Autism

A developmental disorder that varies widely in severity, autism is marked by communication problems, social difficulties and, often, repetitive behaviors. The cause appears to be growth dysregulation, and early treatment can produce big gains in function.

Definition

Autism is a complex developmental disorder that affects the brain's normal development of social and communication skills. Common features of autism include impaired social interactions, impaired verbal and nonverbal communication, problems processing information from the senses, and restricted and repetitive patterns of behavior.

People with autism—the core form of the autism spectrum disorders (ASD)—tend to appear indifferent and remote and are unable to form emotional bonds with others. In addition, they will often have unusual responses to sensory experiences. Each of these symptoms runs the gamut from mild to severe. They will present differently in each individual child. For instance, a child may have little trouble learning to read but exhibit extremely poor social interaction. Each child will display social, behavioral, and communication patterns that are individual but fit into the overall diagnosis of ASD.

Children with autism do not follow the typical patterns of child development. In some, signs of future problems may be apparent from birth. Other children develop typically at first, but between the ages of 18 and 36 months, their development stagnates. Parents may notice that they begin to reject social contact, act strangely, and even lose language and social skills that they have already acquired. In other cases, there is a plateau or leveling of progress, and the difference between the child with autism and other children the same age becomes more noticeable.

A recent study of a U.S. metropolitan area estimated that 3.4 of every 1,000 children ages 3 to 10 had autism.

Autism is found in every country and region of the world and in families of all racial, ethnic, religious, and economic backgrounds. This wide range of prevalence points to a need for earlier and more accurate screening for the symptoms of ASD. The earlier the disorder is diagnosed, the sooner the child can be helped through treatment interventions. Pediatricians, family physicians, day-care providers, teachers, and parents may initially dismiss signs of ASD, optimistically thinking the child is just a little slow and will catch up. Although early intervention has a dramatic impact on reducing symptoms and increasing a child's ability to grow and learn new skills, it is estimated that only 50 percent of children are diagnosed before kindergarten.

Symptoms

Social Deficits

Most children with autism have tremendous difficulty engaging in everyday human interaction, and even in infancy—the stage in which most babies tend to want to touch and explore other human beings—they keep to themselves and avoid eye contact. They may resist basic forms of affection and may not show anger or pleasure when the parent leaves or returns. Research has suggested that although children with ASD are attached to their parents, their expression of this attachment is unusual and difficult to read. To parents, it may seem as if their child is not attached at all. Parents who looked forward to the joys of cuddling, teaching, and playing with their child may feel crushed by this lack of the expected and typical attachment behavior.

Children with autism have difficulty understanding unspoken social cues.

Subtle social cues—whether a smile, a wink, or a grimace—may have little meaning. To a child who misses these cues, "come here" always means the same thing, whether the speaker is smiling and extending her arms for a hug or frowning and planting her fists on her hips. Without the ability to interpret gestures and facial expressions, the social world may seem bewildering.

An autistic person may also lack ability to understand things from another's perspective, making them unable to comprehend or predict other people's responses to their own actions.

Some people with autism also might have difficulty regulating their emotions; they may tend to be physically aggressive or prone to loss of control, particularly when they are frustrated or in an overwhelming environment. They may break things, pull their hair, and hurt themselves or others.

Language Deficits

Research shows that while some infants babble during their first six months, about half of the children diagnosed with autism remain mute throughout their lives. Those who are not mute may develop language skills as late as ages 5 to 9, whereas most children without autism can put together phrases and follow simple directions by age 2. Those who speak might repeat the same phrase over and over, only use single words, or be unable to combine words into logical sentences.

Some autistic children are only able to repeat what they have heard, a condition called echolalia. Children without autism also have this tendency, but the phase usually ends by the time they are 3.

Some children who are only mildly affected exhibit slight delays in language or even seem to have precocious language skills and unusually large vocabularies; however, they have great difficulty sustaining a conversation. The give and take of normal conversation is hard for them, although they often carry on a monologue on a favorite subject, giving no one else an opportunity to comment. Another frequent difficulty is the inability to understand body language, tone of voice, or phrases of speech.

