spectrum disorder in 2013 by the American Psychiatric Association. ASD is now an umbrella term that covers the following conditions:

  • Autistic disorder.
  • Pervasive developmental disorder — not otherwise specified (PDD-NOS).
  • Asperger syndrome.

People with ASD have trouble with social interactions and with interpreting and using non-verbal and verbal communication in social contexts. Individuals with ASD may also have the following difficulties:

  • Inflexible interests.
  • Insistence on sameness in environment or routine.
  • Repetitive motor and sensory behaviors, like flapping arms or rocking.
  • Increased or decreased reactions to sensory stimuli.

How well someone with ASD can function in day-to-day life depends on the severity of their symptoms. Given that autism varies widely in severity and everyday impairment, the symptoms of some people aren’t always easily recognized.

When might you begin to wonder if your child has autism spectrum disorder (ASD)?

While ASD is believed to be a disorder of very early brain development, the behavioral signs of autism characteristics surface between age 1 and ½ years of age and 3 years of age.

How common is autism spectrum disorder (ASD)?

Based on most recent CDC report, ASD is estimated to affect about 1 in 54 children, with boys being more likely to have ASD than girls. There were more than 5 million adults in the US, or 2.21% of the population, with ASD as of 2017. Government statistics suggest that the prevalence of ASD (how common it is) has risen 10% to 17% in recent years.

What causes autism spectrum disorder (ASD)?

There is no clear-cut cause of ASD. Some causes that are supported by research include genetic and some environmental factors. Specific genetic causes can only be identified in 10% to 20% of cases. These cases include specific genetic syndromes associated with ASD and rare changes in the genetic code.

Risk factors include older parental age, low birth weight, prematurity and maternal use of valproic acid or thalidomide during pregnancy, among others. This field of study is an active one for reasearch.

Are siblings at greater risk for autism spectrum disorder (ASD)?

The truth is that genetics do play a role in autism. When one child is diagnosed with ASD, the next child to come along has about a 20% greater risk of developing autism than normal. When the first two children in a family have both been diagnosed with ASD, the third child has about a 32% greater risk of developing ASD.

Do vaccines cause autism (ASD)?

Many scientifically-sound studies have proven that vaccines do not cause autism. When children suddenly show symptoms of ASD, some parents mistakenly blame a recent vaccination. No reliable study has found any proven link between childhood vaccination and autism.

What are the signs of autism spectrum disorder (ASD)?

Signs of ASD range from mild to severely disabling, and every person is different. The following signs are considered to be red flags that indicate your young child may be at risk for autism. If your child shows any of the following signs, please get in touch with your child’s healthcare provider to discuss a referral for an autism evaluation.

The signs include the following:

  • Your child doesn’t respond to their name being called at all or responds inconsistently.
  • Your child doesn’t smile widely or make warm, joyful expressions by the age of 6 months.
  • Your child doesn’t engage in smiling, making sounds and making faces with you or other people by the age of 9 months.
  • Your child doesn’t babble by 12 months.
  • No back-and-forth gestures such as showing, pointing, reaching or waving by 12 months.
  • No words by 16 months.
  • No meaningful, two-word phrases (not including imitating or repeating) by 24 months.
  • Any loss of speech, babbling or social skills at any age.

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