Autism touches many lives across the world. In the U.S. about 1 in 36 children has autism, according to the Centers for Disease Control and Prevention (CDC). It is thought to be about three times more common in boys than girls, but experts are getting better at recognizing autism in girls. Autism is identified in all racial and ethnic groups.

There are roadblocks to identifying autism and finding the right supports because it can show up differently in each person. For example, some people have significant intellectual disability while others do not. Some people may have seizures or digestive problems, while others have none.

As a parent, this can leave you unsure about what traits to be aware of in your child. Maybe you've noticed some differences in how your child is learning or interacting but are wondering if you should have your child evaluated for autism. Our experts at the UC Davis MIND Institute help answer these questions in this blog.

What is autism?

Autism is a developmental condition caused by differences in the brain. This can lead to challenges communicating, interacting and learning without support.

Autistic people may behave, communicate and learn in ways that are different than other people. They do not look different than anyone else. Some people with autism have good conversation skills, while others may be unable to speak.

Autism begins before a child is 3 years old and lasts their entire life. Some characteristics of autism can show up in the child's first 12 months while some don't show traits until later.

Some autistic children meet developmental milestones until about 18 to 24 months of age. Then they sometimes stop learning new skills or lose skills they once had.

Learn more about autism from the American Psychiatric Association

Get autism resources from the UC Davis MIND Institute

What causes autism?

For some people, autism is caused by a genetic condition. For others, the cause is not yet known. Scientists believe there are multiple causes of autism that act together to change the ways people develop, according to the CDC.

What are some signs of autism?

Some children show traits of autism within the first year. Others may show signs as late as 2 or 3 years of age or older. Not all autistic children show all the signs. Many children who don't have autism show a few of these traits, as well. That's why it's important to have your child evaluated by a health care provider.

Here are some characteristics that may indicate your child has autism, according to the CDC:

By 9 months

  • Does not respond to name
  • Does not show facial expressions like happy, sad, angry and surprised

By 12 months

  • Does not play simple games like pat-a-cake
  • Uses few or no gestures (such as waving goodbye)

By 15 months, does not share interests with others (such as showing you an object they like).

By 18 months, does not point to show you something interesting.

By 24 months, does not notice when others are hurt or upset.

By 36 months, does not notice other children and join them in play.

By 48 months, does not pretend to be something else, like a teacher or superhero.

By 60 months, does not sing, dance or act for you.

At any age:

  • Avoids or does not keep eye contact
  • Lines up toys or other objects and gets upset when order is changed
  • Repeats words or phrases over and over (known as echolalia)
  • Plays with toys the same way every time
  • Is focused on parts of objects (like wheels)
  • Gets upset by minor changes
  • Has obsessive interests
  • Must follow certain routines
  • Flaps hands, rocks body or spins self in circles
  • Has unusual reactions to the way things sound, smell, taste, look or feel

Learn the three early signs of autism

How do I know if I should get my child an autism evaluation?

If you child shows any of the above characteristics during that age range, talk to your child's pediatrician. You can ask them for an autism evaluation. Help Me Grow Sacramento also has information about general developmental screenings.  

As always, if you have any concerns about your child's development, you should talk to their health care provider.

Learn about the Autism Phenome Project, one of the largest long-term studies of its kind in the world

Learn about the MIND Institute's Center for Excellence in Developmental Disabilities

Check out the MIND Institute's Resource Center

Learn more about autism in these UC Davis Health news stories