IMITIATION IN RATS - CONDITIONS OF OCCURRENCE IN A BIDIRECTIONAL CONTROL PROCEDURE

Magazine trained rats had their first opportunity to push a joystick i mmediately after observing the joystick being pushed to the right or t o the left by a conspecific demonstrator. When they were given direct access to the joystick, the observers were rewarded for both left and right pushes. Observers tended to push the joystick in the same direct ion as their demonstrators when the demonstrators' responses were imme diately followed by delivery of food to the demonstrator and the prese ntation of a tone, but no evidence of imitation was found when the dem onstrators' responses were followed by food alone, tone alone, or had no programmed consequences (Experiments 1 and 2). Imitative responding also occurred when the demonstrators' responses were partially reinfo rced with a programmed delay of 5 s between responding and food/tone d elivery (Experiment 3). These results suggest that, in this bidirectio nal control procedure, imitation will not occur unless the demonstrato rs' responses are followed (immediately or after a delay) by both a to ne and food. (C) 1994 Academic Press, Inc.