A MATCHING LAW ANALYSIS OF THE REINFORCING EFFICACY OF WHEEL RUNNING IN RATS

Previous research has demonstrated that running in a rotating wheel fu nctions as a reinforcer for leverpressing in rats. In these studies, t he pattern of responding was similar to the pattern of responding main tained by consummatory reinforcers, such as food and water. The presen t study investigated quantitative features of responding maintained by running. In previous experiments in which responses were reinforced a ccording to variable-interval (VI) schedules and food and water served as the reinforcer, the equation for a rectangular hyperbola described the relationship between response rate and reinforcement rate. This e xperiment tested whether this quantitative regularity also applies to leverpressing maintained by the opportunity to run in a wheel. Fourtee n male Wistar rats responded on levers for the opportunity to run. In each session, subjects were exposed to a series of VI schedules. An op portunity to run for 60 sec was the reinforcing consequence. Results s howed that response rate was a negatively accelerated function of rein forcement rate, and the relationship between these two variables was d escribed well by the equation for a rectangular hyperbola. To further test the similarity between running and consummatory reinforcers, the response requirement and access were manipulated. In previous experime nts with food and water, these types of manipulations differentially c hanged the two parameters of the hyperbola. A similar pattern of resul ts was obtained with wheel running. Thus, the equation appears to appl y to running about as well as it does to consummatory reinforcers.