Autism Spectrum Disorder
What Is Autism Spectrum Disorder?

Autism is more properly called autism spectrum disorder (ASD) because children with ASD can have a broad range of symptoms, skills, and levels of impairment or disability.  

According to the National Institute of Mental Health (http://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-asd/index.shtml) ASD is characterized by:

  • Persistent deficits in social communication and social interaction across multiple contexts;
  • Restricted, repetitive patterns of behavior, interests, or activities;
  • Symptoms must be present in the early developmental period (typically recognized in the first two years of life); and,
  • Symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning.

The Centers for Disease Control and Prevention (CDC) estimates that about 1 in 6 children in the United States had a developmental disability in 2006-2008, ranging from mild disabilities such as speech and language impairments to serious developmental disabilities, such as intellectual disabilities, cerebral palsy, and autism. The CDC estimates that about 1 in 68 children have been identified with ASD. (http://www.cdc.gov/ncbddd/autism/index.html)

ASD is almost 5 times more common among boys (1 in 42) than among girls (1 in 189). Experts disagree about whether there has been a true increase in ASD prevalence because people are now more aware of ASD and the guidelines for diagnosis have changed.  

The exact cause of ASD has not been determined but research suggests that both genes and environment play important roles.

Genetic factors
Most people who develop ASD have no reported family history of autism, but genetic involvement is shown by the fact that if one identical twin has ASD, 9 out of 10 times an identical twin with the exact same genetic code will also have ASD. If one sibling has ASD, the other siblings will have 35 times the normal risk of ASD.
Researchers have had only limited success in identifying specific genes that may increase the risk for ASD.  One genetic disorder that is the most common form of inherited intellectual disability, the Fragile X syndrome, causes symptoms similar to ASD among 1 in 3 children with the condition.  About 1 in 25 children diagnosed with ASD have the mutation that causes Fragile X syndrome.
Because this disorder is inherited, children with ASD should be checked for Fragile X, especially if the parents want to have more children. Other family members who are planning to have children may also want to be checked for Fragile X syndrome. (For more information on Fragile X, see the Eunice Kennedy Shriver National Institute of Child Health and Human Development website .)
Tuberous sclerosis is a rare genetic disorder that causes noncancerous tumors to grow in the brain and other vital organs. Tuberous sclerosis occurs in 1 to 4 percent of people with ASD. A genetic mutation causes the disorder, which has also been linked to intellectual disability, epilepsy, and many other physical and mental health problems. There is no cure for tuberous sclerosis, but many symptoms can be treated.
Having increased genetic risk does not mean a child will definitely develop ASD. Many researchers are focusing on how various genes interact with each other and environmental factors to better understand how they increase the risk of this disorder.

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Environmental Factors
Researchers are studying many environmental factors that may affect risk of ADS, such as family medical conditions, parental age, exposure to toxins in our food, water and environment, maternal health and environmental exposures during pregnancy and complications during pregnancy or birth.  It is not likely that any single environmental risk factor raises the likelihood of ASD.  One possible environmental cause of ADS that has been ruled out is vaccination.  As of 2010, none of the many studies to determine if vaccines are a possible cause of autism has linked autism and vaccines. (See the Timely Topic: Vaccination, for more information on vaccinations.)

Early Signs & Symptoms
Symptoms of autism spectrum disorder (ASD) vary from one child to the next, but in general, according to the NIMH, they fall into two areas:

  • Social impairment, including difficulties with social communication
  • Repetitive and stereotyped behaviors.

Children with ASD do not follow typical patterns when developing social and communication skills.  Even before their first birthday, some babies become overly focused on certain objects, rarely make eye contact, and fail to engage in typical back-and-forth play and babbling with their parents. Other children may develop normally until the second or even third year of life, but then regress, start to lose interest in others and become silent, withdrawn, or indifferent to social signals.

Social Impairment
Most children with ASD have trouble engaging in everyday social interactions. For example, some children with ASD may:

  • Make little eye contact
  • Tend to look and listen less to people in their environment or fail to respond to other people
  • Rarely seek to share their enjoyment of toys or activities by pointing or showing things to others
  • Respond unusually when others show anger, distress, or affection.

