Signs and Symptoms of Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a developmental disability caused by differences in the brain. People with ASD often have problems with social communication and interaction, and restricted or repetitive behaviors or interests. People with ASD may also have different ways of learning, moving, or paying attention. It is important to note that some people without ASD might also have some of these symptoms. But for people with ASD, these characteristics can make life very challenging.
Social Communication and Interaction Skills
Social communication and interaction skills can be challenging for people with ASD.
Examples of social communication and social interaction characteristics related to ASD can include
- Avoids or does not keep eye contact
- Does not respond to name by 9 months of age
- Does not show facial expressions like happy, sad, angry, and surprised by 9 months of age
- Does not play simple interactive games like pat-a-cake by 12 months of age
- Uses few or no gestures by 12 months of age (for example, does not wave goodbye)
- Does not share interests with others by 15 months of age (for example, shows you an object that they like)
- Does not point to show you something interesting by 18 months of age
- Does not notice when others are hurt or upset by 24 months of age
- Does not notice other children and join them in play by 36 months of age
- Does not pretend to be something else, like a teacher or superhero, during play by 48 months of age
- Does not sing, dance, or act for you by 60 months of age
Restricted or Repetitive Behaviors or Interests
People with ASD have behaviors or interests that can seem unusual. These behaviors or interests set ASD apart from conditions defined by problems with social communication and interaction only.
Examples of restricted or repetitive behaviors and interests related to ASD can include
- Lines up toys or other objects and gets upset when order is changed
- Repeats words or phrases over and over (called echolalia)
- Plays with toys the same way every time
- Is focused on parts of objects (for example, 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
Most people with ASD have other related characteristics. These might include
- Delayed language skills
- Delayed movement skills
- Delayed cognitive or learning skills
- Hyperactive, impulsive, and/or inattentive behavior
- Epilepsy or seizure disorder
- Unusual eating and sleeping habits
- Gastrointestinal issues (for example, constipation)
- Unusual mood or emotional reactions
- Anxiety, stress, or excessive worry
- Lack of fear or more fear than expected
What Is Autism?
There is no one type of autism, but many.
Autism, or autism spectrum disorder (ASD), refers to a broad range of conditions characterized by challenges with social skills, repetitive behaviors, speech and nonverbal communication. According to the Centers for Disease Control, autism affects an estimated 1 in 44 children in the United States today.
We know that there is not one autism but many subtypes, most influenced by a combination of genetic and environmental factors. Because autism is a spectrum disorder, each person with autism has a distinct set of strengths and challenges. The ways in which people with autism learn, think and problem-solve can range from highly skilled to severely challenged. Some people with ASD may require significant support in their daily lives, while others may need less support and, in some cases, live entirely independently.
Several factors may influence the development of autism, and it is often accompanied by sensory sensitivities and medical issues such as gastrointestinal (GI) disorders, seizures or sleep disorders, as well as mental health challenges such as anxiety, depression and attention issues.
Signs of autism usually appear by age 2 or 3. Some associated development delays can appear even earlier, and often, it can be diagnosed as early as 18 months. Research shows that early intervention leads to positive outcomes later in life for people with autism.
What is Autism Spectrum Disorder?
Autism spectrum disorder (ASD) is a developmental disability caused by differences in the brain. Some people with ASD have a known difference, such as a genetic condition. Other causes are not yet known. Scientists believe there are multiple causes of ASD that act together to change the most common ways people develop. We still have much to learn about these causes and how they impact people with ASD.
People with ASD may behave, communicate, interact, and learn in ways that are different from most other people. There is often nothing about how they look that sets them apart from other people. The abilities of people with ASD can vary significantly. For example, some people with ASD may have advanced conversation skills whereas others may be nonverbal. Some people with ASD need a lot of help in their daily lives; others can work and live with little to no support.
ASD begins before the age of 3 years and can last throughout a person’s life, although symptoms may improve over time. Some children show ASD symptoms within the first 12 months of life. In others, symptoms may not show up until 24 months of age or later. Some children with ASD gain new skills and meet developmental milestones until around 18 to 24 months of age, and then they stop gaining new skills or lose the skills they once had.
