Association for Behavior Analysis International

Stimulus equivalence is a special case of generalization in which stimuli acquire novel functions due to histories of reinforcement which have indirectly related them to other, topographically distinct, stimuli. Although work on this topic has typically focused on transfers of operant functions (e.g., conditional discriminations), some research demonstrated that Pavlovian (stimulus-stimulus) functions can also be transferred to novel stimuli through the same process (e.g., skin conductance can be elicited by stimuli which participate in frames of equivalence with shock). However, little is known about the parameters across which the transfer of Pavlovian functions is possible. For example, Behavioral-Momentum Theory (BMT) explains that context-specific operant response persistence is the product of a Pavlovian conditioning process involving reinforcement but it is unclear whether this effect can be transferred to novel stimuli via stimulus equivalence. Three college students completed a three-part experiment to explore this possibility. All demonstrated equivalence during Experiment 1. One of three demonstrated patterns of persistence consistent with BMT during Experiment 2. Persistence did not transfer to novel stimuli during extinction in Experiment 3 (IOA and fidelity scores fell above acceptable ranges for all experiments). These results suggest equivalence may not always facilitate the transfer of all stimulus functions.

Effort discounting refers to the decrease in subjective value of a reward as a function of effort for the reward. In previous experiments of effort discounting, the reward recipients were exclusively the participants themselves. Sometimes, however, people may dedicate more effort not for themselves, but for someone else, for instance, significant others. In the present experiment, discounting of hyperbolic monetary reward by a job, handing out various number of advertising packs of tissues, was measured for each of 23 undergraduates when the recipient was the first dearest person (the #1 condition), the 20th dearest person (the #20 condition), a mere acquaintance (the #100 condition), or her/himself (the self-reward condition). Effort discounting rates for all four conditions were well described by hyperbolic functions (see Figure attached). The more social distance decreased, the shallower the effort discounting was. Interestingly, the steepness of effort discounting in the #1 condition was not significantly different from that in the self-reward condition, suggesting that people make effort for their intimates as they do for themselves.

Animals choose stimuli that precede preferred events to those that precede less preferred events. In contrast, stimuli that follow less preferred events are more preferable to those that follow more preferred events. The “work ethic effect” has been investigated in many studies, but some have failed to replicate it. It is possible that an important factor of the effect is to expose subjects to a strenuous schedule that results in energy expenditure. This study employed a reinforcement schedule in which the distance between operanda was manipulated as a response effort (Kono, The Psychological Record, in printing). In training, a simple simultaneous discrimination followed shorter response distance in an initial stimulus and a different simple simultaneous discrimination followed long response distance in the initial stimulus. During test trials, pigeons exhibited preference for stimuli that followed low effort schedules. The results were hence contrary to the predictions based on the work ethic effect.