Autism

What is autism?

Autism is a developmental disorder that is characterized by impaired development in communication, social interaction, and behavior. Autism is classified as a Pervasive Developmental Disorder (PDD), which is part of a broad spectrum of developmental disorders affecting young children and adults--the Autistic Spectrum Disorders (ASD). The range of these disorders varies from severely impaired individuals with autism to other individuals who have abnormalities of social interaction but normal intelligence--Asperger's syndrome. The ways in which autism is exhibited can differ greatly. Additionally, autism can be found in association with other disorders such as mental retardation and certain medical conditions. The degree of autism can range from mild to severe. Mildly affected individuals may appear very close to normal. Severely afflicted individuals may have an extreme intellectual disability and unable to function in almost any setting.

It is estimated that roughly three to six out of every 1,000 children in the United States have autism, and the number of diagnosed cases is rising. However, it is not clear whether this is due to better detection and reporting of autism, a real increase in the number of cases, or both.

In the past, autism has been confused with childhood schizophrenia or childhood psychosis, and may have been misunderstood as schizotypal personality disorder in some adults. As additional research information about autism becomes available, the scope and definition of the condition continues to become more refined. Much of the past confusion about the disorder has been resolved.

What are the symptoms of autism?

The current Diagnosis and Statistical Manual of Mental Disorders–Fourth Edition, Treatment Revision (DSM–IV–TR) identifies three features that are associated with autism:

• impairment in social interaction,
• communication, and
• behavior.

Impairment in social interaction

First, patients with autism fail to develop normal personal interactions in virtually every setting. This means that affected persons fail to form the normal social contacts that are such an important part of human development. This impairment may be so severe that it even affects the bonding between a mother and an infant. It is important to note that, contrary to popular belief, many, if not most, autistic persons are capable of showing affection and do demonstrate affection and do bond with their mothers or other caregivers. However, the ways in which autistic individuals demonstrate affection and bonding may differ greatly from the ways in which others do so. Their limited socialization may erroneously lead parents and pediatricians away from considering the diagnosis of autism. As the child develops, interaction with others continues to be abnormal. Affected behaviors can include eye contact, facial expressions, and body postures. There is usually an inability to develop normal peer and sibling relationships and the child often seems isolated. There may be little or no joy or interest in normal age-appropriate activities. Affected children or adults do not seek out peers for play or other social interactions. In severe cases, they may not even be aware of the presence of other individuals.

Communication

Communication is usually severely impaired in autistic persons. What the individual understands (receptive language) as well as what is actually spoken by the individual (expressive language) is significantly delayed or nonexistent. Deficits in language comprehension include the inability to understand simple directions, questions, or commands. There may be an absence of dramatic or pretend play and these children may not be able to engage in simple age-appropriate childhood games such as Simon Says or Hide-and-Go-Seek. Adults may continue to engage in playing with games that are for young children.

Autistic individuals who do speak may be unable to initiate or participate in a two-way conversation (reciprocal). Frequently the way in which an autistic person speaks is perceived as unusual. Their speech may seem to lack the normal emotion and sound flat or monotonous. The sentences are often very immature: "want water" instead of "I want some water please." Those with autism often repeat words or phrases that are spoken to them. For example, you might say "look at the airplane!" and the child or adult may respond "at airplane," without any knowledge of what was said. This repetition is known as echolalia. Memorization and recitation of songs, stories, commercials, or even entire scripts is not uncommon. While many feel this is a sign of intelligence, the autistic person usually does not appear to understand any of the content in his or her speech.

Autistic persons often exhibit a variety of repetitive, abnormal behaviors. There may also be a hypersensitivity to sensory input through vision, hearing, or touch (tactile). As a result, there may be an extreme intolerance to loud noises or crowds, visual stimulation, or things that are felt. Birthday parties and other celebrations can be disastrous for some of these individuals. Tags on clothing may be perceived as painful. Sticky fingers, playing with modeling clay, eating birthday cake or other foods, or walking barefoot across the grass can be unbearable. On the other hand, there may be an underdeveloped (hyposensitivity) response to the same type of stimulation. This individual may use abnormal means to experience visual, auditory, or tactile (touch) input. This person may head bang, scratch until blood is drawn, scream instead of speaking in a normal tone, or bring everything into close visual range. He or she might also touch an object, image or other people thoroughly just to experience the sensory input.

