Communication, cognition, and social interaction in the Angelman syndrome.

Persons with Angelman syndrome (AS) have mental retardation, epilepsy, and a characteristic "puppet-like" gait. Behaviorally, they are distinctive because they have no speech and have excessive laughter. A speech and communication evaluation of 7 persons with AS was performed to provide improved understanding of the speech deficit. Assessments included prelanguage and language development, oral motor abilities, and cognitive and social interaction skills. Results indicate that the typical lack of speech may not be due to mental retardation alone. Oral motor dyspraxia, and deficits in social interaction and attention were characteristic of AS and contributed to the lack of speech.