Renewal of instrumental avoidance in humans.

The ABA renewal effect occurs when behavior is trained in one context (A), extinguished in a second context (B), and the test occurs in the training context (A).Two mechanisms that explain ABA renewal are context summation at the test and contextual modulation of extinction learning, with the former being unlikely if both contexts have a similar associative history.In two experiments, we used within-subjects designs in which participants learned to avoid a loud noise (unconditioned stimulus) signaled by discrete visual stimuli (conditioned stimuli CSs), by pressing the space bar on the computer keyboard.The training was conducted in two contexts, with a different pair of CSs (CS+ and CS-) trained in each context.During extinction, CS+ and CS-stimuli were presented in the alternative context from that of training, and participants were allowed to freely respond, but no loud noise was presented.Finally, all CSs were tested in both contexts, resulting in a within-subjects ABA versus ABB comparison.Across experiments, participants increased avoidance responses during training and decreased them during extinction, although Experiment 2 revealed less extinction.During the test, responding was higher when CS+ were tested in the training context (ABA) versus the extinction context (ABB), revealing the renewal of instrumental avoidance.Experiment 2 also measured expectancy after the avoidance test and revealed a remarkable similarity between avoidance responses and expectancy ratings.This study shows the renewal of instrumental avoidance in humans, and the results suggest the operation of a modulatory role for the context in renewal, similar to the occasion setting of extinction learning by the context.