In a conditional discrimination each of two sample stimuli indicates which of two comparison stimuli is correct. When correct choice following each conditional stimulus is followed by a different outcome (one kind of food following one, a different kind of food following the other) it often facilitates acquisition and improves memory. In transfer designs, in which two different conditional discriminations are followed by the same two differential outcomes, outcome expectation can be shown to be sufficient for comparison choice. That is, the samples from one conditional discrimination are matched to comparisons from the other conditional discrimination based on the common outcomes alone. In the present study we asked if for pigeons the relative value of the differential outcomes (higher versus lower value) can serve as the basis for comparison choice, independent of other characteristics of the outcomes and of differential sample responding. That is, would different outcomes that could be described as "good" and "better" form two stimulus classes. For one conditional discrimination, the differential outcomes involved differential probability of reinforcement for choice of the correct comparison stimulus (0.80 vs. 0.20 for correct choice of the two comparisons, respectively). For the other conditional discrimination, the differential outcomes involved differential responding to the two comparison stimuli (5 pecks vs. 20 pecks to the correct comparisons, respectively). On test trials, when conditional stimuli from the two conditional discriminations were interchanged and the relative value of the differential outcomes could serve as the only basis for comparison choice, we found positive transfer. The results indicate that relational attributes of outcomes can serve as effective cues for comparison choice.
|Number of pages||7|
|State||Published - Feb 2010|
Bibliographical noteFunding Information:
Acknowledgments This research and the preparation of this manuscript were supported by National Institute of Mental Health Grant MH-077450 to the TRZ. We thank Mikael Molet for comments on an earlier version of this manuscript.
Copyright 2010 Elsevier B.V., All rights reserved.
- Categorical learning
- Differential comparison response
- Differential outcomes
- Relational learning
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Experimental and Cognitive Psychology