The role of the flavor cue not paired with large reward in within-subjects negative anticipatory consummatory contrast

Joan Denise Sheffer, Purdue University

Abstract

Three experiments examined the role of the flavor cue not paired with large reward in the within-subjects negative anticipatory contrast procedure. One flavor-small reward (flavor 1) precedes a reinforcer that is larger than the reinforcer preceded by a second flavor-small reward (flavor 2). Negative anticipatory contrast is defined by suppressed consumption of the flavor that precedes the larger reinforcer relative to consumption of the other flavor. Flavor 1-small reward is followed by a larger reward (sucrose), whereas flavor 2-small reward is not, resulting in suppressed consumption of flavor 1. Sometimes rats consume more, not less, of the flavor that precedes the larger reinforcer, and prefer this flavor in a subsequent test. These experiments show that varying the consequent of flavor 2 influences the degree of preference conditioning to flavor 1. A small reward, no reward and empty tube were used as consequents for flavor 2. These three consequents are all smaller rewards than the large reward but were shown to differ in degree. In Experiment 1, rats preferred flavor 1 to flavor 2 more if flavor 2 was followed by saccharin than if it was followed by nothing. This greater preference for flavor 1 was suggested to be due to flavor 2 preceding the unsatisfied post-ingestive effects of consuming saccharin alone. In Experiment 2, presentation of an empty tube controlled consummatory behavior and, therefore, served as the absence of a substance in a between-subjects negative anticipatory contrast paradigm employing partial reward. Experiment 3 employed the empty tube as a consequence for flavor 2 in the within-subjects negative anticipatory contrast procedure. Rats preferred flavor 1 to flavor 2 when flavor 2 was followed by saccharin, nothing, or an empty tube and the difference was greater for those that received the empty tube. The saccharin consequent had more value than the empty tube consequent suggesting saccharin has some rewarding properties in the anticipatory contrast procedure. This paper offers an alternative analysis to Lucas and Timberlake's (1992) to account for the production of preference conditioning in the within-subjects anticipatory contrast procedure.

Degree

Ph.D.

Advisors

Capaldi, Purdue University.

Subject Area

Psychology|Experiments

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