Contrasting AAC and ABC renewal: the role of context associations.

Rats were used in a lick suppression preparation to assess the contribution of conditioned-stimulus (CS)-context and context-unconditioned-stimulus (US) associations to experimental extinction. Experiment 1 investigated whether strengthening the CS-acquisition context association enhances extinction by determining whether stronger extinction is observed when CS-alone trials (i.e., extinction treatment) are administered in the acquisition context (AAC renewal), relative to a context that is neutral with respect to the US (ABC renewal). Less recovery of responding to the CS was observed in the former than in the latter case, extending the finding that AAC renewal is weaker than ABC renewal to our lick suppression preparation. Experiment 2 assessed the contribution of the acquisition context-US association to extinction of a CS by examining the effect of postextinction exposure to the acquisition context on responding to the extinguished CS. This manipulation enhanced responding to the extinguished CS in AAC, but not ABC, renewal. Experiment 3 addressed the contribution of the CS-acquisition context association by examining the potential of a neutral stimulus, presented in compound with the target CS during extinction treatment, to overshadow the CS-acquisition context association. This manipulation enhanced responding to the extinguished CS in AAC, but not ABC, renewal. The results stress the important role of contextual association in extinction and renewal.