Pause relationships in multiple and chained fixed-ratio schedules

On a multiple fixed-ratio 10 fixed-ratio 100 schedule, pigeons pause for relatively long periods of time before the fixed-ratio 100 schedule. Only a short pause occurs before the fixed-ratio 10 schedule. A chain fixed-ratio 10 fixed-ratio 100 schedule produces the reverse pattern, i.e., a short pause before the fixed-ratio 100 schedule and a long pause before the fixed-ratio 10 schedule. Procedurally, the only difference between the two schedules is that the fixed-ratio 10 component is always terminated by some unconditioned reinforcer in the multiple schedule but never in the chained schedule. In the present experiment, the percentage of fixed-ratio 10 components which included reinforcement was gradually decreased for birds on the multiple schedule and gradually increased for birds on the chained schedule. It was found that percentage reinforcement within the fixed-ratio 10 component was inversely related to the duration of the pause before the fixed-ratio 10 component and directly related to the duration of the pause before the fixed-ratio 100 component. Thus, the relative rate of reinforcement paired with a particular stimulus was seen to be an important factor in determining response latency to that stimulus.