Autistic children and adults are often tied to routine and many everyday tasks may be ritualistic. Something as simple as a bath may only be accomplished after the precise amount of water is in the tub, the temperature is exact, the same soap is in its assigned spot and even the same towel is in the same place. Any break in the routine can provoke a severe reaction in the individual and place a tremendous strain on the adult trying to work with them.

There may also be non-purposeful repetition of actions or behaviors. Persistent rocking, teeth grinding, hair or finger twirling, hand flapping and walking on tiptoe are not uncommon. Frequently, there is a preoccupation with a very limited interest or a specific plaything. A child or adult may continually play with only one type of toy. The child may line up all the dolls or cars and the adult line up their clothes or toiletries, for example, and repeatedly and systematically perform the same action on each one. Any attempt to disrupt the person may result in extreme reactions on the part of the autistic individual, including tantrums or direct physical attack. Objects that spin, open and close, or perform some other action can hold an extreme fascination. If left alone, an autistic person may sit for hours turning off and on a light switch, twirling a spinning toy, or stacking nesting objects. Some individuals can also have an inappropriate bonding to specific objects and become hysterical without that piece of string, paper clip, or wad of paper.

What causes autism?

Since autism was first added to the psychiatric literature fifty years ago, there have been numerous studies and theories about its cause. Researchers still have not reached agreement regarding its specific causes. First, it must be recognized that autism is a set of a wide variety of symptoms and may have many causes. This concept is not unusual in medicine. For instance, the set of symptoms that we perceive of as a "cold" can be caused by literally hundreds of different viruses, bacteria, and even our own immune system. Autism is, undoubtedly, a biologically-based disorder. In the past, some researchers had suggested that autism was the result of poor attachment skills on the part of the mother. This belief has caused a great deal of unnecessary pain and guilt on the part of the parents of autistic children, when in fact, the inability of the individual with autism to interact appropriately is one of the key symptoms of this developmental disorder.

In support of a biological theory of autism, several known neurological disorders are associated with autistic features. Autism is one of the symptoms of these disorders. These conditions include tuberous sclerosis (an inherited disorder), the fragile X syndrome, cerebral dysgenesis (abnormal development of the brain), Rett syndrome, and some of the inborn errors of metabolism (biochemical defects). Autism, in short, seems to be the end result or "final common pathway" of numerous disorders that affect brain development. In general, however, when clinicians make the diagnosis of autism, they are excluding the known causes of autistic behaviors. However, as the knowledge of conditions that cause autism advances, fewer and fewer cases will be thought of as being "pure" autism and more individuals will be identified as having autism due to specific causes.

There is a strong association between autism and seizures. This association works in two ways: First, many patients (20 to 30%) with autism develop seizures. Second, patients with seizures, which are probably due to other causes, may develop autistic-like behaviors. One special and often misunderstood association between autism and seizures is the Landau-Kleffner Syndrome. This syndrome is also known as acquired epileptic aphasia. Some children with epilepsy develop a sudden loss of language skills--especially receptive language (the ability to understand). Many often also develop the symptoms of autism.

These children often, but not always, have a characteristic pattern of electrical brain activity seen on EEG (electroencephalogram) during deep sleep called electrographic status epilepticus during sleep (ESES). The usual age of onset of language loss or regression is around four years of age, which makes the Landau-Kleffner syndrome distinguishable from autism on these grounds, in that autism usually is first exhibited in younger children. However, in recent years, some children (very, very few) who did not exhibit overt (observable) seizures were found to have Landau-Kleffner syndrome.

The importance of these findings is that, although rare, the Landau-Kleffner syndrome can resolve spontaneously and in some cases can be treatable with prednisone, a steroid medication related to cortisone. This association between the Landau-Kleffner syndrome and autism has led many clinicians and families to search for the typical EEG pattern (ESES) in autistic individuals. This unusual EEG pattern is seen only in deep sleep, which usually requires prolonged recordings of up to 12 hours. Many, many autistic children and adults will display some abnormalities on their sleep EEG, but probably very few have true Landau-Kleffner syndrome that will respond to treatment.