Recent research suggests that children with ASD do not respond to emotional cues in human social interactions because they may not pay attention, misread or not notice the subtle social cues that others typically notice. Without the ability to interpret another person's tone of voice as well as gestures, facial expressions, and other nonverbal communications, children with ASD may not properly respond.

Likewise, it can be hard for others to understand the body language of children with ASD. Their facial expressions, movements, and gestures are often vague or do not match what they are saying. Their tone of voice may not reflect their actual feelings either. Many older children with ASD speak with an unusual tone of voice and may sound sing-song or flat and robotlike.

Children with ASD also may have trouble understanding another person's point of view. For example, by school age, most children understand that other people have different information, feelings, and goals than they have. Children with ASD may lack this understanding, leaving them unable to predict or understand other people's actions.

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Communication Issues
According to the American Academy of Pediatrics' developmental milestones, by the first birthday, typical toddlers can say one or two words, turn when they hear their name, and point when they want a toy. When offered something they do not want, toddlers make it clear with words, gestures, or facial expressions that the answer is "no."
For children with ASD, reaching such milestones may not be so straightforward. For example, some children with autism may:

  • Fail or be slow to respond to their name or other verbal attempts to gain their attention
  • Fail or be slow to develop gestures, such as pointing and showing things to others
  • Coo and babble in the first year of life, but then stop doing so
  • Develop language at a delayed pace
  • Learn to communicate using pictures or their own sign language
  • Speak only in single words or repeat certain phrases over and over, seeming unable to combine words into meaningful sentences
  • Repeat words or phrases that they hear, a condition called echolalia
  • Use words that seem odd, out of place, or have a special meaning known only to those familiar with the child's way of communicating.

Even children with ASD who have relatively good language skills often have difficulties with the back and forth of conversations. For example, because they find it difficult to understand and react to social cues, some highly verbal children with ASD often talk at length about a favorite subject, but they won't allow anyone else a chance to respond or notice when others react indifferently.

Children with ASD who have not yet developed meaningful gestures or language may simply scream or grab or otherwise act out until they are taught better ways to express their needs. As these children grow up, they can become aware of their difficulty in understanding others and in being understood. This awareness may cause them to become anxious or depressed.

Repetitive and Stereotyped Behaviors
Children with ASD often have repetitive motions or unusual behaviors. These behaviors may be extreme and very noticeable, or they can be mild and discreet. For example, some children may repeatedly flap their arms or walk in specific patterns, while others may subtly move their fingers by their eyes in what looks to be a gesture. These repetitive actions are sometimes called "stereotypy" or "stereotyped behaviors."

Children with ASD also tend to have overly focused interests. Children with ASD may become fascinated with moving objects or parts of objects, like the wheels on a moving car. They might spend a long time lining up toys in a certain way, rather than playing with them. They may also become very upset if someone accidentally moves one of the toys. Repetitive behavior can also take the form of a persistent, intense preoccupation. For example, they might be obsessed with learning all about vacuum cleaners, train schedules, or lighthouses. Children with ASD often have great interest in numbers, symbols, or science topics.

While children with ASD often do best with routine in their daily activities and surroundings, inflexibility may often be extreme and cause serious difficulties. They may insist on eating the same exact meals every day or taking the same exact route to school. A slight change in a specific routine can be extremely upsetting. Some children may even have emotional outbursts, especially when feeling angry or frustrated or when placed in a new or stimulating environment.

No two children express exactly the same types and severity of symptoms. In fact, many typically developing children occasionally display some of the behaviors common to children with ASD. However, if a child has several ASD-related symptoms, the child should be child screened and evaluated by a health professional experienced with ASD.

Autism spectrum disorder (ASD) diagnosis is often a two-stage process. The first stage involves general developmental screening during well-child checkups with a pediatrician or an early childhood health care provider. Children who show some developmental problems are referred for additional evaluation.

The second stage involves a thorough evaluation by a team of doctors and other health professionals with a wide range of specialties. At this stage, a child may be diagnosed as having ASD or another developmental disorder.

