Data set for "When a stay is a switch: Discriminative control of response chunks determines preference during concurrent VI VI schedules"

We present evidence that changeover delays (CODs) create response chunks and that the discriminative control of these units contributes to observed preference during concurrent variable-interval (VI) VI schedules of reinforcement. Two experiments were conducted with pigeons. Both utilized multiple VI 30-s VI 60-s, VI 30-s VI 60-s schedules of reinforcement. One of the VI 30-s schedules was further paired with a 2.5-s changeover delay (COD). After training, unreinforced probes trials were conducted that paired the two stimuli associated with the VI 30-s schedules. In both experiments, during training, birds showed a preference for the VI 30-s schedule over the VI 60-s schedule. This preference was more extreme for the schedule pair in which a COD was programmed with the VI 30-s schedule. Further, an analysis of molecular response patterns found that the application of a COD led to discrete bursts of rapid responding when birds first switched into the VI 30-s schedule. This burst was not observed at the VI 30-s schedule in which no COD was assigned. Finally, during probes we observed a preference for the VI 30-s stimulus associated with a COD, but only when our probes maintained discriminative control of response bursts. Without this discriminative control, preference was reversed, mirroring the local reinforcement rates obtained during training.