Sources of relapse after extinction in Pavlovian and instrumental learning
Extinction may be related to therapeutic procedures designed to eliminate unwanted thoughts, emotions, or behaviors. This article reviews animal learning research which suggests that extinction does not erase the original learning, but rather makes behavior especially sensitive to background, or context, in which it occurs. Context-dependence of responding is evidence after extinction in both Pavlovian and instrumental (operant) learning. In either case, memories of conditioning and extinction are both retained through extinction, and are available for retrieval by appropriate retrieval cues. When the context promotes retrieval of extinciton, extinction performance is observed. But when the context is changed, or when the current context promotes retrieval of conditioning, conditioning performance is often restored. These effects are produced by context provided by stimuli as diverse as physical environments, reinforcer after-effects, drug states, emotions, and the passage of time. The results have implication for relapse, and its prevention, following therapy.