| PDD | <neurology, psychiatry> A large group of developmental disabilities which are neurological disorders, usually of unknown cause. Characteristics include reduced abilities to understand language and communicate normally, reduced ability to socially interact with others in a normal manner, and limited variety in activities and interests. Individuals will also often respond in unusual ways to sensations, engage in repetitive activities, and resist changes to the environment or to daily routines. Types of pervasive development disorder include autism, Retts Syndrome, Hellers Syndrome, and Aspergers Syndrome. Acronym: PDD (12 Jan 1998) |
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