Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition typically diagnosed during childhood. The former name of ASD is autism, and many people still use the term. But ASD includes several conditions within the spectrum. ASD changes the way your child interacts and communicates. There’s no cure for autism, but the symptoms may lessen over time.


What is autism?

Autism, now called autism spectrum disorder (ASD), is a neurodevelopmental disorder. ASD is a developmental disability caused by differences in your child’s brain. People with ASD may behave, interact and learn in ways that are different from other people. They may have trouble with social interactions and with interpreting and using nonverbal and verbal communication.

Autism definition

Autism means your child may have:

  • Difficulties interacting with other people or differences in how they interact with others.
  • Trouble using and understanding nonverbal communication, like eye contact, gestures and facial expressions.
  • Delayed or absent language development.
  • Trouble forming and understanding relationships.
  • Repetitive motor behaviors, like flapping arms, body rocking or repetitive speech or play.
  • Insistence on sameness in environment or routine.
  • Intense or unusual interests.
  • Sensory aversions, like dislike of loud noises, or sensory-seeking behaviors.

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

Autism vs. autism spectrum disorder (ASD) — what’s the difference?

The American Psychiatric Association changed the term autism to autism spectrum disorder in 2013. ASD is now an umbrella term that covers the different levels of autism. The autism spectrum includes conditions that providers used to consider separate, including:

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

Asperger vs. autism — what’s the difference?

Healthcare providers don’t officially recognize Asperger syndrome as its own condition anymore. They used to consider Asperger and autism as different conditions. The symptoms that were once part of an Asperger’s diagnosis now fall under the autism spectrum. Providers consider Asperger’s a mild form of autism. Some people still use the term Asperger’s syndrome to describe their condition.

What is high-functioning autism?

High-functioning autism isn’t an official medical diagnosis. However, some people use the term to describe a mild form of autism that requires lower levels of support. People on the mild end of the autism spectrum can speak, read, write and handle basic life skills. Providers used to call this Asperger syndrome.

Autism vs. ADHD — is ADHD on the autism spectrum?

Autism spectrum disorder and attention-deficit/hyperactivity disorder (ADHD) have many similarities, but ADHD isn’t on the autism spectrum. The symptoms of ADHD and autism can overlap. Both conditions cause children to have trouble paying attention, and both can affect their social skills. These overlapping symptoms can sometimes lead to incorrect diagnoses.

ADHD and autism are related genetically, as well. Having one of these conditions increases your child’s risk of having the other. And a child with autism has a higher chance of having a close relative with ADHD.

How common is autism?

According to the Centers for Disease Control and Prevention, ASD affects about 1 in every 44 8-year-old children.

Autism in boys and children assigned male at birth (AMAB) is much more likely than autism in girls and children assigned female at birth (AFAB). It’s more than four times more common in boys and children AMAB than in girls and children AFAB.

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

Researchers believe ASD is a disorder of very early brain development. The behavioral signs of autism characteristics typically surface between the ages of 1.5 and 3 years old.


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Symptoms and Causes

How to recognize signs of autism.

What are the symptoms of autism?

Autism symptoms range from mild to severely disabling, and every person is different. You should consider the following signs of autism as possible indicators that your child may be at risk for the condition. If your child shows any of the following early signs of autism, get in touch with their healthcare provider. They may recommend a referral for an autism evaluation.

Signs of autism include difficulties with social interactions, such as:

  • Your child doesn’t look at you when you call their name or responds inconsistently.
  • Your baby doesn’t smile widely or make warm, joyful expressions by the age of 6 months.
  • Your baby doesn’t engage in smiling, making sounds and making faces with you or other people by the age of 9 months.
  • Your baby doesn’t babble by the age of 12 months.
  • Your baby doesn’t use gestures such as reaching or waving by the age of 12 months.
  • Your baby doesn’t play any back-and-forth games, like “peek-a-boo,” by the age of 12 months.
  • Your toddler doesn’t say any words by the age of 16 months.
  • Your toddler doesn’t speak any meaningful, two-word phrases (not including imitating or repeating) by the age of 24 months.
  • Any loss of speech, babbling or social skills.

Signs of autism also include specific behaviors, called restricted or repetitive behaviors or interests:

  • Your child often lines up toys or plays with toys the same way every time.
  • Your child must follow certain routines or has extreme reactions to small changes in routine.
  • Your child has obsessive or very unusual interests.
  • Your child has significant sensory aversions, like dislike of loud noises, dislike of how certain clothes fit or feel or very picky eating.
  • Your child has sensory-seeking behaviors, like looking out of the corner of their eye at objects (peering), sniffing or licking objects.

What causes autism?

There’s no clear-cut cause of ASD. Research supports genetic and environmental factors as some causes of autism. Scientists believe there could be many different causes of ASD that act together to change the ways people develop. They still have a lot to learn about the causes and how they impact people with ASD.

Is autism genetic?

Genetics do play a role in autism. But healthcare providers have only identified specific genetic causes in 10% to 20% of cases. These cases include specific genetic syndromes associated with ASD, such as fragile X syndrome, and rare changes in genetic code.

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

Autism is hereditary. When one child receives an ASD diagnosis, the next child has about a 20% greater risk of developing autism than normal. When the first two children in a family have 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 don’t 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 risk factors for autism?

