Mentally retarded adolescents' breadth of attention and short-term memory processes during matching-to-sample discriminations.

Twenty-two moderately and severely mentally retarded adolescents and 22 nonretarded children participated in an experiment designed to examine processes contributing to matching-to-sample deficits of low mental age (MA) retarded persons. One-half of the subjects rehearsed color, form, and size cues during delay intervals. Nonretarded subjects performed better than did retarded subjects on immediate and delayed retention tests. There was no difference in rate of forgetting, and rehearsal improved delayed test performance equally for both groups. Although immediate test results indicated that low-MA persons are capable of multiple-looking, these results also suggest that retarded persons attend to fewer dimensions than do nonretarded children.