Acquisition of simple motor imitative behavior in mentally retarded and nonretarded children.

The effects of social reinforcement and population on two simple motor tasks which were embedded within a contingently reinforced imitation task were explored. A Social Reinforcement Type x Population interaction was observed, where the nonretarded children performed at higher levels under informative social reinforcement (right-correct) and at lower levels under affective social reinforcement (good-fine); the opposite was observed for the retarded children. In addition, one motor response was imitated to a higher degree than the other response.