Disinhibition and spontaneous recovery of response decrements produced by free reinforcement in rats.

Spontaneous recovery and disinhibition were studied in 3 experiments in which, after rats had been trained to bar press on a variable interval schedule of reinforcement, response rates were reduced by the introduction either of extinction or of a response-independent (free) reinforcement schedule. Spontaneous recovery was consistently obtained in extinction, especially when session durations were long. Under free reinforcement conditions there was little sign of spontaneous recovery, even when with high reinforcement rates response reduction was almost as rapid as in extinction. In disinhibition tests the introduction of noise produced increased responding under free reinforcement conditions, but not in extinction. The results are interpreted as demonstrating a dissociation between spontaneous recovery and disinhibition.