Spontaneous Recovery

Abstract

Spontaneous recovery from extinction is one of the most basic phenomena of Pavlovian conditioning. Although it can be studied by using a variety of designs, some procedures are better than others for identifying the involvement of underlying learning processes. A wide range of different learning mechanisms has been suggested as being engaged by extinction, most of which have implications for the nature of spontaneous recovery. However, despite the centrality of the notion of spontaneous recovery to the understanding of extinction, the empirical literature on its determinants is relatively sparse and quite mixed. Its very ubiquity suggests that spontaneous recovery has multiple sources.Experimental extinction is one of the fundamental observations of Pavlovian conditioning. Just as the arranging of a positive relation between a conditioned stimulus (CS) and an unconditioned stimulus (US) produces acquisition of conditioned responding, breaking that relation produces extinction of that responding. However, similar to many terms in the behavioral sciences, the word "extinction" is used in at least three different senses: as a procedure, as a result, and as an explanation. If we are to understand extinction experiments, it is extremely important that we keep these senses distinct from each other.One use of the term is as an experimental procedure or independent variable under the control of the experimenter, as when one says, "Following learning, we subjected the animal to an extinction procedure." Most frequently, this is meant to refer to a procedure in which the original conditions of learning are disrupted. The most common extinction procedure consists of presenting a stimulus alone, so that it now fails to signal the outcome. However, other procedures, such as retaining the US but arranging for it to be independent of the CS are also available and of interest (see Rescorla 2001a).Another use of the term is as an experimental result or dependent variable under the control of the animal, as when one says, "When the stimulus was presented alone, the behavior extinguished." The prototypical example is one in which responding that was established by training deteriorates, often to a level such as that prior to learning.A third use of the term extinction is as a process or intervening variable that is intended to provide an explanation, as when one says, "When we arranged for the stimulus to be presented alone, the behavior deteriorated because of extinction." Normally, it is this process that is of interest. We would like to understand the basis of the change in behavior resulting from the change in procedure, whether that understanding is achieved at a conceptual or a neural level. Consequently, throughout this article the term extinction will refer to the learning process inferred when the procedure produces a particular result. When there is the possibility of misunderstanding, the phrase "extinction process" will be used.Because interest primarily centers on the learning process that occurs as a result of an ext...

Reconciling reinforcement learning models with behavioral extinction and renewal: Implications for addiction, relapse, and problem gambling.

“…This can also be seen in cued associations; animals are likely to "spontaneously recover" responding to a cue they have not been exposed to for a long time (Pavlov, 1927;Rescorla, 2004;Robbins, 1990). This cued renewal of responding is thought to underlie cued relapse to addiction (Childress, Ehrman, Rohsenow, Robbins, & O' Brien, 1992;Childress et al, 1993;Childress, McLellan, Ehrman, & O'Brien, 1988;O'Brien, Childress, McLellan, & Ehrman, 1992).…”

“…Current theories of extinction in both psychology and neuroscience (Bouton, 2002(Bouton, , 2004Bouton et al, 2006;Delameter, 2004;Milad & Quirk, 2002;Myers & Davis, 2002;Quirk et al, 2006;Rescorla, 2004) are based on the addition of new variables, often identified as contextual (Bouton, 2002(Bouton, , 2004Bouton et al, 2006) or inhibitory (Delameter, 2004;Pavlov, 1927). In any content-addressable memory, the cues provide inputs from which a unique state can be recalled.…”

“…Because the input weight matrix remains just below threshold, a single reward can retrigger responding (bringing it back above threshold). However, because the prediction unit waiting below threshold needs a positive ␦ signal to drive it back above threshold, the O'Reilly and Munakata model will not show a response to nonrewarded associated cues and cannot explain contextual or spontaneous recovery of responding (Bouton, 2002(Bouton, , 2004Rescorla, 2004;Robbins, 1990). Because extinction occurs by unlearning of the input weights to the prediction unit, extinction speed in the O'Reilly and Munakata model is inversely proportional to the partial reinforcement rate.…”

“…Reinstatement by provision of unsignaled rewards (Pavlov, 1927;Rescorla, 2004;Robbins, 1990) can also be envisioned as a cued recall of the original state over other states. The presence of recent/available rewards is one of the most salient differences between states (Capaldi, 1957(Capaldi, , 1958Capaldi & Birmingham, 1998;Capaldi & Lynch, 1968).…”

The exclusive induction of extinction is gated by BDNF

“…These factors would be expected to interact with each other such that the precise experimental conditions used by independent laboratories would differentially reveal recovery of the cued fear responses. Although most accounts of extinction and spontaneous recovery suggest that the original learning remains unchanged, there is ultimately a dissipation of the extinction memory at the behavioral level, the mechanisms underlying the loss of the extinction trace or its control over behavioral responses remain to be determined (for review, see Rescorla 2004). The durable extinction we show here may be a consequence of the context entering into primary excitatory and inhibitory associations with the US during conditioning and extinction, respectively.…”