Effects of concurrent exposure to different food and sucrose rewards in differential conditioning

Abstract

In one experiment two control groups were run to either an eight-pellet reward or a one-pellet reward and a discrimination group was run to eight pellets on one stimulus and one pellet on a second stimulus. The discrimination group ran slower to the one-pellet stimulus than did the low-reward control group, indicating the presence of a concurrent depression effect. In the second experiment the same design was used but a high sucrose reward was contrasted with a low sucrose reward. The rate of differentiation was retarded in the sucrose experiment compared to the food pellet experiment and no depression effect was observed, although the functional difference between the sucrose rewards was greater than between the food pellet rewards. These data indicate that the difference between sucrose and food pellet rewards obtained in sequential shift experiments is also obtained in concurrent shift experiments.