Sign Language Acquisition: Language Development in Children of Deaf Parents and Implications for Other Populations.

Abstract

An 18-month longitudinal investigation of sign language acquisition in children of deaf parents is reported, and the implications of sign language research find ings for nonspeaking populations and developmental theory are discussed. In the study, the language, cognitive, and motor developments of 13 very young children were assessed in home visits that occurred about every 6 weeks. The subjects' acquisition of a sign language vocabulary was clearly accelerated in comparison with the norms for spoken language development. The subjects ac quired their first recognizable sign at an average age of 8.6 months, and achieved a 10-sign vocabulary at a mean age of 13.2 months. At the time the subjects began to produce signs, they were typically only partly through Stage IV, the sensorimotor period, as assessed by the Uzgiris-Hunt scales. These re sults indicate that some revision of views on cognitive prerequisites for language is necessary. Finally, the implications of the present study are discussed, and there is a brief review of sign language training programs for various language disordered populations.