As children with ASD become adolescents and young adults, they may have difficulties developing and maintaining friendships, communicating with peers and adults, or understanding what behaviors are expected in school or on the job. They may come to the attention of healthcare providers because they also have conditions such as anxiety, depression, or attention-deficit/hyperactivity disorder, which occur more often in people with ASD than in people without ASD.
Signs and Symptoms
People with ASD often have problems with social communication and interaction, and restricted or repetitive behaviors or interests. People with ASD may also have different ways of learning, moving, or paying attention. It is important to note that some people without ASD might also have some of these symptoms. For people with ASD, these characteristics can make life very challenging.
Diagnosing ASD can be difficult since there is no medical test, like a blood test, to diagnose the disorder. Doctors look at the child’s behavior and development to make a diagnosis. ASD can sometimes be detected at 18 months of age or younger. By age 2, a diagnosis by an experienced professional can be considered reliable.1 However, many children do not receive a final diagnosis until they are much older. Some people are not diagnosed until they are adolescents or adults. This delay means that people with ASD might not get the early help they need.
Current treatments for ASD seek to reduce symptoms that interfere with daily functioning and quality of life. ASD affects each person differently, meaning that people with ASD have unique strengths and challenges and different treatment needs.2 Treatment plans usually involve multiple professionals and are catered to the individual.
There is not just one cause of ASD. There are many different factors that have been identified that may make a child more likely to have ASD, including environmental, biologic, and genetic factors.
Although we know little about specific causes, the available evidence suggests that the following may put children at greater risk for developing ASD:
- Having a sibling with ASD
- Having certain genetic or chromosomal conditions, such as fragile X syndrome or tuberous sclerosis
- Experiencing complications at birth
- Being born to older parents
CDC is currently working on one of the largest U.S. studies to date on ASD. This study called the Study to Explore Early Development (SEED), was designed to look at the risk factors and behaviors related with ASD. CDC is now conducting a follow-up study of older children who were enrolled in SEED to determine the health, functioning, and needs of people with ASD and other developmental disabilities as they mature.
How Often ASD Occurs
CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network has been estimating the number of 8-year-old children with ASD in the United States since 2000.
ASD occurs in all racial, ethnic, and socioeconomic groups. It is more than 4 times more common among boys than among girls.
If You’re Concerned
As a parent, you already have what it takes to help your young child learn and grow. CDC has developed materials to help you track your child’s developmental milestones and share that progress, or any concerns, with your child’s doctor at every check-up.
Contact your child’s doctor if you think your child might have ASD or if you have any other concerns about the way your child plays, learns, speaks, or acts.
If you are still concerned, ask the doctor for a referral to a specialist who can do a more in-depth evaluation of your child. Specialists who can do a more in-depth evaluation and make a diagnosis include
- Developmental pediatricians (doctors who have special training in child development and children with special needs)
- Child neurologists (doctors who work on the brain, spine, and nerves)
- Child psychologists or psychiatrists (doctors who know about the human mind)
At the same time, call your state’s public early childhood system to request a free evaluation, sometimes called a Child Find evaluation, to find out if your child qualifies for intervention services. You do not need to wait for a doctor’s referral or a medical diagnosis to make this call.
Where to call for a free evaluation from the state depends on your child’s age:
- If your child is not yet 3 years old, contact your local early intervention system.
- You can find the right contact information for your state by calling the Early Childhood Technical Assistance Center (ECTA) at 919-962-2001.
- Or visit the ECTA website. external icon
- If your child is 3 years old or older, contact your local public school system.
- Even if your child is not yet old enough for kindergarten or enrolled in a public school, call your local elementary school or board of education and ask to speak with someone who can help you have your child evaluated.
- If you’re not sure who to contact, call the ECTA at 919-962-2001.
- Or visit the ECTA website. external icon
Research shows that early intervention services can greatly improve a child’s development. In order to make sure your child reaches their full potential, it is very important to receive services as soon as possible.
