Verbal Mediation During Auditory Equivalence Class Formation Using Go/No-Go Successive Matching-to-Sample

Successive matching-to-sample (S-MTS) with a go/no-go response requirement has previously produced equivalence classes with nonverbal auditory stimuli among college students. When participants are required to talk aloud during posttests (protocol analysis), their verbal behavior tends to match their selection performance. However, in some cases, the protocol analysis seems to interfere with posttests, in that equivalence yields are lower when participants are required to talk aloud. Thus, the current study replicated and extended previous research by requiring participants to complete emergence posttests before introducing training for the protocol analysis. Subsequently, participants completed one additional block of the transitivity/equivalence posttest with the talk-aloud requirement. Additionally, participants completed tact and intraverbal tests following emergence posttests to further assess possible verbal-mediation strategies. The results showed that six of eight college students formed equivalence classes, suggesting that previous failures could have been influenced by the talk-aloud requirement. Further, there was a positive correlation between verbal and nonverbal (selection) responses suggesting the possibility that verbal mediation may have contributed to equivalence-class formation.