Acquisition of conversational response skills by young Down syndrome and nonretarded young children.

The acquisition of conversational response skills by young retarded and nonretarded children matched for chronological age (CA) and expressive linguistic ability was compared. Retarded children showed delayed response performance in comparison with CA-matched nonretarded peers. When matched for language level, however, retarded children demonstrated significantly greater response abilities than did nonretarded children. These findings indicate that the language development process of retarded children is developmentally delayed and different with respect to the synchrony of syntactic development and communicative competence. The findings further suggest that the acquisition of conversational response rules is not determined by the child's expressive language ability as measured by a mean length of utterance score, but is directly influenced by social-experiential factors as measured by the child's age.