Autism Spectrum Disorder
Autism spectrum disorder (ASD) is a neurological and developmental disorder that affects how people interact with others, communicate, learn, and behave. Although autism can be diagnosed at any age, it is described as a “developmental disorder” because symptoms generally appear in the first two years of life.
According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), a guide created by the American Psychiatric Association that health care providers use to diagnose mental disorders, people with ASD often have:
- Difficulty with communication and interaction with other people
- Restricted interests and repetitive behaviors
- Symptoms that affect their ability to function in school, work, and other areas of life
Autism is known as a “spectrum” disorder because there is wide variation in the type and severity of symptoms people experience.
People of all genders, races, ethnicities, and economic backgrounds can be diagnosed with ASD. Although ASD can be a lifelong disorder, treatments and services can improve a person’s symptoms and daily functioning. The American Academy of Pediatrics recommends that all children receive screening for autism. Caregivers should talk to their child’s health care provider about ASD screening or evaluation.
Signs and Symptoms of ASD
People with ASD have difficulty with social communication and interaction, restricted interests, and repetitive behaviors. The list below gives some examples of common types of behaviors in people diagnosed with ASD. Not all people with ASD will have all behaviors, but most will have several of the behaviors listed below.
Social communication / interaction behaviors may include:
- Making little or inconsistent eye contact
- Appearing not to look at or listen to people who are talking
- Infrequently sharing interest, emotion, or enjoyment of objects or activities (including by infrequently pointing at or showing things to others)
- Not responding or being slow to respond to one’s name or to other verbal bids for attention
- Having difficulties with the back and forth of conversation
- Often talking at length about a favorite subject without noticing that others are not interested or without giving others a chance to respond
- Displaying facial expressions, movements, and gestures that do not match what is being said
- Having an unusual tone of voice that may sound sing-song or flat and robot-like
- Having trouble understanding another person’s point of view or being unable to predict or understand other people’s actions
- Difficulties adjusting behaviors to social situations
- Difficulties sharing in imaginative play or in making friends
Restrictive / repetitive behaviors may include:
- Repeating certain behaviors or having unusual behaviors, such as repeating words or phrases (a behavior called echolalia)
- Having a lasting intense interest in specific topics, such as numbers, details, or facts
- Showing overly focused interests, such as with moving objects or parts of objects
- Becoming upset by slight changes in a routine and having difficulty with transitions
- Being more sensitive or less sensitive than other people to sensory input, such as light, sound, clothing, or temperature
People with ASD may also experience sleep problems and irritability.
People on the autism spectrum also may have many strengths, including:
- Being able to learn things in detail and remember information for long periods of time
- Being strong visual and auditory learners
- Excelling in math, science, music, or art
Causes and Risk Factors
Researchers don’t know the primary causes of ASD, but studies suggest that a person’s genes can act together with aspects of their environment to affect development in ways that lead to ASD. Some factors that are associated with an increased likelihood of developing ASD include:
- Having a sibling with ASD
- Having older parents
- Having certain genetic conditions (such as Down syndrome or Fragile X syndrome)
- Having a very low birth weight
Health care providers diagnose ASD by evaluating a person’s behavior and development. ASD can usually be reliably diagnosed by the age of two. It is important to seek an evaluation as soon as possible. The earlier ASD is diagnosed, the sooner treatments and services can begin.
Diagnosis in Young Children
Diagnosis in young children is often a two-stage process.
Stage 1: General Developmental Screening During Well-Child Checkups
Every child should receive well-child check-ups with a pediatrician or an early childhood health care provider. The American Academy of Pediatrics recommends that all children receive screening for developmental delays at their 9-, 18-, and 24- or 30-month well-child visits, with specific autism screenings at their 18- and 24-month well-child visits. A child may receive additional screening if they are at high risk for ASD or developmental problems. Children at high risk include those who have a family member with ASD, show some behaviors that are typical of ASD, have older parents, have certain genetic conditions, or who had a very low birth weight.
