Evaluation during the extinction procedure causes extinction in evaluative conditioning

After repeated pairing of a neutral stimulus (the conditioned stimulus or CS) and an affective event (the unconditioned stimulus or US), the stimulus can elicit responses that are evoked by the affective event. The acquired response decreases throughout solo presentations of a stimulus, which is known as extinction. Evaluative conditioning (EC) experiments have showed both extinction and resistance to extinction, while Pavlovian conditioning (PC) experiments have usually showed extinction. The present study hypothesized that repeated evaluation during the extinction procedure develops inhibitory learning of stimulus-response relationships then causes extinction, based on the inhibitory learning perspective of PC. Four experiments examined the effect of repeated evaluation while eliminating alternative explanations other than inhibitory learning, i.e., local CS-US contingency and contextual discriminability (Experiment 2); attention to CS, prolonged time, and additional CS presentations (Experiment 3); and inhibition of the output response and forgetting (Experiment 4). The results demonstrated extinction as well as resistance to extinction, consistent with the hypothesis. Possible content of the inhibitory learning as well as how it explains the extinction phenomenon in EC are discussed.