Two studies investigated the transfer of respondent elicitation through equivalence classes. In Experiment 1, match-to-sample procedures were used to teach 8 subjects two four-member equivalence classes. One member of one class was then paired with electric shock, and one member of the other class was presented without shock. All remaining stimuli were then presented. Using skin conductance as the measure of conditioning, transfer of conditioning was demonstrated in 6 of the 8 subjects. In Experiment 2, similar procedures were used to replicate the results of Experiment 1 and investigate the transfer of extinction. Following equivalence training and conditioning to all members of one class, one member was then presented in extinction. When the remaining stimuli from this class were then presented, they failed to elicit skin conductance. In the final phase of the experiment, the stimulus that was previously presented in extinction was reconditioned. Test trials with other members of the class revealed that they regained elicitation function. These results demonstrate that both respondent elicitation and extinction can transfer through stimulus classes. The clinical and applied significance of the results is discussed.Key words: stimulus equivalence, transfer of function, classical conditioning, extinction, skin conductance, fear, humans Stimulus equivalence has attracted a good deal of interest recently among behavior-analytic researchers. Much of the interest stems from the contention that stimulus equivalence may provide the basis for a behavior-analytic account of symbolic behavior, language, and apparently novel behavior (e.g

Schedule sensitivity has usually been examined either through a multiple schedule or through changes in schedules after steady-state responding has been established. This study compared the effects of these two procedures when various instructions were given. Fifty-five college students responded in two 32-min sessions under a multiple fixed-ratio 18/differential-reinforcement-of-low-rate 6-s schedule, followed by one session of extinction. Some subjects received no instructions regarding the appropriate rates of responding, whereas others received instructions to respond slowly, rapidly, or both. Relative to the schedule in operation, the instructions were minimal, partially inaccurate, or accurate. When there was little schedule sensitivity in the multiple schedule, there was little in extinction. When apparently schedule-sensitive responding occurred in the multiple schedule, however, sensitivity in extinction occurred only if differential responding in the multiple schedule could not be due to rules supplied by the experimenter. This evidence shows that rule-governed behavior that occurs in the form of schedule-sensitive behavior may not in fact become schedule-sensitive even though it makes contact with the scheduled reinforcers.

In two equivalence experiments, a "think aloud" procedure modeled after Ericsson and Simon's (1980) protocol analysis was implemented to examine subjects' covert verbal responses during matching to sample. The purpose was to identify variables that might explain individual differences in equivalence class formation. The results from Experiment 1 suggested that subjects who formed equivalence classes described the relations among stimuli, whereas those not showing equivalence described sample and comparison stimuli as unitary compounds. Because Experiment 1 only demonstrated a correlation between describing stimulus compounds and the absence of equivalence classes, a second study was conducted. In Experiment 2, equivalence class formation was brought under experimental control through pretraining manipulations that facilitated responding either to stimulus compounds or to relations among stimuli. The results demonstrated that a history of describing stimulus compounds, when compared with describing the relations among the stimuli, interfered with the emergence of stimulus equivalence. These findings clarify individual differences in stimulus equivalence. They also demonstrate the utility of analyzing verbal reports to identify possible variables that can be manipulated experimentally.

The transformation of functions refers to the untrained acquisition of stimulus functions among members of stimulus equivalence classes or relational frames. Although it is widely assumed that contextual control over the transformation of fuctions must exist, this has not yet been conclusively demonstrated in laboratory studies. Four experiments are reported in which (a) stimulus equivalence classes were established, (b) a conditional stimulus function was trained for one member of each of the classes, and (c) multiple-exemplar procedures were used to train and test for contextual control over the transformation of the stimulus function within the classes and to assess whether it generalized to new equivalence classes. Although a significant amount of training was required, the procedures ultimately resulted in the contextual control of function transformation for 9 of 10 participants and generalized contextual control for 4 of 5 participants.

Adults were selected on the basis of their scores on the Scale for Personality Rigidity (Rehfisch, 1958a). Their scores served as a measure of hypothesized rule governance in the natural environment. Experiment 1 studied the effects of accurate versus minimal instructions and high versus low rigidity on performance on a multiple differential-reinforcement-of-low-rate (DRL) 4-s fixed-ratio (FR) 18 schedule. When the schedule was switched to extinction, accurate instructions and high rigidity were associated with greater perseveration in the response pattern subjects developed during the reinforcement phase. In Experiment 2, the effects of rigidity and of accurate versus inaccurate instructions were studied. Initially, all subjects received accurate instructions about an FR schedule. The schedule was then switched to DRL, but only half of the subjects received instructions about the DRL contingency, and the other half received FR instructions as before. Accurate instructions minimized individual differences because both high and low scorers on the rigidity scale earned points in DRL. However, when inaccurate instructions were provided, all high-rigidity subjects followed them although they did not earn points on the schedule, whereas most low-rigidity subjects abandoned them and responded appropriately to DRL. The experiments demonstrate a correlation between performances observed in the human operant laboratory and a paper-and-pencil test of rigidity that purportedly reflects important response styles that differentiate individuals in the natural environment. Implications for applied research and intervention are discussed.DESCRIPTORS: rule-governed behavior, instructional control, individual differences, insensitivity to contingencies, multiple schedules A number of researchers have shown that, in the human operant laboratory, verbal rules compete with programmed contingencies of reinforcement and often produce an apparent insensitivity to these contingencies (e.g