TEMPORAL FACTORS IN CLASSICAL-CONDITIONING

This paper addresses the role of temporal factors in classical conditioning and examines the assumption that temporal contiguity is the critical factor in the formation of an association between a conditioned stimulus (CS) and an unconditioned stimulus (US). First, the results of both delay and trace conditioning studies which have examined the effect of temporal variables are summarized. This body of work has shown that temporal contiguity is not a sufficient condition for the acquisition of conditioned responding. The US-US interval (cycle) and CS-US interval (trial) interact with each other to determine performance; the duration of the cycle relative to the trial is critical. Next, Gibbon and Balsam's (1981) application of Scalar Expectancy Theory (SET) to associative learning is presented and how this time-based comparator model accounts for various findings is discussed. In the final section, recent work on the role of temporal factors in a noncontingent procedure is presented. The results of this work have shown that the acquisition of responding depends on the duration of the period of nonreinforcement (CS-), rather than the cycle, relative to the trial, suggesting that the relevant comparator terms may need to be reconceptualized. A modified version of Gibbon and Balsam's original SET account is shown to handle these new findings and further implications of this modification are discussed. © 1991.