Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders that affect the brain.

Children with autism learn, think, and experience the world differently than other children. They can face varying degrees of socialization, communication, and behavioral challenges.

ASD affects 1 in 59 children in the United States, estimates the Centers for Disease Control and Prevention.

Some children with autism don’t need much support, while others will need daily support throughout their lifetime.

Signs of autism in 4-year-old children should be evaluated immediately. The earlier a child receives treatment, the better their outlook.

While signs of autism can sometimes be seen as early as 12 months, most children with autism receive a diagnosis after age 3.

Signs of autism become more apparent as children age.

Your child may exhibit some of the following signs of autism:

Social skills

  • doesn’t respond to their name
  • avoids eye contact
  • prefers playing alone than playing with others
  • doesn’t share well with others or take turns
  • doesn’t participate in pretend play
  • doesn’t tell stories
  • isn’t interested in interacting or socializing with others
  • doesn’t like or actively avoids physical contact
  • isn’t interested or doesn’t know how to make friends
  • doesn’t make facial expressions or makes inappropriate expressions
  • cannot be easily soothed or comforted
  • has difficulty expressing or talking about their feelings
  • has difficulty understanding other people’s feelings

Language and communication skills

  • can’t form sentences
  • repeats words or phrases over and over
  • doesn’t answer questions appropriately or follow directions
  • doesn’t understand counting or time
  • reverses pronouns (for example, says “you” instead of “I”)
  • rarely or never uses gestures or body language like waving or pointing
  • talks in a flat or sing-song voice
  • doesn’t understand jokes, sarcasm, or teasing

Irregular behaviors

  • performs repetitive motions (flaps hands, rocks back and forth, spins)
  • lines up toys or other objects in an organized fashion
  • gets upset or frustrated by small changes in daily routine
  • plays with toys the same way every time
  • likes certain parts of objects (often wheels or spinning parts)
  • has obsessive interests
  • has to follow certain routines

Other autism signs in 4-year-olds

These signs are usually accompanied by some of the other signs listed above:

  • hyperactivity or short attention span
  • impulsivity
  • aggression
  • self-injures (punching or scratching self)
  • temper tantrums
  • irregular reaction to sounds, smells, tastes, sights, or textures
  • irregular eating and sleeping habits
  • inappropriate emotional reactions
  • shows lack of fear or more fear than expected

ASD encompass a broad range of signs and symptoms that present with varying degrees of severity.

According to the American Psychiatric Association’s diagnostic criteria, there are three levels of autism. They’re based on how much support is required. The lower the level, the less likely support is needed.

Here’s a breakdown of the levels:

Level 1

  • little interest in social interactions or social activities
  • difficulty initiating social interactions or maintaining conversations
  • trouble with appropriate communication (volume or tone of speech, reading body language, social cues)
  • trouble adapting to changes in routine or behavior
  • difficulty making friends

Level 2

  • difficulty coping with change to routine or surroundings
  • significant lack of verbal and nonverbal communication skills
  • severe and obvious behavior challenges
  • repetitive behaviors that interfere with daily life
  • unusual or reduced ability to communicate or interact with others
  • narrow, specific interests
  • requires daily support

Level 3

  • nonverbal or significant verbal impairment
  • limited ability to communicate, only when requires needs to be met
  • very limited desire to engage socially or participate in social interactions
  • extreme difficulty coping with unexpected change to routine or environment
  • great distress or difficulty changing focus or attention
  • repetitive behaviors, fixed interests, or obsessions that cause significant impairment
  • requires significant daily support

Doctors diagnose autism in children by observing them at play and interacting with others.

There are specific developmental milestones that most children achieve by the time they’re 4 years old, such as having a conversation or telling a story.

If your 4-year-old has signs of autism, your doctor may refer you to a specialist for a more thorough examination.

These specialists will observe your child while they play, learn, and communicate. They’ll also interview you about behaviors you’ve noticed at home.

While the ideal age to diagnose and treat the symptoms of autism is age 3 and younger, the sooner your child receives treatment, the better.

Under the Individuals with Disabilities Education Act (IDEA), all states are required to provide an adequate education to school-age children with developmental issues.

Contact your local school district to find out what resources are available for preschool-age children. You can also take a look at this resource guide from Autism Speaks to see what services are available in your state.

Autism questionnaire

The Modified Checklist for Autism in Toddlers (M-CHAT) is a screening tool that parents and caregivers can use to identify children who may have autism.

This questionnaire is usually used in toddlers up to 2 1/2 years old, but may still be valid in children up to 4 years old. It doesn’t offer a diagnosis, but it may give you an idea of where your child stands.

If your child’s score on this checklist suggests they may have autism, visit your child’s doctor or an autism specialist. They can confirm a diagnosis.

Keep in mind this questionnaire is often used for younger children. Your 4-year-old could fall into the normal range with this questionnaire and still have autism or another developmental disorder. It’s best to take them to their doctor.

Organizations like Autism Speaks offer this questionnaire online.

Signs of autism are usually evident by 4 years old. If you’ve noticed signs of autism in your child, it’s important to get them screened by a doctor as soon as possible.

You can start by going to your child’s pediatrician to explain your concerns. They can give you a referral to a specialist in your area.

Specialists that can diagnose children with autism include:

  • developmental pediatricians
  • child neurologists
  • child psychologists
  • child psychiatrists

If your child receives an autism diagnosis, treatment will begin immediately. You’ll work with your child’s doctors and school district to map out a treatment plan so your child’s outlook is a success.