Inducing select/reject control in a matching-to-sample procedure with observing response: Effects on stimulus equivalence.

This study investigated a three-choice matching-to-sample procedure with an observing-response requirement to induce select and reject control during baseline training and examined their effects on the formation of equivalence classes. The study involved four girls, aged 8 to 10 years, who participated in a computer-based task that alternated between conditions designed to induce select and reject control by requiring observing responses to display the stimuli. In the select-control condition, the correct stimulus was revealed first on at least 75% of the trials, increasing the likelihood of selecting the correct stimulus without seeing the incorrect ones. In contrast, in the reject-control condition, the correct stimulus was revealed third on at least 75% of the trials, forcing the display of both incorrect stimuli. This procedure successfully generated both select and reject control, which increased progressively with the accuracy during baseline training trials. Select control was more prominent than reject control, but both led to the formation of equivalence classes. This finding suggests that reject control does not hinder control by the correct stimulus.