According to the "American Psychiatric Association Diagnostic Manual", (DSM-III), Pervasive Developmental Disorder (PDD) has two subtypes. The first is Autistic Disorder, which is the more classic and severe form. The second type, Pervasive Developmental Disorder Not Otherwise Specified (PDDNOS), is the more general type which is diagnosed when there is a basic impairment in relation and communication.
The majority of the children seen at the Spectrum Center are under the age of five, with many of these under the age of three. A typical history is a failure to develop, or a regression in the development of language. The majority of families report normal development during the first year. In retrospect they may recall certain sensitivities to touch, movement, light, and sound, which became more severe later. They may also recall some delay in gestural communication, such as "waving bye-bye", or playing peek-a-boo, however these symptoms were not sufficient to cause alarm for most families. Some parents feel, however that they always had an uneasy feeling, yet were reassured by doctor's and other family members. In some history's there are reports of severe colic, severe sensitivities, and poor eye contact since infancy.
When symptom are absent or minimal in the first year, family's report significant changes in behavior during the second year. Language that was developing, suddenly or gradually stop. Parents report they will hear a word, never to hear it again. Words and phrases that were well established fade away. There is often a change in eye contact and level of engagement. Play becomes aimless or repetitive in nature. Often sensory sensitivities emerge or become more severe. Behavior often becomes more rigid or inflexible. The children may become very upset if there is a change in routine. Temper tantrums often become more frequent and severe in nature as the child has no language to communicate their needs. There is often a change in eating habits as the children become increasingly picky and limited in what they will eat.
Another significant history is of frequent ear infections and anti-biotic use. Although this is observed in a majority of the children, there are children who present with the above disorder without any history of ear infections or anti-biotic use.