Same/Different Reversal Learning in Pigeons (Columba livia)
Abstract
Reversal learning is a common procedure for studying discrimination learning, but has yet to be studied in a same/different abstract-concept learning task. In the present study, the ability to learn a same/different task with repeated contingency reversals was assessed in 4 pigeons with extensive experience in a two-item same/different task. Subjects were shown a sample picture and required peck the stimulus a Fixed-Ratio 14 (FR 14), then, simultaneously presented below the sample, another picture and a white rectangle. If the two pictures were the same, the correct response was to touch the lower picture. If the two pictures were different, the correct response was to touch the rectangle. Once steady-state performance was obtained, the contingencies were reversed such that if the two pictures were the same, the correct response was to touch the rectangle. If the two pictures were different, the correct response was to touch the lower picture. Upon reaching criterion, a reversal back to the initial contingency was implemented and followed by subsequent repeated contingency reversals. After 12 such reversals, a transfer test was given to assess discrimination of novel stimuli. The results indicate subjects’ can flexibly learn reversals and transfer to novel stimuli. Given the successful full transfer, performance is interpreted to characterize relational rule use in an abstract-concept learning task with reversals.