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Pervasive developmental disorder

Pervasive developmental disorder (PDD) is a disorder characterized by social interaction and communication difficulties in addition to repetitive behavior, which hinders the normal development of the child. There are five forms of this disorder, of which autism is the most common. PDD appears during the first years of life for reasons that are not yet clearly known (genetic anomaly, complication during pregnancy, metabolism or cerebral activity problems, environmental factors, etc.). PDD may be associated with neurological problems like epilepsy, blindness, or deafness, as well as psychiatric problems: mental retardation, self-mutilation, depression, and obsessive compulsive disorders. There is no cure, but there are pedagogical methods that allow children suffering from PDD to develop independence.

Forms of PDD

The five forms of PDD are autism, nonspecified pervasive developmental disorder, Asperger’s syndrome, Rett syndrome and childhood disintegrative disorder. Childhood disintegrative disorder and Rett syndrome, more severe and more rare, manifest themselves particularly through a serious intellectual deficiency, as well as a significant language and psychomotor handicap. Nonspecified pervasive developmental disorder and Asperger’s syndrome, not as severe, are characterized by social interaction difficulties, without language or intellectual development handicaps, and by restricted activities and interests that are sometimes associated with exceptional performance (music, math, etc.). Autism has a large number of symptoms that present themselves in varying degrees from one person to another.


Autism affects 10 to 15 people out of 10,000 in the world and 3 to 4 times more boys than girls. It is characterized by an alteration in verbal and nonverbal communication, reduced or atypical social interaction, stereotypical behavior, and restricted interests. Autism appears before the age of 3 and manifests itself in aversion of the eyes, through unadapted contextual reactions, social isolation, language handicap, tireless repetition of heard words, repetitive use of objects, swaying of the body and hands, etc. Some autistic people possess higher than average abilities in particular domains while lacking in others. Autism is sometimes accompanied by insomnia, anxiety, eating disorders, and motor skill problems. The development of an autistic child depends on the prematurity of the diagnosis, the degree of the affliction, and the psychopedagogical methods implemented.

pervasive developmental disorder

Autistic children may avert their eyes or focus them beyond the speaker.

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