Children with ASD can usually be reliably diagnosed by age 2, though research suggests that some screening tests can be helpful at 18 months or even younger. Many people—including pediatricians, family doctors, teachers, and parents—may minimize signs of ASD at first, believing that children will "catch up" with their peers but the earlier the disorder is diagnosed, the sooner specific interventions may begin. Early intervention can reduce or prevent the more severe disabilities associated with ASD and may also improve a child's IQ, language, and everyday functional skills, also called adaptive behavior.

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A well-child checkup should include a developmental screening test, with specific ASD screening at 18 and 24 months as recommended by the American Academy of Pediatrics. Screening for ASD is just a first step and not the same as diagnosing ASD.  Because parental concerns about a child's development are very important in the screening process, it is a good idea to keep notes about the child's development and behavior and when the child reached certain developmental milestones.

Types of ASD Screening Instruments
Examples of screening instruments for toddlers and preschoolers include:

  • Checklist of Autism in Toddlers (CHAT)
  • Modified Checklist for Autism in Toddlers (M-CHAT)
  • Screening Tool for Autism in Two-Year-Olds (STAT)
  • Social Communication Questionnaire (SCQ)
  • Communication and Symbolic Behavior Scales (CSBS).

To screen for mild ASD in older children, a doctor may rely on different screening instruments, such as:

  • Autism Spectrum Screening Questionnaire (ASSQ)
  • Australian Scale for Asperger's Syndrome (ASAS)
  • Childhood Asperger Syndrome Test (CAST).

Some helpful resources on ASD screening include the Center for Disease Control and Prevention's General Developmental Screening tools and ASD Specific Screening tools on their website.

Comprehensive Diagnostic Evaluation
The second stage of diagnosis must be thorough in order to find whether other conditions may be causing a child's symptoms.
A team that includes a psychologist, a neurologist, a psychiatrist, a speech therapist, or other professionals experienced in diagnosing ASD may do this evaluation. The evaluation may assess the child's cognitive level (thinking skills), language level, and adaptive behavior (age-appropriate skills needed to complete daily activities independently, for example eating, dressing, and toileting).

Because ASD is a complex disorder that sometimes occurs along with other illnesses or learning disorders, the comprehensive evaluation may include brain imaging and gene tests, along with in-depth memory, problem-solving, and language testing. Children with any delayed development should also get a hearing test as part of the comprehensive evaluation.

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What are some other conditions that children with ASD may have?

Sensory Problems
Children with autism spectrum disorder (ASD) either overreact or underreact to certain sights, sounds, smells, textures, and tastes. For example, some may:

  • Dislike or show discomfort from a light touch or the feel of clothes on their skin
  • Experience pain from certain sounds, like a vacuum cleaner, a ringing telephone, or a sudden storm; sometimes they will cover their ears and scream
  • Have no reaction to intense cold or pain.

Researchers are trying to determine if these unusual reactions are related to differences in integrating multiple types of information from the senses.

Sleep Problems
Children with ASD tend to have problems falling asleep or staying asleep, or have other sleep problems. These problems make it harder for them to pay attention, reduce their ability to function, and lead to poor behavior. Fortunately, sleep problems can often be treated with changes in behavior, such as following a sleep schedule or creating a bedtime routine.

Some children may sleep better using medications such as melatonin, which is a hormone that helps regulate the body's sleep-wake cycle. Like any medication, melatonin can have unwanted side effects. Doctors can give guidance about possible risks and benefits before giving a child melatonin. Treating sleep problems in children with ASD may improve the child's overall behavior and functioning, as well as relieve family stress.

Intellectual Disability
Many children with ASD have some degree of intellectual disability. When tested, some areas of ability may be normal, while others—especially cognitive (thinking) and language abilities—may be relatively weak. For example, a child with ASD may do well on tasks related to sight (such as putting a puzzle together) but may not do as well on language-based problem-solving tasks. Some children with ASD (such as those formerly diagnosed with Asperger’s syndrome) often have average or above-average language skills and do not show delays in cognitive ability or speech.

One in four children with ASD has seizures, often starting either in early childhood or during the teen years.  An electroencephalogram (EEG), a nonsurgical test that records electrical activity in the brain, can help confirm whether a child is having seizures. However, some children with ASD have abnormal EEGs even if they are not having seizures.

