Runway performance of rats for brain-stimulation or food reward: effects of hunger and priming

Abstract

In a runway paradigm, pretrial electric stimulation of the brain (ESB), food deprivation, and to a lesser extent water deprivation increased the running speed of rats to an ESB reward. The trial-by-trail course of the change in running speed after the manipulation of food deprivation resembled the steplike performance effect seen when pretrial priming ESB is changed rather than the incremental learning effect seen when the response contingent ESB is changed. In a second experiment, pretrial ESB enhance rats' performance for an ESB reward, but act in opposing directions rats' performance for a food reward. Implications for Deutsch's model of self-stimulation are discussed.