Comparison of match-to-sample and respondent training of the blocking effect in equivalence classes

Abstract

Blocking occurs when previous conditioning with one stimulus reduces, or blocks, conditioning to a second stimulus when the stimuli are later presented as a compound. Basic research has suggested blocking may occur during equivalence class formation. Although both match-to-sample and respondent-type training are procedures used to facilitate emergent relations, research on blocking within equivalence classes has only been conducted using match-to-sample procedures. Since the two procedures are based on different types of conditioning, information on the presence of blocking in respondent-type equivalence classes would contribute to a more coherent explanation of equivalence class formation. Thus, the purpose of the present study was to compare match-to-sample and respondent-type training for their susceptibility to blocking in three-member equivalence classes. Results for the four participants who formed equivalence classes in the match-to-sample condition were mixed, with some displaying evidence of blocking and others displaying the formation of four-member equivalence classes. The two participants who formed equivalence classes in respondent-type training both showed the inclusion of the stimulus used in the blocking preparation and subsequent formation of four-member equivalence classes. Results are discussed with regard to implications for applied practitioners and directions for future research.