People with autism tend to confuse pronouns, so the words "my," "I," and "you" all mean the same thing. If an autistic child's father asks, "What color is my shirt?" the child might respond with the color of his own shirt.

Interpreting body language of a child with autism can be difficult, as the gestures and tone of voice rarely match what the child is saying or indicate what the child is feeling. A voice that is either high-pitched and sing-song or flat and robotlike is common among children with ASD.

Without meaningful gestures or the language to make simple requests, people with ASD are at a loss to let others know what they need. As a result, they may simply grab what they want or scream. Until they are taught better ways to express their needs, ASD children do whatever they can to get through to others. As people with ASD grow up, they can become increasingly aware of their difficulties in understanding others and in being understood. As a result, they may become anxious or depressed.

Repetitive Behaviors

Many people with ASD walk on their toes or flail their arms and suddenly freeze their position. Experts call such behaviors stereotypes or self-stimulation.

People with autism, especially children, need and demand absolute consistency in their environment, many engaging in daily rituals at exactly the same time in the same place. They may get deeply angered if a cup is not in the place they left it or a pillow is on a different part of the sofa. As children, they might spend hours lining up their toy cars and trains in a certain way, rather than using them for pretend play. If someone accidentally moves one of the toys, the child may become tremendously upset.

Repetitive behavior sometimes takes the form of a persistent, intense preoccupation. For example, the child might be obsessed with learning all about vacuum cleaners, train schedules, or lighthouses. Often there is great interest in numbers, symbols, or science topics. A child's ability to play is limited by these compulsive behaviors. For the child with ASD there is little imaginative or pretend play. They don't imitate the actions of others, and they prefer solitary or ritualistic play.

Problems That May Accompany ASD

Sensory Perception Issues

Autistic children tend to be incapable of accurately taking in sensory perception or merging the stimuli into a coherent picture, leading to a baffling experience of the world. Many children with autism are highly attuned or even painfully sensitive to certain sounds, textures, tastes, or smells. Some children find the smell of a certain food cooking so distracting that it becomes their entire focus. For others, a gentle pat on the head may be terrifying. Some sounds—a vacuum cleaner, a ringing telephone, a sudden storm, even the sound of waves lapping the shoreline—will cause these children to cover their ears and scream.

The brain of an autistic child seems unable to balance the senses appropriately. This can cause some children to be oblivious to extreme cold; others may fall and break an arm yet never cry. Another may bash his head against a wall and not wince, but a light touch will make him scream with alarm. In some people, the senses are scrambled: A child may cover her ears to avoiding hearing a certain color that she experiences as sound.

Mental Retardation

Many children with ASD have some degree of mental impairment. When tested, some areas of ability may be normal, while others may be especially weak. For example, a child with ASD may do well on the parts of the test that measure visual skills but earn low scores on the language subtests.

Seizures

About one-fourth of children with autism develop seizures either in early childhood or adolescence. These can range from brief blackouts to full-blown body convulsions. In most cases, seizures can be controlled with medication.

Fragile X

Fragile X syndrome (the most commonly inherited form of mental retardation, named for a defective piece of the X chromosome that appears pinched and fragile under a microscope) is found in 2 percent to 5 percent of people with autism. People who inherit this genetic code are more likely to have mental retardation and many symptoms of autism along with unusual physical features that are not typical of autism. It is important to have a child with ASD checked for fragile X, especially if the parents are considering having another child. For unknown reasons, if a child with ASD also has fragile X, there is a 50 percent chance that boys born to the same parents will also have the syndrome. Other members of the family who may be contemplating having a child may wish to be checked for the syndrome.

Tuberous Sclerosis

There is a relationship between autism and tuberous sclerosis, a genetic condition that causes abnormal tissue growth in the brain and problems in other organs. While tuberous sclerosis occurs less than once in 10,000 births, about a fourth of those affected are also autistic. Scientists are exploring genetic conditions such as fragile X and tuberous sclerosis to see why they so often coincide with autism.

