Contextual Control of Latent Inhibition by the Reinforcer

Abstract

Three experiments examined the contextual control of latent inhibition (LI) by the unconditioned stimulus (US) using a within-subjects conditioned suppression procedure with rats. The effect of reducing the context change produced by the introduction of the shock US was investigated by presenting this US during preexposure to the conditioned stimulus (CS). Although limited CS preexposure in the absence of the US had no impact on subsequent conditioning, preexposure in the presence of the shock retarded both excitatory and inhibitory conditioning. We conclude that the introduction of the US during the conditioning phase of a normal LI experiment can produce a contextual change that reduces the observed magnitude of LI.