It must also be noted that prednisone, in the very high doses used to treat Landau-Kleffner syndrome, almost invariably produces side effects, which may include weight gain, high blood pressure, diabetes, growth failure, stomach ulcers, irritability, destruction of the hip joint, and susceptibility to infectious disease (suppressed immune system). While most of these side effects are reversible, some of the complications of high dose prednisone therapy can be irreversible and even fatal.

Other treatments ranging from common anticonvulsant therapy to surgery have been proposed and are being tried for Landau-Kleffner syndrome. It is difficult to evaluate the true effects of any treatment for Landau-Kleffner syndrome due to the high rate of spontaneous resolution of symptoms (remission).

Is autism genetic?

Because many different disorders can result in autism, this question is complex. Certainly, disorders such as the fragile X syndrome and tuberous sclerosis, which are both associated with autism, are inherited. There are many families with more than one autistic child where the autism is not clearly due to another cause. Recent studies have found that the gene for at least one kind of familial autism may be on chromosome 13. In some families, autism seems to be passed from generation to generation. In other families, autism is not found in prior generations, but affects multiple siblings (brothers or sisters). The results of this research makes it likely that at least one "autism gene" will be found soon.

However, the majority of individuals with autism do NOT have a strong family history, which supports the premise that environmental or a combination of environmental and genetic factors contribute to the development of autism. In this context, environmental is meant to indicate any non-genetic factor, including infections, toxins, nutrition, or others.

How is autism diagnosed?

The essential features of autism are the significantly impaired or abnormal development of communication and social interaction and the abnormally restricted repertoire of behaviors, activities, and interests. This disturbance in normal development must manifest itself prior to age three. While many parents report normal development in the first year of the child, there is actually limited opportunity to observe this, as the child is usually not brought to the attention of a practitioner until several years later in many cases. If there is a period of normal development, it cannot extend past age three.

Any person with a delay or regression (loss) of language or an abnormality of social interaction beginning prior to the age of three may be suspected of being autistic. The medical evaluation begins with a thorough medical history and physical examination. This examination should be performed by a practitioner not only familiar with autism, but with other disorders that may appear similar to or mimic the symptoms of autism. The practitioner should have particular expertise in the neurological examination of impaired individuals, as subtle findings may lead the examiner down a particular diagnostic path. For example, the presence of mild weakness or increased reflexes on one side of the body will lead the examiner to conclude that a structural abnormality in the brain is present and that an MRI examination of the brain is appropriate.

The history and physical examination will point the examiner to specific diagnostic testing to evaluate for other conditions associated with autism or developmental delay. Any child who has a language delay should have his or her hearing formally evaluated. It is not sufficient to simply determine whether or not a person being examined is able to hear. In order for normal language development to proceed, the individual must have sufficient hearing capabilities at low volumes in the high frequency range. Therefore, even if the person turns his or her head to a clap or shout, he or she may still have enough of a hearing deficit to inhibit language development.

There are two types of hearing tests; behavioral audiometry and brainstem auditory evoked responses (BAER). Behavioral audiometry is performed by a skilled clinical audiologist. The person being examined is placed in a room and his or her responses to different tones are observed. For the BAER, the individual is sedated and earphones are placed over the ears. Tones of different volumes and frequencies are played and the electrical response of the brain is monitored. If the he or she is capable, behavioral audiometry is the preferred method primarily because sedation is not required. Depending upon specific features of the examination and history, the practitioner may want to obtain blood and urine samples for specialized testing to evaluate for some of the inborn errors of metabolism and to obtain DNA for chromosomal studies and fragile X testing.

If the neurological examination is normal, there is may be no need for a brain CT ("CAT scan") or MRI scan. However, if the neurological examination is suggestive of a structural brain lesion, then a neuroimaging study, preferably an MRI, should be performed. Newer imaging procedures such as SPECT or PET scans are used primarily as research tools and have no place in the initial evaluation of the autistic individual. In very specialized instances, such as the autistic person with difficult-to-control seizures, such tests may be useful.