Considering caregivers’ experiences and concerns is an important part of the screening process for young children. The health care provider may ask questions about the child’s behaviors and evaluate those answers in combination with information from ASD screening tools and clinical observations of the child. Read more about screening instruments on the Centers for Disease Control and Prevention (CDC) website.
If a child shows developmental differences in behavior or functioning during this screening process, the health care provider may refer the child for additional evaluation.
Stage 2: Additional Diagnostic Evaluation
It is important to accurately detect and diagnose children with ASD as early as possible, as this will shed light on their unique strengths and challenges. Early detection also can help caregivers determine which services, educational programs, and behavioral therapies are most likely to be helpful for their child.
A team of health care providers who have experience diagnosing ASD will conduct the diagnostic evaluation. This team may include child neurologists, developmental pediatricians, speech-language pathologists, child psychologists and psychiatrists, educational specialists, and occupational therapists.
The diagnostic evaluation is likely to include:
- Medical and neurological examinations
- Assessment of the child’s cognitive abilities
- Assessment of the child’s language abilities
- Observation of the child’s behavior
- An in-depth conversation with the child’s caregivers about the child’s behavior and development
- Assessment of age-appropriate skills needed to complete daily activities independently, such as eating, dressing, and toileting
Because ASD is a complex disorder that sometimes occurs with other illnesses or learning disorders, the comprehensive evaluation may include:
- Blood tests
- Hearing test
The outcome of the evaluation may result in a formal diagnosis and recommendations for treatment.
Diagnosis in older children and adolescents
Caregivers and teachers are often the first to recognize ASD symptoms in older children and adolescents who attend school. The school’s special education team may perform an initial evaluation and then recommend that a child undergo additional evaluation with their primary health care provider or a health care provider who specialize in ASD.
A child’s caregivers may talk with these health care providers about their child’s social difficulties, including problems with subtle communication. These subtle communication differences may include problems understanding tone of voice, facial expressions, or body language. Older children and adolescents may have trouble understanding figures of speech, humor, or sarcasm. They also may have trouble forming friendships with peers.
Diagnosis in adults
Diagnosing ASD in adults is often more difficult than diagnosing ASD in children. In adults, some ASD symptoms can overlap with symptoms of other mental health disorders, such as anxiety disorder or attention-deficit/hyperactivity disorder (ADHD).
Adults who notice the signs and symptoms of ASD should talk with a health care provider and ask for a referral for an ASD evaluation. Although evaluation for ASD in adults is still being refined, adults can be referred to a neuropsychologist, psychologist, or psychiatrist who has experience with ASD. The expert will ask about:
- Social interaction and communication challenges
- Sensory issues
- Repetitive behaviors
- Restricted interests
The evaluation also may include a conversation with caregivers or other family members to learn about the person’s early developmental history, which can help ensure an accurate diagnosis.
Obtaining a correct diagnosis of ASD as an adult can help a person understand past challenges, identify personal strengths, and find the right kind of help. Studies are underway to determine the types of services and supports that are most helpful for improving the functioning and community integration of autistic transition-age youth and adults.
Treatments and Therapies
Treatment for ASD should begin as soon as possible after diagnosis. Early treatment for ASD is important as proper care and services can reduce individuals’ difficulties while helping them learn new skills and build on their strengths.
People with ASD may face a wide range of issues, which means that there is no single best treatment for ASD. Working closely with a health care provider is an important part of finding the right combination of treatment and services.
A health care provider may prescribe medication to treat specific symptoms. With medication, a person with ASD may have fewer problems with:
- Repetitive behavior
- Attention problems
- Anxiety and depression
Read more about the latest medication warnings, patient medication guides, and information on newly approved medications at the Food and Drug Administration (FDA) website.
Behavioral, psychological, and educational interventions
People with ASD may be referred to a health care provider who specializes in providing behavioral, psychological, educational, or skill-building interventions. These programs are typically highly structured and intensive, and they may involve caregivers, siblings, and other family members. These programs may help people with ASD:
- Learn social, communication, and language skills
- Reduce behaviors that interfere with daily functioning
- Increase or build upon strengths
- Learn life skills necessary for living independently