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What is "Autism" or "Pervasive Development Disorder?"
The term "autism" was first coined in 1943 by Dr. Leo Kanner. Dictionaries often define autism as the tendency to daydream, to fantasize, to view life in terms of ones own needs or desires regardless of reality. However, through medical research, the condition known as autism has been considerably broadened to include many childhood developmental disorders. Today physicians usually apply the term of pervasive developmental disorder to identify what is commonly called autism.
Core symptoms which define autism consist of deficits of varying degrees in three areas of development:
1. Defective social or personal relatedness behaviors
2. Language or, more broadly, communication difficulties
3. Play or preferred activities which are characterized by preoccupations having a repetitive or stereotyped quality.
The severity of autism varies widely. Experts agree that the cause of autism has neurobiological origins, and is not the result of poor parenting. Dysfunction of specific nerve networks appears to be responsible for autism. This dysfunction may be secondary to a variety of disorders that affect the brain. Unfortunately, the precise cause of autism in the majority of children is not yet well understood.
Many individuals with more severe autism have identifiable underlying medical conditions. These may include a variety of congenital, chromosomal, metabolic, and occasionally acquired conditions. For this reason, careful medical and neurological evaluation is essential.
How common is the condition?
Recent studies have shown that autistic disorders are not rare and occur in approximately one in a thousand children, or about 0.1 percent of the nations total population of children. It may affect even more children since autism varies considerably in severity and might not be easily recognized in milder cases.
How do we identify autism in infants and in young children?
Autistic children do not socially interact very well with other people and do not communicate well. They often are very restricted in their activities and interests. A young autistic child may not make eye contact with others. As young infants, they do not seem to enjoy the normal cuddling most babies do.
When somewhat older, they may fail to develop the ability to speak at a normal rate. They do not play with toys in a usual fashion, but rather have an intense interest in twirling or spinning objects, and play in this fashion for hours at a time. In addition, they are extremely fearful when facing new situations and people, always preferring to see familiar faces. They may develop unusual, stereotyped body movements such as hand flicking, twisting, head banging or complex whole body movements.
Lesser affected youngsters may have notable abnormalities of speech. They may intone words or phrases in rhymes, verses, or accents, and they may sing melodies with unusual inflections of speech. Also, they may exhibit excessive "echolalia," or uncontrolled and immediate repetition of words or phrases spoken by another person. They may tend to prattle about meaningless conversation, such as repeating words verbatim from a television or radio advertisement.
Are there forms of mild autism or pervasive developmental disorder?
Children with mild autism or pervasive developmental disorder may have behaviors which are not so conspicuous. These children may, in fact, have normal or above-average intellectual ability. Their manifestations of autistic behavior may include a lack of any ability to make friendships with other children, although they can relate to family members and to adults. They sometimes seem to misunderstand or to have difficulty picking up how to speak or respond to others, they may misinterpret a social gesture, or they may have difficulty in enjoying a joke. Although their speech may be adequate, it may be hard for them to initiate or carry on a conversation even though they may indulge in a lengthy discourse on a single subject, regardless of the response or interest of others. See also Asperger's Syndrome below.
Individuals with mild autism, moreover, often have very restricted interests. When with other people they may recite facts about obscure subjects which have little or no relevance to the overall conversation. Or, if an attempt is made to draw them into the conversation, they may ignore others in the room and align objects or toys on a table or on the floor.
What is the relationship between autism or pervasive development disorder and IQ?
The majority of autistic youngsters have IQs less than 70, or are considered to be mentally retarded. Individuals who are considered to be severely mentally retarded often exhibit many of the behavioral features of autism, such as self-stimulated hand movements, head banging or complex body movements. In autistic children, early IQ scores are often inaccurate.
Approximately one-third of youngsters with autistic behavior are not in the mentally retarded range, and may be of normal or above-average intellectual ability. It is among this group of non-retarded children that autism probably is most underdiagnosed. These youngsters would benefit greatly from small, structured classroom situations where they can learn the rules of social interaction. The rules of social conduct do not come naturally, so these youngsters must develop their skills in learning social conduct in much the same way as individuals learn a foreign language. Children who have normal or above-average intelligence, but who exhibit autistic features, generally have a much better chance of being "normal" adults, particularly if they are given support in childhood.
How is perception affected?There is a strong suggestion that individuals with autism, or pervasive childhood disorder, may have an impaired perception of the world, preventing them from seeing things from another persons point of view. A high functioning child with autism may understand what other people are thinking, but lack the ability to infer or truly understand what a person means by his emotional expression and behavior. This accounts for his difficulty in understanding the subtleties of human social communication, including body language and humor. This lack of understanding cannot be explained by suspecting a hearing deficit.
Other things you should know about autism:
Childhood schizophreniashares some features of autism but is chiefly characterized by auditory hallucinations, delusions and incoherences.
Medical researchers have recently defined biological syndromes that often are associated with autism. The first is referred to as the Fragile X syndrome, and is a chromosomal anomaly, perhaps the most commonly inherited form of retardation often associated with autistic features. This chromosome occurs chiefly in boys. The second is a disorder known as Retts syndrome, which occurs almost exclusively in girls. Retts syndrome is characterized by a slow deterioration of motor skills and convulsions, and is associated with autistic features. It is believed that Retts syndrome involves abnormalities in a number of important chemical messengers, or neurotransmitters.
Early intervention in diagnosing and treating youngsters suspected of being autistic can be most helpful in improving the overall prognosis. Speech and language therapy is considered extremely important. Intensive behavioral modification therapy is recognized as an essential part of a therapeutic program.
See Dr. Isabelle Rapin's article on Autism
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