Skip to content

Loading...

Signs & Characteristics

Signs & Characteristics

Autism may involve differences in social communication, gestures, play, repetitive movements or speech, routines, focused interests, and sensory experiences. No single characteristic confirms autism. Discuss concerns or loss of previously acquired skills with a healthcare professional.

Based on NIMH · CDC · All sources · Checked November 3, 2026

9 monthsCDC lists not responding to one’s name by this age as one exampleCDC · examples, not a checklist
12 monthsusing few or no gestures, such as waving goodbye, is another exampleCDC · examples, not a checklist
18 monthsnot pointing to show something interesting is another exampleCDC · examples, not a checklist

Areas families may notice

Communication

Back-and-forth conversation, tone of voice, gestures, and responding to one’s name.

Play and interaction

Sharing interest or enjoyment, pretend play, and joining other children.

Routines and interests

Strong, lasting interests and feeling upset by small changes in routine.

Sensory experiences

Being more or less sensitive to light, sound, clothing, taste, or temperature.

Learning and movement

Different ways of learning, moving, or paying attention.

Examples of experiences — not a way to diagnose your child. Every autistic person is different, and people who are not autistic may share some of these. Sources: NIMH, CDC.

Social communication and interaction

Examples may include:

  • Making little or inconsistent eye contact
  • Infrequently sharing interest, emotion, or enjoyment — including rarely pointing at or showing things to others
  • Not responding, or being slow to respond, to one’s name
  • Having difficulties with the back and forth of conversation
  • Facial expressions, movements, and gestures that do not match what is being said
  • Trouble understanding another person’s point of view
  • Difficulties sharing in imaginative play or making friends

Restricted or repetitive behaviors and interests

Examples may include:

  • Repeating words or phrases (called echolalia)
  • A lasting, intense interest in specific topics, such as numbers, details, or facts
  • Overly focused interests, such as in moving objects or parts of objects
  • Becoming upset by slight changes in a routine and having difficulty with transitions

Sensory differences

Autistic people often are more sensitive or less sensitive than other people to sensory input, such as light, sound, clothing, or temperature. Some also experience sleep problems and irritability.

Other characteristics

CDC notes that many autistic people also have related characteristics, such as delays in language, movement, or learning; differences in attention; unusual eating or sleeping habits; digestive issues; anxiety; or seizures. A child does not need to have all — or any — of these examples to be autistic, and children who are not autistic can show some of them.

No single characteristic confirms autism. If you notice something that concerns you, or your child loses skills they once had, talk with your child’s doctor. How to get an evaluation.
Sources

Adapted from the National Institute of Mental Health, “Autism Spectrum Disorder,” revised 2025. Our website’s presentation does not imply NIMH endorsement.

Sources checked: November 3, 2026

This website provides general educational information. It does not diagnose autism or replace individualized medical, developmental, psychological, or educational advice. Screening is not diagnosis.

External listings do not imply affiliation, endorsement, or guaranteed services. Eligibility, availability, costs, and insurance coverage may change. Research summaries reflect evidence available at the time of review.