Autism is a difference in how your child’s brain works that causes them to socialize and behave in unique ways. Early signs of autism include limited eye contact and body language and repetitive motions or speech. Behavioral therapies and other support can help autistic kids (and adults) make the most of their strengths and manage any challenges.
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Autism is a difference in how your child’s brain works that shapes how they interact with the world around them. We don’t know exactly why some people are autistic and others aren’t. But we do know:
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
When discussing autism, it’s important to acknowledge that words aren’t perfect. And sometimes, “medspeak” that healthcare providers use — like “disorder,” “symptoms” or “diagnosis” — doesn’t quite match the lived experience of autistic people or their families.
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Throughout this article, we’ll use such medical terms as needed to describe how healthcare providers can support your family. But we recognize that autism is an identity, not just a diagnosis.
We use the term “autistic” to reflect the preferences of the autistic community, which largely prefers identity-first language.
Autism spectrum disorder (ASD) is the full medical name for autism. The DSM-5-TR defines ASD as a difference in brain functioning that affects how you communicate and interact with others. For example, you may use eye contact or body language differently than someone who’s neurotypical.
This brain difference also affects various aspects of your behavior, interests or activities. For example, you may repeat movements or sounds (a behavior known as “stimming”) to regulate your emotions. You may prefer a fixed routine over change.
About 1 in every 31 kids in the U.S. has ASD.
Autism characteristics fall into two main groups:
Below are some examples of autism characteristics you might recognize in your child at different ages.
You may notice your toddler:
You may notice your older child:
You may notice your adolescent:
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You may notice your toddler:
You may notice your older child or adolescent:
There’s not always a clear line between what’s a feature of autism and what’s a kid simply being a kid. Lots of the things above are true for all children at one point or another. But with autism, these behaviors are more than a phase. And they may pose challenges for your child in certain settings, like school or socializing with peers.
Researchers have found a wide range of strengths among autistic people. Your child may have:
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Experts haven’t found a single cause of autism. It’s likely a combination of genetics and certain things related to pregnancy, labor and delivery. You might see these things described as “environmental factors” or “prenatal events.” These factors all interact to lead to the brain differences we see in autism.
Specific things that may make autism more likely in your child include:
These factors may directly change how your baby’s brain develops. Or they may affect how certain genes work, leading to brain differences, in turn.
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Yes — but the genetic causes of autism are complicated. There’s not a single, specific gene variation that’s unique to autism. This makes autism different from some other genetic conditions, like cystic fibrosis, where providers can pinpoint a specific gene variation and say, “Ah! There it is.”
Instead, many gene variations are linked to autism. This means autistic people might have one or more gene variations that play a role in their brain differences.
But there’s not always a clear genetic cause. For example, genetic testing for your child may reveal no gene variations associated with autism. This finding doesn’t change their diagnosis. And it doesn’t rule out a genetic cause. It’s possible that other gene variations contribute to autism, and researchers simply haven’t identified them yet.
It can be. It’s easy to confuse genetics with inheritance. When we say autism is genetic, we mean variations in certain genes affect how your baby’s brain works. Those gene variations might pop up for the first time in your baby — in this case, they’re not inherited.
But it’s also possible for biological parents to pass down gene variations to their children. Experts think autism can be inherited because they see patterns among siblings.
Diagnosing autism involves several steps. Often, the process begins at a routine well-check (annual physical). The American Academy of Pediatrics recommends autism screenings at the 18-month and 24-month visits. A screening means your pediatrician will ask some questions about your child, including how they act, communicate and express emotions.
If your pediatrician notices possible signs of autism, they’ll refer you to a provider who specializes in diagnosing autism. This specialist will talk with you and spend some time observing and interacting with your child. They’ll look for specific symptoms (characteristics) typical of autism.
Providers use the criteria listed in the DSM-5-TR. This diagnostic manual breaks down symptoms into the two main groups discussed earlier: how your child socializes and how they act.
Your child must have difficulties in all three of the following social areas:
AND your child must do at least two of the following:
No, not in the way you might think of a medical test. There aren’t any lab tests or specific markers in blood or pee for autism. Providers may do genetic testing to check for gene variations associated with autism. But genetic testing doesn’t diagnose autism. Instead, it may help narrow down the cause of your child’s brain differences.
When seeking a diagnosis, it helps to see a developmental pediatrician, who’s trained to recognize autism. They can administer a standardized assessment, like the Autism Diagnostic Observation Schedule (ADOS). The ADOS is a set of questions that help providers identify autism characteristics when observing or interacting with your child. The ADOS and similar tools are designed for providers to use in a clinical setting.
There are many different therapies available to support children with autism. These therapies help your child manage any challenges they face and build on their strengths. Some therapies teach you and other family members ways to support your child.
The earlier such support begins — ideally, before age 3 — the more it can benefit your child in the long run.
Some autistic kids have other conditions that need support or treatment. Conditions that may co-occur with autism include:
Providers manage or treat these conditions with things like:
Yes. ASD falls within the umbrella category of neurodevelopmental disorders. These are conditions affecting a child’s brain function that become noticeable early in life — often before or soon after starting school.
In the past, providers used several different names to describe neurodevelopmental disorders with features of autism:
Providers now recognize that autism is a spectrum with a wide range of features, and autistic kids need varying levels of support. So, instead of using these other names, providers use ASD as the official diagnosis. They also describe specific features and needs unique to each child.
Being a parent is a lot like being a student — you’re constantly learning, growing and changing. And so is your child. But there’s no textbook. You learn from your child and all their various needs, interests, behaviors and how they respond to you.
If your child is autistic, your learning might look a little different from what you’d expected. But it’s still the same, basic idea — your child is taking the lead and you’re following their cues. It may help to remember this isn’t an “independent study.” Your child’s healthcare providers are right there with your family for each new challenge or discovery.
There’s hope and caring for kids with autism spectrum disorder. At Cleveland Clinic, we design compassionate, personalized treatments for them.
Last reviewed on 07/15/2025.
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