Rats respond for information: Metacognition in a rodent?

Abstract

In 2 experiments, rats were trained to press a centrally located lever that delivered immediate food reinforcement and turned on a light signal that indicated the location of a further food reward. After rats learned to press the lever and use the light cue to find food, immediate reinforcement for lever pressing was discontinued. In Experiment 1, rats continued to press the lever for information about the location of reward in a T-maze, but control groups yoked to the experimental group for amount of reward, and conditioned reinforcement showed complete extinction of lever pressing. Rats tested on an 8-arm radial maze in Experiment 2 also continued to press a lever that did not yield immediate reinforcement but provided a light cue indicating which randomly chosen arm of the maze contained food; lever pressing declined significantly, however, when the same arm contained food on every trial. Comparisons of testing conditions between and within experiments suggested that probability of lever pressing increased as the amount of information gained increased. The comparative implications of these findings for metacognition are discussed.