Diagnosing Autism

For a diagnosis of autism, problems in at least one of the areas of communication, socialization, or restricted behavior must be present before the age of 3. The diagnosis requires a two-stage process. The first stage involves developmental screening during "well child" checkups; the second stage entails a comprehensive evaluation by a multidisciplinary team.

Parents may notice their baby seems different from birth, unresponsive to toys and people or focusing intently on one item for oddly long periods. Yet autistic signs can also turn up in a toddler who had previously seemed normal: A generally healthy, responsive baby suddenly becomes violent or withdrawn. Years may pass before a parent seeks a diagnosis, wishing instead to believe that everything is all right, which only delays appropriate treatment.

Reviewing family videotapes, photos, and baby albums can help parents remember when each behavior was first noticed and when the child reached certain developmental milestones.

Several screening instruments have been developed to quickly gather information about a child's social and communicative development within medical settings. Among them are the Checklist of Autism in Toddlers (CHAT), the modified Checklist for Autism in Toddlers (M-CHAT), the Screening Tool for Autism in Two-Year-Olds (STAT), and the Social Communication Questionnaire (SCQ; for children 4 years of age and older). Some screening instruments rely solely on parent responses to a questionnaire, and some rely on a combination of parent reports and observation. Key items on these instruments that appear to differentiate children with autism from other groups before the age of 2 include pointing and pretend play.

A doctor may also consider other conditions with the same symptoms as autism, such as Rett's disorder or Asperger's syndrome. Rett's disorder is a progressive brain disease that only affects girls but, similar to autism, produces repetitive hand movements and leads to loss of language and social skills. Children with Asperger's syndrome have repetitive behaviors, severe social problems, and clumsy movements, yet their language and intelligence are usually intact.

During the last few years, screening instruments have been devised to screen for Asperger's syndrome and higher-functioning autism. The Autism Spectrum Screening Questionnaire (ASSQ), the Australian Scale for Asperger's Syndrome, and the Childhood Asperger Syndrome Test (CAST), are some of the instruments that are reliable for identification of school-age children with Asperger's syndrome or higher-functioning autism. These tools concentrate on social and behavioral impairments in children without significant language delay.

In order to rule in or rule out ASD or other developmental disorders, the second phase of diagnosis must be comprehensive, including neurological and genetic assessments along with in-depth cognitive and language testing. These include the Autism Diagnosis Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS-G). The ADI-R is a structured interview that contains over 100 items and is conducted with a caregiver. It concentrates on four main factors—communication, social interaction, repetitive behaviors, and age-of-onset symptoms. The ADOS-G is an observational measure used to press for socio-communicative behaviors that are often delayed, abnormal, or absent in children with ASD.

Another instrument often used by professionals is the Childhood Autism Rating Scale (CARS). It aids in evaluating the child's body movements, adaptation to change, listening response, verbal communication, and relationship to people. It is suitable for use with children over 2 years of age. The examiner observes the child and also obtains relevant information from the parents. The child's behavior is rated on a scale based on deviation from the typical behavior of children of the same age.

Two other tests that should be used to assess any child with a developmental delay: A formal audiologic hearing evaluation should be administered to determined if there is an actual hearing loss, and a lead screening should be conducted. Children with an autistic disorder usually have elevated blood lead levels.

Receiving a diagnosis of autism can be devastating, but be sure to ask questions of the evaluation team and get recommendations for further steps as well as the names of professionals who can answer other questions that might come up.

Causes

Autism is a physical disorder linked to abnormal biology and chemistry in the brain. The exact causes of these abnormalities remain unknown, but this is a very active area of research. Genetic factors seem to be important. For example, identical twins are much more likely than fraternal twins or siblings to both have autism. Similarly, language abnormalities are more common in relatives of autistic children. Chromosomal abnormalities and other neurological problems are also more common in families with autism.

Researchers supported by NIMH and other National Institute of Health (NIH) institutes are studying how an autistic brain differs from a normal brain. Some researchers are investigating potential defects that occur during initial brain development; others are looking for defects in the brains of people already diagnosed with autism.