The evaluation of autistic persons by speech pathologists will provide not only detailed information as to the nature of the language deficits incurred by the autistic individual, but will also be the first step in formulating a specific treatment plan with respect to language. Occupational assessment may be particularly helpful in determining the day-to-day strengths and vulnerabilities of the individual with autism (for example, sensitivity to clothing and food texture) and assist those who care for the person in promoting his or her strengths and compensating for their challenges.

How is autism treated?

Misinformation about autism is very common. Claims of a cure for autism are constantly presented to families of autistic individuals. There are various treatment models found within both the educational and clinical settings. Yet, there is only one treatment approach that has prevailed over time and is effective for all persons, autistic or not. That treatment model is an educational program that is suitable to a student's developmental level of performance. For adults, that treatment model refers to a vocational program that is suitable to the individual's developmental level of functioning.

Under the Individuals with Disabilities Educational Act (IDEA) Act of 1990, students with a handicap are guaranteed an "appropriate education" in the Least Restrictive Environment (LRE), which is generally considered to be as normal an educational setting as possible. As a result of this legislation, autistic children have generally been placed in a mainstreamed classroom and pulled out for whatever supplementary services were needed. Depending on the child's needs, he or she could be placed up to 100% of the school day in a mainstreamed or a special education setting or any combination of the two.

There is an increasing trend, however, among the advocates for autistic children, to segregate these children into small, highly structured and controlled academic settings that are almost free from auditory and visual stimulation. All instruction is broken down into manageable segments. Information is presented in tiny units and the child's response is immediately sought. A classic stimulus-response approach is used to maximize learning. Each unit of information is mastered before another is presented. A fundamental behavior such as putting hands on the tabletop, for example, must be mastered before the child is required to perform any other tasks, or before more information is presented. The long-term effects of this type of treatment as well as the ability of the child to transfer this to a broader context continue to be evaluated.

Autistic individuals must be taught how to communicate and interact with others. This is not a simple task, and it involves the entire family as well as other professionals. Parents of an autistic child or adult must continually educate themselves about new treatments and keep an open mind. Some treatments may be appropriate for some individuals but not for others. Many treatments have yet to be scientifically proven. Treatment decisions should always be made individually after a thorough assessment and based on what is suitable for that child and his or her family.

It is important to remember, despite some recent denials, that autism is virtually a lifelong condition. Treatment will change as the individual develops. Families must beware of treatment programs that give false hope of a cure. Acceptance of the condition in a family member is a very critical, foundational component of any treatment program and is understandably quite difficult.

Several medications have been tried or are under current scrutiny for the treatment of autism. No medication has consistently proven to be of benefit in closely controlled clinical trials. In the past, a piece on a television news show prompted a great deal of interest in the hormone secretin as a treatment for autism. An autistic child with chronic gastrointestinal complaints showed dramatic improvement following some routine testing performed by a gastroenterologist during which a small dose of secretin was administered. The family and their physicians felt that the secretin may have resulted in the improvement in the symptoms of autism. Many physicians began prescribing secretin, which can be costly for their autistic patients. However, studies published appear to completely refute the claim that secretin treatment benefits autistic patients. This example underscores the importance of good clinical trials in determining whether a drug will help patients with autism.

Autism At A Glance

• Autism is characterized by impaired development in social interaction, communication, and behavior.
• The degree of autism varies from mild to severe.
• Severely afflicted patients can appear to have a profound intellectual disability.
• The cause of autism is unknown.
• The optimal treatment of autism involves an educational or vocational program that is suited to the developmental level of the child or adult, respectively.

For More Information

The Autism Society of America
7910 Woodmont Ave. Suite 650
Bethesda, MD 20814
301-657-0881 or
1-800-3AUTISM fax: 301-657-0869
URL: http://www.autism-society.org/
National Society For Children and Adults With Autism
1234 Massachusetts Avenue N.W., Suite 1017
Washington, DC 20005
(202) 783-0125

Center for the Study of Autism
FEAT Families for Early Autism Treatment
National Institute of Neurological Disorders and Stroke