An evaluation of a visual-visual successive matching-to-sample procedure to establish equivalence classes in adults.

Traditionally, behavior analysts have studied stimulus equivalence using a matching-to-sample (MTS) preparation. Although researchers have shown the utility of MTS to yield equivalence classes, the procedure requires several prerequisite skills for a learner to accurately respond. Previous research with humans and nonhumans has shown that relational responding can be produced via compound stimulus discrimination and successive matching-to-sample (S-MTS). We conducted four experiments with college students to further evaluate the effectiveness of S-MTS in the establishment of stimulus relations. S-MTS trials consisted of the presentation of a single sample stimulus followed by one comparison in a fixed location on a computer screen. Depending upon the sample-comparison relation, participants touched (i.e., go) or did not touch (i.e., no-go) the comparison stimulus. Following training of the baseline relations (AB/BC), we assessed the emergence of symmetry, transitivity, and equivalence performances (i.e., BA/CB and AC/CA). Results support the utility of the S-MTS procedure as a possible alternative to traditional MTS. This study has direct implications for participants for whom traditional three-array MTS procedures may be challenging.