Recent neuroimaging studies have shown that a contributing cause for autism may be abnormal brain development beginning in the infant's first months. This "growth dysregulation" theory holds that the anatomical abnormalities seen in autism are caused by genetic defects in brain-growth factors. It is possible that sudden, rapid head growth in an infant may be an early warning signal that will lead to early diagnosis and effective biological intervention or possible prevention of autism.

Postmortem and magnetic resonance imaging (MRI) studies have shown that many major brain structures are implicated in autism. This includes the cerebellum, cerebral cortex, limbic system, corpus callosum, basal ganglia, and brain stem. Other research is focusing on the role of neurotransmitters such as serotonin, dopamine, and epinephrine.

Treatments

There is no single best treatment package for all children with ASD. One point that most professionals agree on is that early intervention is important; another is that most individuals with ASD respond well to highly structured, specialized programs. Treatment may also include medication as monitored by a medical professional.

Before you make decisions on your child's treatment, you will want to gather information about the various options available. Learn as much as you can, look at all the options, and make your decision on your child's treatment based on your child's needs. You may want to visit public schools in your area to see the type of program they offer to special-needs children. To select the right treatment for your child, consider how successful the program has been for other children, whether staff members have training and experience in working with autism, how the activities are organized, how much attention each child receives, and whether the program enables the parent to continue therapy at home.

Among the many methods available for treatment and education of people with autism, applied behavior analysis (ABA) has become widely accepted as an effective treatment. Mental Health: A Report of the Surgeon General states, "Thirty years of research demonstrated the efficacy of applied behavioral methods in reducing inappropriate behavior and in increasing communication, learning, and appropriate social behavior." The goal of behavioral management is to reinforce desirable behaviors and reduce undesirable ones.

An effective treatment program will build on the child's interests, offer a predictable schedule, teach tasks as a series of simple steps, actively engage the child's attention in highly structured activities, and provide regular reinforcement of behavior. Parental involvement has emerged as a major factor in treatment success. Parents work with teachers and therapists to identify the behaviors to be changed and the skills to be taught. Recognizing that parents are the child's earliest teachers, more programs are beginning to train parents to continue the therapy at home.

As soon as a child's disability has been identified, instruction should begin. Effective programs will teach early communication and social interaction skills. In children younger than 3, appropriate interventions usually take place in the home or a child-care center. These interventions target specific deficits in learning, language, imitation, attention, motivation, compliance, and initiative of interaction. Included are behavioral methods, communication, and occupational and physical therapy along with social-play interventions. Children older than 3 usually have school-based individualized special education. The child may be in a segregated class with other autistic children or in an integrated class with children without disabilities for at least part of the day. See the educational section below for more information.

Before spending time and money and possibly delaying progress, the family of an autistic child should evaluate the findings of objective reviewers. Following are some of the approaches that have not been shown to be effective in treating the majority of children with autism:

Facilitated communication: The theory is that by supporting a nonverbal child's arms and fingers so that he can type on a keyboard, the child will be able to type out his inner thoughts. Several scientific studies prove that the typed messages actually reflect the thoughts of the person providing the support.

Holding therapy: The theory is that the parents should hug the child for long periods of time, even if the child resists, to encourage a bond. There is no scientific evidence to support that this creates a bond between parent and child.

Auditory integration training: In this therapy, a child listens to a variety of sounds in order to improve language comprehension. This method is supposed to help people with autism receive more balanced sensory input from their environment. When tested using scientific procedures, the method was shown to be no more effective than listening to music.

Dolman/Delcato method: This treatment has people crawl and move as they did at each stage of early development, in an attempt to learn missing skills. There is no scientific support for this method.

Medications

Scientists have found that while no medication can correct the impairments underlining autism, medications are often used to treat behavioral problems, such as aggression, self-injurious behavior, and severe tantrums, that keep the person with ASD from functioning more effectively at home or school. The medications used are those that have been developed to treat similar symptoms in other disorders, such as OCD and depression.

A child with ASD may not respond to medications in the same way as typically developing children. It is important that parents work with a doctor who has experience with children with autism. A child should be monitored closely while taking a medication. The doctor will prescribe the lowest dose possible to be effective. Ask the doctor about any side effects the medication may have and keep a record of how your child responds to the medication. It will be helpful to read the patient insert that comes with your child's medication. Some people keep the patient inserts in a small notebook to be used as a reference. This is most useful when several medications are prescribed.

