Pervasive Developmental Disorders

Pervasive (per-VAY-siv) developmental disorders are a group of conditions in which the brain fails to develop normally, resulting in serious problems with communication, social interaction, and behavioral development.


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Asperger disorder

Rett disorder


Childhood disintegrattve disorder

What are Pervasive Developmental Disorders?

Pervasive developmental disorders are conditions that prevent children from developing normal communication and normal social abilities. Signs of these conditions begin to appear in the very early years of childhood. Some forms of pervasive developmental disorder (PDD) are milder and other forms are more severe. Most children with these conditions have very limited interests and activities, and some engage in unusual behavior, such as rocking, flapping their hands, or even behavior that causes self-injury.

PDDs include autism (AW-tizm), Asperger (AS-per-ger) disorder, Rett disorder, and childhood disintegrative disorder. The term "pervasive developmental disorder" refers to the whole group of conditions, but it sometimes is used to refer to milder forms of autism. The word "pervasive" means affecting all aspects of something. It is used for these conditions because they can affect all aspects of a person's life.

What Are the Types of Pervasive Developmental Disorders?

Autism is a brain disorder that affects children within the first 3 years of life. Sometimes these children may appear to develop normally for a time in early infancy. The word "autism" comes from the Greek word meaning "self." It was chosen for the disorder because of the characteristic self-absorption of people who have it. Indeed, children with autism appear to live in a world of their own, often seeming not even to notice members of their own family around them. They seldom make eye contact with other people or share their interests.

Children with autism are socially isolated. Their social problems are made worse by the fact that their language skills usually do not develop normally. Some children may never learn to talk. Others may talk, but they use language inappropriately, perhaps simply repeating the words of others or reversing the meanings of "I" and "you." They may repeat certain behavior, such as hand-flapping or body-rocking, over and over for no apparent purpose.

Asperger disorder is generally thought to be a milder form of pervasive developmental disorder, and it shares with autism the features of social isolation and lack of responsiveness to other people. The difference between Asperger disorder and what is called "classic" autism is that a child with Asperger disorder has the intellectual function and language skills of a normal child of the same age. In fact, children with this disorder often have excellent vocabularies, but do not use their language skills for appropriate conversation. Socially, they often lack good give-and-take interactions. They may memorize and then recite timetables or lists (for example, facts from almanacs) or have intense and very focused interests (for example, mechanical devices). A child with Asperger disorder may know the names and numbers of every Amtrak engine or be an expert on their town's fire stations. Also, their social interactions often revolve around their overly focused interests ("Which fire station is near your house?" may be a way to say "Hello").

Rett disorder is a severe genetic * developmental condition that affects only girls. At first, the child develops normally, usually for about 1 to 2 years after birth. She may even begin to walk and talk. Then she starts to lose these skills and may show signs of a stiff-legged walk. Losing the ability to use words to communicate, she also may lose interest in making friends. A typical physical sign of Rett disorder is that the child's head stops growing at the normal rate.

* genetic je-NE-tik) pertains to the genes, which are contained in the chromosomes found in the cells of the body. Genes help determine a person's characteristics, such as hair or eye color, and they also are involved in the cause of some medical conditions. They are inherited from a person's parents.

Childhood disintegrative disorder has signs that are in many ways similar to those of autism. An important difference is that in childhood disintegrative disorder a child may develop normally for 2 to 10 years. Then the child may begin to lose some combination of social or communicative skills, bowel or bladder control, or motor skills (physical coordination).

What Causes Pervasive Developmental Disorders?

Rett disorder is now understood to be caused primarily by a faulty gene. The causes of most cases of autism, Asperger disorder, and childhood disintegrative disorder are not yet known. Because autism and Asperger disorder tend to run in families, it is believed that they are at least partly caused by faulty genes. Some authorities believe that childhood disintegrative disorder may be the result of damage to the developing brain, but it is not known how this damage occurs.

How Are Pervasive Developmental Disorders
Diagnosed and Treated?

In order to diagnose a developmental disorder, a doctor or psychologist first asks the child's parents questions about the child's early development and then carefully observes the child to identify possible signs of impairment in social activities, behavior, and communication.

There are no cures for pervasive developmental disorders, but many children do improve over time. Early intervention is key to developing social and language skills. Therefore, prompt and proper diagnosis is important, so that well-planned special training and education can begin. Children are taught how to overcome the effects of certain impairments and to build on the skills they have. Medication may be used to treat special problems, such as seizures * or hyperactivity * . One key to treatment is the development of a communication system that can help children with their social skills. One communication system that has proven to be effective uses "picture exchanges." For example, if a child wants a drink, he hands the teacher a picture (symbol) of a drink. Pictures are gradually added together (picture of orange + picture of drink) and paired with words. Often, words then begin to replace the picture exchange system.

Often, children with these disorders can learn to attend to their basic needs such as self-feeding, dressing, and personal care. Many individuals with milder developmental problems learn to use language effectively and learn to relate well enough to gain some degree of independence (have a job; live in a group home) as adults. Some people with autism and Asperger disorder make rapid developmental progress in school and eventually may live by themselves.

Many individuals with PDDs, however, never lean to relate socially, develop a communication system to express their needs, or rid themselves of unusual behaviors such as rocking or hand-flapping.

* seizures (SEE-zhurs) are sudden attacks of involuntary (uncontrollable) body movements, changes in behavior, or loss of consciousness that result from bursts of abnormal electrical energy within the brain.

* hyperactivity (hy-per-ak-TI-vi-tee) is overly active behavior, which makes it hard for a person to sit still.



Attwood, Tony. Asperger's Syndrome: A Guide for Parents and Professionals . Philadelphia: Jessica Kingsley Publishers, 1997.

Lewis, Jackie, and Debbie Wilson. Pathways to Learning in Rett Syndrome. London: David Fulton, 1998. Written for parents.

Seroussi, Karyn. Unraveling the Mystery of Autism and Pervasive Developmental Disorder: A Mothers Story of Research and Recovery. New York: Simon and Schuster, 2000. Written for parents.

Organization , A. I. duPont Hospital for Children, 1600 Rockland Road, Wilmington, DE 19803. This organization is dedicated to issues of children's health. Their website has much valuable information for children, teens, and parents. For specific information on autism, go to .

See also
Asperger Disorder
Rett Disorder

Also read article about Pervasive Developmental Disorders from Wikipedia

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