Classical-classical transfer: Excitatory associations between “competing” motivational stimuli during classical conditioning of the rabbit

A sensory preconditioning analogue was employed to separate signaling effects from motivational effects observed in appetitive-to-aversive transfer of training. Rabbits received appetitive conditioning (tone-water pairings) of the jaw-movement response, followed by aversive conditioning of the nictitating membrane response, during which water delivery served as the CS for para-orbital shock. When the tone was subsequently presented, only subjects exposed to both sets of pairings demonstrated conditioned jaw movement and nictitating membrane responses. The occurrence of both responses to the tone is inconsistent with the action of reciprocal inhibition between motivational states. The results are interpreted in terms of multiple mediators for transfer-of-training paradigms.