Anxiety and depression. The selective serotonin reuptake inhibitors (SSRIs) are the medications most often prescribed for symptoms of anxiety, depression, and/or obsessive-compulsive disorder (OCD). Only one of the SSRIs, fluoxetine (Prozac®), has been approved by the FDA for both OCD and depression in children age 7 and older. Three that have been approved for OCD are fluvoxamine (Luvox®), age 8 and older; sertraline (Zoloft®), age 6 and older; and clomipramine (Anafranil®), age 10 and older (Newschaffer, 2003). Treatment with these medications can be associated with decreased frequency of repetitive, ritualistic behavior and improvements in eye contact and social contacts. The FDA is studying and analyzing data to better understand how to use the SSRIs safely, effectively, and at the lowest dose possible.

Please note that a "black box" warning was issued in 2004 (and modified in 2007 to include young adults up to 25) for all antidepressant drugs by the Food and Drug Administration (FDA) after a thorough review of data. The warning emphasizes that children, adolescents, and young adults taking antidepressants should be closely monitored, especially during the initial weeks of treatment, for worsening depression, suicidal thinking or behavior, or any unusual changes in behavior such as sleeplessness, agitation, or withdrawal from normal social situations.

Behavioral problems. Antipsychotic medications have been used to treat severe behavioral problems. These medications work by reducing the activity of the neurotransmitter dopamine in the brain. Among the older, typical antipsychotics, such as haloperidol (Haldol®), thioridazine, fluphenazine, and chlorpromazine, haloperidol was found in more than one study to be more effective than a placebo in treating serious behavioral problems. However, haloperidol, while helpful for reducing symptoms of aggression, can also have adverse side effects, such as sedation, muscle stiffness, and abnormal movements.

A study on atypical antipsychotics conducted by the NIMH-supported Research Units on Pediatric Psychopharmacology (RUPP) Autism Network showed that risperidone was effective and well tolerated for the treatment of severe behavioral problems in children with autism (RUPP, 2002). The most common side effects were increased appetite, weight gain, and sedation. On October 6, 2006, the U.S. Food and Drug Administration (FDA) approved risperidone (Risperdal®) for the symptomatic treatment of irritability in autistic children and adolescents, ages 5 to 16. The approval is the first for the use of a drug to treat behaviors such as irritability, aggression, deliberate self-injury, and temper tantrums, all associated with autism in children. Further long-term studies are needed to determine any long-term side effects. Other atypical antipsychotics that have been studied recently with encouraging results are olanzapine (Zyprexa®) and ziprasidone (Geodon®) which has not been associated with significant weight gain.

Seizures. Seizures are found in one in four persons with ASD, most often in those who have low IQ or are mute. They are treated with one or more anticonvulsants, including such medications as carbamazepine (Tegretol®), lamotrigine (Lamictal®), topiramate (Topamax®), and valproic acid (Depakote®). The level of the medication in the blood should be monitored carefully and adjusted so that the lowest effective amount possible is used. Although medication usually reduces the number of seizures, it cannot always eliminate them.

Inattention and hyperactivity. Stimulant medications such as methylphenidate (Ritalin®), used safely and effectively in persons with attention-deficit/hyperactivity disorder, have also been prescribed for children with autism. These medications may decrease impulsivity and hyperactivity in some children, especially those higher functioning children.

Several other medications have been used to treat ASD symptoms; among them are other antidepressants, naltrexone, lithium, and some of the benzodiazepines such as diazepam (Valium®) and lorazepam (Ativan®). The safety and efficacy of these medications in children with autism has not been proved. Since people may respond differently to different medications, your child's unique history and behavior will help your doctor decide which medication might be most beneficial.

Options in Education

For every child eligible for special programs, each state guarantees special education and related services. The Individuals with Disabilities Education Act (IDEA) is a federally mandated program that assures a free and appropriate public education for children with diagnosed learning deficits. Usually children are placed in public schools and the school district pays for all necessary services. These will include, as needed, services by a speech therapist, occupational therapist, school psychologist, social worker, school nurse, or aide.

