The effect of two schedules of primary and conditioned reinforcement.

Of 23 pigeons, 11 received continuous reinforcement for key pecking, and 12 received an FR 10 schedule of reinforcement. The birds were then tested without food, but with potential conditioned reinforcers presented either on the same schedule as in training, on the other schedule, or not at all. Each bird in the subgroup trained on CRF and tested with S(r)'s at FR 10 not only gave more responses in testing than did each bird in both subgroups receiving no S(r)'s, but also gave more responses than did each bird in the S(r) subgroup receiving CRF training and S(r)'s at CRF. Cumulative records are presented to show the effects of different schedules of conditioned reinforcers.