CODING OF HEDONIC AND NONHEDONIC SAMPLES BY PIGEONS IN MANY-TO-ONE DELAYED MATCHING

In two experiments, pigeons were trained on many-to-one delayed matchi ng in which samples of food and one hue were each associated with one shape comparison, and samples of no food and a different hue were each associated with a second shape comparison. When later tested with del ays between sample and comparison stimuli, pigeons showed nonparallel delay functions, typically found with food and no-food samples (i.e., steeply declining food-sample delay functions, and relatively flat no- food-sample delay functions). Furthermore, the slopes of the hue-sampl e delay functions were similar to those on the food/no-food-sample tri als. In Experiment 2, following many-to-one delayed matching, when the hue samples were associated with new comparisons and then food and no -food samples replaced the hues, evidence was found for transfer of tr aining indicative of the common coding of samples associated with the same comparison in original training. The transfer results suggest tha t the asymmetrical hue-sample functions resulted from the common codin g of samples associated with the same comparison.