Seizures can be treated with medicines called anticonvulsants. Some seizure medicines affect behavior; changes in behavior should be closely watched in children with ASD. In most cases, a doctor will use the lowest dose of medicine that works for the child. Anticonvulsants usually reduce the number of seizures but may not prevent all of them.
For more information about medications, see the NIMH online booklet, "Mental Health Medications". None of these medications have been approved by the FDA to specifically treat symptoms of ASD.

Gastrointestinal Problems
Some parents of children with ASD report that their child has frequent gastrointestinal (GI) or digestion problems, including stomach pain, diarrhea, constipation, acid reflux, vomiting, or bloating. Food allergies may also cause problems for children with ASD. (See Timely Topic: Food Allergies for more information.)

It's unclear whether children with ASD are more likely to have GI problems than typically developing children. If a child has GI problems, a doctor who specializes in GI problems, called a gastroenterologist, can help find the cause and suggest appropriate treatment.

Some studies suggest that children with ASD may not have underlying GI problems, but that their behavior may create GI symptoms—for example, a child who insists on eating only certain foods may not get enough fiber or fluids in his or her diet, which leads to constipation.

While some children may benefit from limiting certain foods, there is no strong evidence that these special diets reduce ASD symptoms. Prior to trying a special diet, a doctor or a nutrition expert should make sure a child's nutritional needs are being met.

Co-occurring Mental Disorders
Children with ASD are at higher risk of developing mental disorders such as anxiety disorders, attention deficit hyperactivity disorder (ADHD), or depression. Managing these co-occurring conditions with medications or behavioral therapy, which teaches children how to control their behavior, can reduce symptoms that appear to worsen a child's ASD symptoms. Controlling these conditions will allow children with ASD to focus more on managing the ASD.

Related Disorders
Rett syndrome is another developmental disorder which includes a regression in development. Rett syndrome mostly affects girls and a mutation in the sequence of a single gene is linked to most cases of Rett syndrome.  Rett syndrome is rare, it affects only 1 of every 10,000 to 22,000 girls.  In general, children with Rett syndrome develop normally for 6–18 months before regression and autism-like symptoms begin to appear. Children with Rett syndrome may also have difficulties with coordination, movement, and speech. Physical, occupational, and speech therapy can help, but no specific treatment for Rett syndrome is available yet.

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While there's no proven cure yet for autism spectrum disorder (ASD), treating ASD early, using school-based programs, and getting proper medical care can greatly reduce ASD symptoms and increase a child's ability to grow, learn new skills and function better in daily life.

Early Intervention
Research has shown that intensive behavioral therapy during the toddler or preschool years can significantly improve cognitive and language skills in young children with ASD. There is no single best treatment for all children with ASD, but the American Academy of Pediatrics recently noted common features of effective early intervention programs. These include:

  • Starting as soon as a child has been diagnosed with ASD
  • Providing focused and challenging learning activities at the proper developmental level for the child for at least 25 hours per week and 12 months per year
  • Having small classes to allow each child to have one-on-one time with the therapist or teacher and small group learning activities
  • Having special training for parents and family
  • Encouraging activities that include typically developing children, as long as such activities help meet a specific learning goal
  • Measuring and recording each child's progress and adjusting the intervention program as needed
  • Providing a high degree of structure, routine, and visual cues, such as posted activity schedules and clearly defined boundaries, to reduce distractions
  • Guiding the child in adapting learned skills to new situations and settings and maintaining learned skills
  • Using a curriculum that focuses on
    • Language and communication
    • Social skills, such as joint attention (looking at other people to draw attention to something interesting and share in experiencing it)
    • Self-help and daily living skills, such as dressing and grooming
    • Research-based methods to reduce challenging behaviors, such as aggression and tantrums
    • Cognitive skills, such as pretend play or seeing someone else's point of view
    • Typical school-readiness skills, such as letter recognition and counting.

