Acquisition and extinction of an operant response in differentially reared rats.

Rats reared in either socially isolated or control environments were trained to bar press for food on a variable interval schedule of reinforcement, beginning at 125 days of age for 37 consecutive days. Following this phase the subjects were tested for response persistence during an extinction test. Next, the subjects were compared on measures of spontaneous recovery and the rate of response reacquisition when the reinforcement contingencies were once again reinstated. Though no differences were discerned between the groups on measures of acquisition, maintenance, and reacquisition, isolated rats emitted many more responses than the controls during extinction testing.