Reversal and partial reversal shifts with verbal material

Abstract

A series of four studies was conducted to investigate the influence of mediating representational responses on reversal and partial-reversal shifts involving verbal material. The general assumption tested was that the speed with which a reversal shift is executed depends on the accessibility of appropriate mediating representational responses. In Exp. I Ss were required initially to sort eight items into two categories and then during post-shift training to either switch the sorting response for every item (reversal shift) or for only half of the items in each category (half-reversal shift). Two kinds of verbal items were used: eight words, each one of which was an instance of one of two concepts, and eight unrelated consonant trigrams. With the conceptual words the reversal shift was executed more rapidly but no difference between a reversal and half-reversal was found with the trigrams. It was also discovered that up to 24 post-criterion trials of overlearning had no effect on post-shift behavior with either kind of verbal material. Experiment II found that overlearning up to 40 post-criterion trials had only minimal effects on reversal shifts involving trigrams. In Exp. III four kinds of shifts (one-quarter, one-half, three-quarters, and full-reversal) were compared with both conceptual words and trigrams. The full-reversal with conceptual instances proved to be the easiest. No significant difference existed among the other seven groups. Experiment IV, in which Ss initially sorted the conceptual instances into mixed categories and then shifted into either conceptually consistent categories or a reversal shift, showed the latter to be more difficult, suggesting that the accessibility of the representational response was more important to post-shift behavior than the reversal shift per se. The relevance of these results to mediational S-R theory and the verbal-loop hypothesis was discussed.