One type of a widely accepted treatment is applied behavior analysis (ABA). The goals of ABA are to shape and reinforce new behaviors, such as learning to speak and play, and reduce undesirable ones. ABA, which can involve intensive, one-on-one child-teacher interaction for up to 40 hours a week, has inspired the development of other, similar interventions that aim to help those with ASD reach their full potential. ABA-based interventions include:

  • Verbal Behavior—focuses on teaching language using a sequenced curriculum that guides children from simple verbal behaviors (echoing) to more functional communication skills through techniques such as errorless teaching and prompting
  • Pivotal Response Training—aims at identifying pivotal skills, such as initiation and self-management, that affect a broad range of behavioral responses. This intervention incorporates parent and family education aimed at providing skills that enable the child to function in inclusive settings.

For children younger than age 3, these interventions usually take place at home or in a child care center. Because parents are a child's earliest teachers, more programs are beginning to train parents to continue the therapy at home.

Students with ASD may benefit from some type of social skills training program. While these programs need more research, they generally seek to increase and improve skills necessary for creating positive social interactions and avoiding negative responses. For example, Children's Friendship Training focuses on improving children's conversation and interaction skills and teaches them how to make friends, be a good sport, and respond appropriately to teasing.

Working with a Child's School
One can start by speaking with the child's teacher, school counselor, or the school's student support team to begin an evaluation. Each state has a Parent Training and Information Center and a Protection and Advocacy Agency that can help get an evaluation. A team of professionals conducts the evaluation using a variety of tools and measures. The evaluation will look at all areas related to a child's abilities and needs.

Once a child has been evaluated, there are several options, depending on the specific needs. If a child needs special education services and is eligible under the Individuals with Disabilities Education Act (IDEA), the school district (or the government agency administering the program) must develop an individualized education plan, or IEP specifically for your child within 30 days.

IDEA provides free screenings and early intervention services to children from birth to age 3. IDEA also provides special education and related services from ages 3 to 21. Information is available from the U.S. Department of Education.

If a child is not eligible for special education services—not all children with ASD are eligible—he or she can still get free public education suited to his or her needs, which is available to all public-school children with disabilities under Section 504 of the Rehabilitation Act of 1973, regardless of the type or severity of the disability.

The U.S. Department of Education's Office for Civil Rights enforces Section 504 in programs and activities that receive Federal education funds. More information on Section 504 is available on the Department of Education website .

More information about U.S. Department of Education programs for children with disabilities is available on their website .
During middle and high school years, the child's teachers will begin to discuss practical issues such as work, living away from a parent or caregiver's home, and hobbies. These lessons should include gaining work experience, using public transportation, and learning skills that will be important in community living.

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Some medications can help reduce symptoms that cause problems for a child in school or at home. Many other FDA approved medications may be prescribed off-label, meaning they have not been approved by the U.S. Food and Drug Administration (FDA) for a certain use or for certain people.

Doctors may prescribe medications off-label if they have been approved to treat other disorders that have similar symptoms to ASD, or if they have been effective in treating adults or older children with ASD. Doctors prescribe medications off-label to try to help the youngest patients, but more research is needed to be sure that these medicines are safe and effective for children and teens with ASD.

At this time, the only medications approved by the FDA to treat aspects of ASD are the antipsychotics risperidone (Risperdal) and aripripazole (Abilify). These medications can help reduce irritability—meaning aggression, self-harming acts, or temper tantrums—in children ages 5 to 16 who have ASD.

Some medications that may be prescribed off-label for children with ASD include the following:

  • Antipsychotic medications, Antidepressant medications, such as fluoxetine (Prozac) or sertraline (Zoloft)
  • Stimulant medications, such as methylphenidate (Ritalin).

All medications carry a risk of side effects. For details on the side effects of common psychiatric medications, see the NIMH website on "Mental Health Medications."

FDA Warning about Antidepressants
The FDA warning says that patients of all ages taking antidepressants should be watched closely, especially during the first few weeks of treatment. Possible side effects to look for are depression that gets worse, suicidal thinking or behavior, or any unusual changes in behavior such as trouble sleeping, agitation, or withdrawal from normal social situations. Families and caregivers should report any changes to the prescribing doctor. The latest information is available on the FDA website .

It is advisable to work with a doctor who has experience treating children with ASD because a child with ASD may not respond in the same way to medications as typically developing children. The doctor will usually start a child on the lowest dose that helps control problem symptoms. Parents or caregivers should ask the doctor about any side effects of the medication and keep a record of how the child reacts to the medication. The doctor should regularly check your child's response to the treatment.

