What Are the Symptoms of Autism?

The core symptoms of autism are:

social communication challenges and
restricted, repetitive behaviors.

Symptoms of autism may:

begin in early childhood (though they may go unrecognized)
persist and
interfere with daily living.

Specialized healthcare providers diagnose autism using a checklist of criteria in the two categories above. They also assess autism symptom severity. Autism’s severity scale reflects how much support a person needs for daily function.

Many people with autism have sensory issues. These typically involve over- or under-sensitivities to sounds, lights, touch, tastes, smells, pain and other stimuli.

Autism is also associated with high rates of certain physical and mental health conditions.

Social communication challenges

Children and adults with autism have difficulty with verbal and non-verbal communication. For example, they may not understand or appropriately use:

Spoken language (around a third of people with autism are nonverbal)
Gestures
Eye contact
Facial expressions
Tone of voice
Expressions not meant to be taken literally

Additional social challenges can include difficulty with:

Recognizing emotions and intentions in others
Recognizing one’s own emotions
Expressing emotions
Seeking emotional comfort from others
Feeling overwhelmed in social situations
Taking turns in conversation
Gauging personal space (appropriate distance between people)

Restricted and repetitive behaviors

Restricted and repetitive behaviors vary greatly across the autism spectrum. They can include:

Repetitive body movements (e.g. rocking, flapping, spinning, running back and forth)
Repetitive motions with objects (e.g. spinning wheels, shaking sticks, flipping levers)
Staring at lights or spinning objects
Ritualistic behaviors (e.g. lining up objects, repeatedly touching objects in a set order)
Narrow or extreme interests in specific topics
Need for unvarying routine/resistance to change (e.g. same daily schedule, meal menu, clothes, route to school)