What are pervasive developmental disorders (PDD)?
Pervasive developmental disorders, also called autism spectrum disorders, most often can be identified in the early years of a child's life. Children with PDD have difficulty in areas of development or use of functional skills such as language, communication, socialization, and motor behaviors. Examples of PDD include the following:
Autism (autistic disorder)
Asperger's disorder
Rett's disorder
Childhood disintegrative disorder (also called disintegrative psychosis)
What causes pervasive developmental disorders?
The specific causes of pervasive developmental disorders are not known. Children with PDD have problems processing information, thus the causes of PDD have something to do with differences in brain function. However, parenting behaviors are not the cause, or even a contributing factor, to the cause or causes of PDD.
Who is affected by pervasive developmental disorders?
Information from the National Institute of Mental Health and the Centers for Disease Control and Prevention (CDC) estimates that an average of one in 110 children has some form of PDD. PDD is found four to five times more frequently in boys, with the exception of Rett's disorder, which is found only in girls.
What are the symptoms of pervasive developmental disorders?
The following are the most common symptoms of some pervasive developmental disorders. However, each child may experience symptoms differently.
The symptoms of autism may include:
Does not socially interact well with others, including parents
Shows a lack of interest in, or rejection of, physical contact. Parents describe autistic infants as "unaffectionate." Autistic infants and children are not comforted by physical contact.
Avoids making eye contact with others, including parents
Fails to develop friends or interact with other children
Does not communicate well with others
Is delayed or does not develop language
Once language is developed, does not use language to communicate with others
Has echolalia (repeats words or phrases repeatedly, like an echo)
Demonstrates repetitive behaviors
Has repetitive motor movements (such as rocking and hand or finger flapping)
Is preoccupied, usually with lights, moving objects, or parts of objects
Does not like noise
Has rituals
Requires routines
The symptoms of Asperger's disorder may include:
Normal development of speech, self-help skills, thinking skills (cognitive development), and curiosity about their environment
Difficulty with social interactions such as making friends, sharing ideas, sharing pleasures or accomplishments, facial expressions (smiles), or eye contact with others
Repetitive and stereotyped patterns of behavior or play such as strange routines or rituals (hand or finger flapping, collecting strange objects such as lint)
Capable of originality and creativity focused on isolated areas of interest
The symptoms of Rett's disorder may include:
Normal pregnancy, birth, and newborn growth and development
Normal growth and development during the first 5 to 18 months of life
Normal head circumference at birth
Following a period of normal development of at least five months, all of the following changes occur:
Size of the child's head does not grow as much as it should between the ages of 5 and 48 months
Loss of previously learned useful hand skills (such as reaching for and grasping an object) and the development of stereotyped hand movements that are not useful to the child, such as hand wringing
Loss of socially engaging behaviors, such as smiles and eye contact (however, these behaviors may be re-developed later)
Loss of coordinated walking or body movements
Expressive (ability to verbally express thoughts) and receptive (the ability to understand and use language that is heard or seen) language skills become impaired and severe psychomotor retardation develops
The symptoms of childhood disintegrative disorder may include:
At least two years, and usually up to four years, of normal development including speech, social interactions and relationships, and play and adaptive behavior
Over a short period of time (a few months), severe loss of functioning in social, communication, and behavioral skills occurs. Without any obvious illness or cause, children experiencing disintegrative disorder become anxious, irritable, negative, and disobedient with frequent temper tantrums and outbursts for no apparent reason. These children have a complete loss of speech and language, understanding of language, and a decrease in thinking (cognitive) skills.


