EFFECTS OF A DELAY‐REINFORCEMENT PROCEDURE ON PERFORMANCE UNDER IRT > t SCHEDULES 1

Water‐deprived rats were studied under a compound schedule that prescribed that responses terminating interresponse times (IRTs) greater than a fixed value t 1 . (IRT > t 1 component schedule) initiated a delay of reinforcement interval t 2 , at the end of which water was presented if the subject did not respond ( > t 2 component schedule). If the subject responded before the t 2 interval elapsed, the IRT > t 1 component schedule was re‐initiated and water was not presented. The IRT > t 1 and > t 2 component schedules were not differentially correlated with distinctive stimuli. Rate of responding during the IRT > t 1 component decreased as a function of the value of t 2 . The magnitude of the decreases in response rate appeared to be proportional to the subject's rate under the IRT > t schedule with no delay of reinforcement (t 2 = 0 sec). The effects were independent of the parameter value of the IRT > t 1 component schedule and of the rate of reinforcement. The results suggested that “efficiency” of performance under IRT > t schedules can be increased by appropriately arranging brief delays of reinforcement.