Abstract
Rats were trained to bar press for food reinforcement in a two-bar multiple fixed-ratio situation. After the animal had established asymptotic rates of time for transferring between bars and responding on each bar, responding on one bar led to no reinforcement or random intermittent (50%) reinforcement. Responding on a second bar was always reinforced. Under both schedules of reinforcement, rats decreased their time to transfer to the second bar and their time to respond on the second bar. All animals also displayed an initial disruption of transfer back to and responses on the first bar. For rats on the intermittent reinforcement schedule, the decreased response time on the reinforced bar was primarily found after nonreinforcement of response to the previous bar. Reinforcement schedules for response to the first bar did not differentially affect the above behavior.