Living with ASD
After a child is diagnosed with autism spectrum disorder (ASD), a parent or other caregiver may feel unprepared or unable to provide the child with the necessary care and education. Know that there are many treatment options, social services and programs, and other resources that can help.

Some tips that can help a parent and a child are:

  • Keep a record of conversations, meetings with health care providers and teachers, and other sources of information. This will help keep track of the different treatment options and decide which would help the child most.
  • Keep a record of the doctors' reports and the child's evaluation. This information may help a child qualify for special programs.
  • Contact the local health department or autism advocacy groups to learn about the special programs available in a particular state and local community.
  • Talk with the child's pediatrician, school system, or an autism support group to find an autism expert in your area who can help develop an intervention plan and find other local resources.

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Understanding Teens with ASD
The teen years can be a time of stress and confusion for any child, including teenagers with autism spectrum disorder (ASD).
During the teenage years, adolescents become more aware of other people and their relationships with them. While most teenagers are concerned with acne, popularity, grades, and dates, teens with ASD may become painfully aware that they are different from their peers.

For some, this awareness may encourage them to learn new behaviors and try to improve their social skills. For others, hurt feelings and problems connecting with others may lead to depression, anxiety, or other mental disorders. One way that some teens with ASD may express the tension and confusion that can occur during adolescence is through increased autistic or aggressive behavior.

Teens with ASD will also need support to help them understand the physical changes and sexual maturation they experience during adolescence.

If a teen seems to have trouble coping, talk with his or her doctor about possible co-occurring mental disorders and what can be done. Behavioral therapies and medications often help.

Preparing for a Child's Transition to Adulthood
The public schools' responsibility for providing services ends when a child with ASD reaches the age of 22. At that time, some families may struggle to find jobs to match their adult child's needs. If a family cannot continue caring for an adult child at home, a parent may need to look for other living arrangements.

Long before a child finishes school, parents should search for the best programs and facilities for young adults with ASD. If one knows other parents of adults with ASD, ask them about the services available in the community. Local support and advocacy groups may be able to help find programs and services that a child is eligible to receive as an adult.

Another important part of this transition is teaching youth with ASD to self-advocate. This means that they start to take on more responsibility for their education, employment, health care, and living arrangements. Adults with ASD or other disabilities must self-advocate for their rights under the Americans with Disabilities Act at work, in higher education, in the community, and elsewhere.

Living Arrangements for Adults with ASD
There are many options for adults living with ASD. Helping an adult child choose the right one will largely depend on what is available in the state and local community, as well as a child's skills and symptoms. Below are some examples of living arrangements to consider:

  • Independent living. Some adults with ASD are able to live on their own. Others can live in their own home or apartment if they get help dealing with major issues, such as managing personal finances, obtaining necessary health care, and interacting with government or social service agencies. Family members, professional agencies, or other types of providers can offer this assistance.
  • Living at home. Government funds are available for families who choose to have their adult child with ASD live at home. These programs include Supplemental Security Income, Social Security Disability Insurance, and Medicaid waivers. Information about these programs and others is available from the Social Security Administration (SSA). Make an appointment with the local SSA office to find out about appropriate programs.
  • Other home alternatives. Some families open their homes to provide long-term care to adults with disabilities who are not related to them. If the home teaches self-care and housekeeping skills and arranges leisure activities, it is called a "skill-development" home.
  • Supervised group living. People with disabilities often live in group homes or apartments staffed by professionals who help with basic needs. These needs often include meal preparation, housekeeping, and personal care. People who are more independent may be able to live in a home or apartment where staff only visit a few times a week. Such residents generally prepare their own meals, go to work, and conduct other daily activities on their own.
  • Long-term care facilities. This alternative is available for those with ASD who need intensive, constant supervision.

The information provided above is a condensed version of: A Parent’s Guide to Autism Spectrum Disorder, available at:

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NIMH - National Institute of Mental Health: Autism Spectrum Disorder

CDC - Centers for Disease Control and Prevention: Autism Spectrum Disorder (ASD)