By law, public schools must prepare and carry out a set of instruction goals, or specific skills, for every child in a special education program. The list of skills is known as the child's Individualized Education Program (IEP). The IEP is an agreement between the school and the family on the child's goals. When your child's IEP is developed, you will be asked to attend the meeting. There will be several people at this meeting, including a special-education teacher, a representative of the public schools who is knowledgeable about the program, other individuals invited by the school or by you (you may want to bring a relative, a child-care provider, or a supportive close friend who knows your child well). Parents play an important part in creating the program, as they know their child and his or her needs best. Once the IEP is developed, an annual meeting is scheduled to review your child's progress and make any alterations to reflect his or her changing needs.

If your child is under 3 years of age and has special needs, he or she should be eligible for an early intervention program; these programs are available in every state. Early intervention services are provided by workers qualified to care for toddlers with disabilities and are usually in the child's home or a place familiar to the child. The services provided are written into an Individualized Family Service Plan (IFSP) that is reviewed at least once every six months. The plan will describe services that will be provided to the child but will also describe services for parents to help them in daily activities with their child and for siblings to help them adjust to having a brother or sister with ASD.

The Teen Years

Adolescence is a time of stress and confusion, even for children with no significant brain disorder, and autistic children carry with them special challenges. Like all children, they need help in dealing with their budding sexuality. While some behaviors improve in the teenage years, some get worse. Increased autistic or aggressive behavior may be one way some teens express their newfound tension and confusion.

The teenage years are also a time when children become more socially sensitive and aware. At the age that most teenagers are concerned with acne, popularity, grades and dates, teens with autism may become painfully aware that they are different from their peers. They may notice that they lack friends and, unlike their schoolmates, they aren't dating or planning for a career. For some, the sadness that comes with such realization urges them to learn new behaviors.

Autism in Adulthood

A few cities are exploring ways to help autistic people hold meaningful jobs and live and work within the wider community. Innovative programs enable the autistic adult to live and work in mainstream society, rather than be limited to a segregated environment.

Nevertheless, communication and social problems often cause difficulties in many areas of life. Adults with ASD will continue to need encouragement and moral support in their struggle for an independent life.

Many people with ASD are capable of employment in sheltered workshops under the supervision of managers trained in working with persons with disabilities. A nurturing environment at home, at school, and later in job training and at work, helps persons with ASD continue to learn and to develop throughout their lives.

Living Arrangements for the Adult with an Autism Spectrum Disorder

Independent living. Some adults with ASD are able to live entirely on their own. Others can live semi-independently in their own home if they have assistance with solving major problems, such as personal finances or dealing with the government agencies that provide services to persons with disabilities. This assistance can be provided by family, a professional agency, or another type of provider.

Living at home. Government funds are available for families that choose to have their adult child with ASD live at home. These programs include Supplemental Security Income (SSI), Social Security Disability Insurance (SSDI), Medicaid waivers, and others. Information about these programs is available from the Social Security Administration (SSA). An appointment with a local SSA office is a good first step to take in understanding the programs for which the young adult is eligible.

Foster homes and skill-development homes. Some families open their homes to provide long-term care to unrelated adults with disabilities. If the home teaches self-care and housekeeping skills and arranges leisure activities, it is called a "skill-development" home.

Supervised group living. Persons with disabilities frequently live in group homes or apartments staffed by professionals who help the individuals with basic needs. These often include meal preparation, housekeeping, and personal-care needs. Higher-functioning persons may be able to live in a home or apartment where staff only visit a few times a week. These persons generally prepare their own meals, go to work, and conduct other daily activities on their own.

Institutions. Although the trend in recent decades has been to avoid placing persons with disabilities into long-term-care institutions, this alternative is still available for persons with ASD who need intensive, constant supervision. Unlike many of the institutions of past eras, today's facilities view residents as individuals with human needs and offer opportunities for recreation and simple but meaningful work.

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Last reviewed 11/24/2014