The Effects of Verbal Mediating Behavior on Derived Stimulus Equivalence Relations

The present study used a reversal design with six participants divided into two groups CABA and BACB, to test the effects of a rhyming distractor on the accuracy of responses according to derived relations. The DMTS preparation was used for tests for derived relations and a talk aloud procedure was used to measure the verbal behavior emitted by participants during the 6-s delay for the A and B conditions. The results indicated during the B condition (s) the distractor suppressed accurate responses with directly trained, symmetry, and equivalence relations and during the A and C conditions, when the distractor was absent, five out the six participants met mastery criteria for the directly trained and derived relations. Furthermore, the verbal behavior of all the participants observed during the distractor absent conditions indicated they generated responses regarding the relations between the stimuli or emitted self-echoics of tacts they produced, and this behavior was suppressed and accurate responses were reduced during the B conditions. The results also indicated longer latencies in the B conditions between the comparison and the selection than in the A or C conditions when the distractor was absent. The role of verbal behavior as mediating derived relations is discussed. The limitations of the study included a low number of participants, the inference of the effects of verbal behavior on accurate responding, and role of perceptual behavior as mediating behavior which was not investigated. Future research should examine the role of verbal behavior in different phases of the DMTS preparation such as the presentation of the comparison and the selection. Future research should also examine the role of perceptual behavior in tests of derived relations using DMTS