The Long-Term Retention Of Generalized Equivalence Classes

Abstract

This experiment examined the retention of generalized equivalence classes. Seventeen subjects completed matching-to-sample training, in which two-element stimulus compounds were presented as sample stimuli, and an equivalence test, in which those compounds were separated and each element was tested separately for its entry into equivalence relations with the other stimuli. A generalization test was then conducted, in which dimensional variants (along the dimension of hue) of one member of each class were presented as sample stimuli on test trials for two generalized symmetry relations and one generalized equivalence relation. Equivalence and generalization retention tests were conducted for 8 subjects 2–3 months following their initial laboratory session. This experiment also employed a verbal protocol analysis, in which subjects’ overt verbal behavior was recorded during both experimental sessions and examined in light of subjects’ performances. More subjects demonstrated the retention of symmetry relations than within-compound or equivalence relations, and all subjects who showed the maintenance of equivalence and within-compound relations also showed the maintenance of symmetry relations. Generalized classes were shown to have remained stable over time for some subjects, while other subjects demonstrated the emergence of subject-defined generalized classes during the generalization retention test. Verbal protocol analyses showed that all subjects emitted a relatively greater frequency of verbal descriptions of stimulus relations under extinction testing situations than during training, and class-consistent names for generalized class-members appeared to be likely, but not necessary for the generalization of class membership.