Imitation in Rats: Initial Responding and Transfer Evidence

Abstract

In two experiments, rats observed a conspecific demonstrator pushing a single manipulandum, a joystick, to the right or to the left for food reward before being given access to the joystick, for the first time, from a different orientation. In Experiment 1, rats that had observed left-pushing made more of their first three responses to the left than did rats that had observed right-pushing. In Experiment 2 the axis of joystick movement was rotated through 90° between observation and testing for half of the animals. These rats, like those that were tested with the joystick in the position it had occupied during demonstrator responding, showed a significant tendency to push the joystick in the same direction relative to their own bodies as had their demonstrators. These results, which cannot be explained in terms of stimulus-reinforcer learning, provide evidence that rats are capable of imitation, i.e. response, or response-reinforcer, learning by observation.