Transfer across drives of the discriminative effect of a Pavlovian conditioned stimulus.

Previous results suggest that a stimulus paired in Pavlovian fashion with reward should exert some discriminative control over an unrelated operant response acquired under a different drive-reward system. In the following experiment, a stimulus was first paired with food reinforcement for a hungry rat. Subsequently, the animal learned to lever-press for water reinforcements when thirsty but not hungry. Finally, the control over lever-pressing of the food-paired stimulus was tested by presenting it at various times during extinction of the lever-pressing response. All animals in the experiment showed the expected effect; each emitted more lever-presses during periods of the food-paired stimulus than during alternate control periods.