Four of eight low-functioning, developmentally delayed preschool children initially failed to demonstrate expected oddity responding. In the context of a multiple baseline across-subject design, each of the previously unsuccessful children demonstrated significant increases in the percentage of correct oddity responses immediately upon…

The study examined the effectiveness of enhancing perceptual differentiation in the training of four developmentally delayed preschool children who were so low-functioning that they did not demonstrate oddity responding (ability to choose one distinct stimulus from a group of identical stimuli). Instead of the Arabic numerals used in the original…

This study examined the matching and sequencing of quantities, numerals, and arbitrary forms by two individuals with mental retardation. Results showed that sequence training did not readily lead to new matching performances, unlike prior research with college students. Instead, training in matching to sample yielded emergent sequence production…