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Abstract The present study evaluated the role of inhibition in paradoxical choice in pigeons. In a paradoxical choice procedure, pigeons receive a choice between two alternatives. Choosing the “suboptimal” alternative is followed 20% of the time by one cue (the S+) that is always reinforced, and 80% of the time by another cue (S-) that is never reinforced. Thus, this alternative leads to an overall reinforcement rate of 20%. Choosing the “optimal” alternative, however, is followed by one of two cues (S3 or S4), each reinforced 50% of the time. Thus, this alternative leads to an overall reinforcement rate of 50%. González and Blaisdell (2021) reported that development of paradoxical choice was positively correlated to the development of inhibition to the S- (signal that no food will be delivered on that trial) post-choice stimulus. The current experiment tested the hypothesis that inhibition to a post-choice stimulus is causally related to suboptimal preference. Following acquisition of suboptimal preference, pigeons received two manipulations: in one condition one of the cues in the optimal alternative (S4) was extinguished and, in another condition, the S- cue was partially reinforced. When tested on the choice task afterward, both manipulations resulted in a decrement in suboptimal preference. This result is paradoxical given that both manipulations made the suboptimal alternative the richer option. We discuss the implications of our results, arguing that inhibition of a post-choice cue increases attraction to or value of that choice.
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Pigeons (Columba livia) distinguish between absence of events and lack of evidence in contingency learning
When information about an event is perceptually occluded, individuals might recognize that the event may be present but that they cannot detect it because of the occluder. In such situations, an individual should continue to believe that the prevailing contingencies have not changed. This is in stark contrast to conditions where an expected event is explicitly absent, which should lead the individual to update their contingency knowledge. In an autoshaping procedure, we tested whether pigeons can discriminate conditions of perceptual ambiguity from perceptual certainty. Pigeons first learned to peck at two Pavlovian visual cues, followed by extinction of one of the cues. During extinction, the feeder was occluded by a metal shield for pigeons in Group Occluded, while the metal shield was placed next to but not covering the feeder for pigeons in Group Un-Occluded. On a final test with the metal shield removed, pigeons in Group Un-occluded pecked less at the extinguished cue than at the un-extinguished cue; while pigeons in Group Occluded pecked at an equally high rate to both cues. These results replicate in pigeons with similar results reported in rats by Waldmann et al. (2012) and show that pigeons are able to discriminate conditions of certainty from conditions of ambiguity.
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- Award ID(s):
- 1844144
- PAR ID:
- 10476458
- Publisher / Repository:
- International Society for Comparative Psychology
- Date Published:
- Journal Name:
- International Journal of Comparative Psychology
- ISSN:
- 0889-3675
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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