This field of study is an active one for research. Current known risk factors for autism include:


What are the complications of autism?

A wide range of physical and mental conditions often come along with autism. These conditions may include:

Diagnosis and Tests

How is autism diagnosed?

Getting an autism diagnosis can be difficult. There’s no autism test, such as a laboratory test, to diagnose the condition. However, healthcare providers can perform specialized screenings and evaluations. The steps in the process of getting an autism diagnosis include the following.

Developmental surveillance

Your child’s healthcare provider will look at your child’s developmental history and behavior. They’ll likely ask you to record your own observations to share with them at your child’s appointments. This is an active, ongoing process where you watch your child grow and discuss your child’s skills and abilities with their provider.

Developmental screening

Screening is a more formal step and takes a closer look at your child’s development. Your child’s provider may utilize a questionnaire to screen for autism. This includes questions and checklists to compare your child to other children of the same age. This test doesn’t provide a diagnosis, but it can indicate if your child is on the typical developmental track or needs a more formal evaluation.

Formal evaluation

Formal evaluation takes a more in-depth look at your child’s development. A trained specialist, such as a child psychologist or a developmental-behavioral pediatrician, will observe your child and give them a structured autism spectrum test. They’ll also ask you questions and have you fill out questionnaires. The results of a formal evaluation will show your child’s strengths and challenges and can help determine a formal diagnosis.


Management and Treatment

Can autism be cured?

ASD is most often a lifelong condition that has no cure. However, your child’s symptoms may get milder as they get older.

How is autism treated?

Autism treatment includes behavioral interventions or therapies. These teach new skills to address the core deficits of autism and reduce the core symptoms. Every child with autism is unique. For this reason, your child will receive an individualized treatment plan to meet their specific needs. It’s best to begin interventions as soon as possible so the benefits of therapy can continue throughout your child’s life.

Many people with ASD have additional medical conditions. These include gastrointestinal and feeding issues, seizures and sleep disturbances. Treatment can involve behavioral therapy, medications or both.

Early intensive behavioral treatments involve your entire family and possibly a team of professionals. As your child ages and develops, they may receive a modified treatment plan to cater to their specific needs.

During adolescence, children may benefit from transition services. These can promote skills of independence essential in adulthood. The focus at that point is on employment opportunities and job skill training.


Can autism be prevented?

You can’t prevent autism, but you can lower your risk of having a baby with the condition by taking certain steps, including:

  • Live a healthy lifestyle: Make sure you see your healthcare provider regularly, eat a nutritious diet and exercise. Get prenatal care, and take your provider’s recommended vitamins and supplements.
  • Take care with medications: Ask your healthcare provider which medications are safe and which you should stop taking during your pregnancy.
  • Don’t drink: No kind and no amount of alcohol is safe during pregnancy.
  • Keep up with your vaccinations: Get all of your provider’s recommended vaccines, including the German measles (rubella) vaccine, before you get pregnant. This vaccine can prevent rubella-associated autism.

Outlook / Prognosis

What is the outlook for people with autism spectrum disorder (ASD)?

In many cases, the symptoms of ASD become milder as children get older. You may need to be flexible and ready to adjust treatment as needed for your child.

People with ASD may go on to live typical lives, but there’s often a need for continued services and support as they age. Their needs depend on the severity of their symptoms. For most, it’s a lifelong condition that may require ongoing support.

Additional Common Questions

Do I have autism?

Though most people with autism receive their diagnosis during childhood, many don’t until adulthood. The most recent data suggests autism in adults affects more than 5 million people in the U.S., or 2.21% of the population. Signs of autism in adults may include:

  • Having difficulty understanding what others are feeling or thinking.
  • Extreme anxiety in social situations.
  • Trouble making friends or preferring to be on your own.
  • Coming off as rude, blunt or not interested in others but not meaning to.
  • Difficulty expressing your feelings.
  • Need for a consistent routine and getting anxious if it changes.
  • Avoiding eye contact.
  • Problems with appropriate space, such as getting too close to other people.

Autism in women and people AFAB can sometimes be different than autism in men and people AMAB.

Many women and people AFAB learn to hide the signs of autism to “fit into” society by copying people who don’t have autism. In addition, they’re quieter and tend to hide their feelings. Women and people AFAB appear to cope better in social situations than men and people AMAB. They also show fewer signs of repetitive behaviors.

If you think you may have autism, speak with a healthcare provider. Although there are adult autism tests online, only a trained specialist can diagnose the condition.

Is autism a disability?

Yes, healthcare providers classify autism as a disability. The Americans with Disabilities Act (ADA) protects people with autism spectrum disorder. This means they may receive certain benefits. Employers must provide reasonable accommodations in the workplace. Schools must provide accommodations to students. Depending on the level of support you need, you may also be eligible for disability benefits, including Social Security and Medicaid.

A note from Cleveland Clinic

Over the past 20 years, researchers have learned a lot about autism spectrum disorder. There’s ongoing, active research on the causes of ASD, early diagnosis, prevention and treatments. If you suspect your child may have autism, reach out to their healthcare provider. They’ll be able to walk you through the steps of getting a diagnosis and starting treatment.

Medically Reviewed

Last reviewed on 02/26/2023.

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