The effects of the interaction of reward-magnitude contrast and delay of reinforcement on odor production and utilization by the rat.

Abstract

Over the past fifteen years a considerable body of research has consistently demonstrated that albino rats exude odors as a function of experimental manipulations (i.e., reward and nonreward) in a variety of experimental situations, but especially in the straight runway maze apparatus. The aumulative findings of this research area indicate that odor production and/or utilizatjon js not constrained to elicit only innate responses. Odors can become discriminative stimuli which affect the behavior of conspecifics when such experimental measures as the hurdle-jump response, T-maze responding, escape from a compartment containing odors of conspecifics, and latency of responding in the straight runway apparatus are employed. A major focus of many of the investigations in this area has been to place the odor phenomena into an adequate theoretical framework. As such, frustration theory has been the most popular theoretical account employed, but this account has not adequately explained all of the relevant data. The purpose of the present study was to investigate the interaction of reward magnitude contrast and delay of reinforcement as it concerns the odor phenomena. Contrary to initial considerations, the results of the present experiment suggest that entrance into an empty goalbox is neither a sufficient nor necessary condition for the development of patterned responding in the straight runway. Conversely, the results showed that the presence of a single pellet in a goalbox can eliminate patterned responding under certain conditions. The results are discussed in terms of a frustration theory explanation, and possible modifications to that theory which could account for the present results.