International Journal of Comparative Psychology

Experiments designed to study latent inhibition typically use as a control condition a group of animals preexposed to the training context, but not to the conditioned stimulus (i.e., the context control). Experiments using the rat autoshaping preparation demonstrate that nonreinforced preexposure to the context facilitates subsequent conditioning to a discrete stimulus, particularly with large reinforcers (Experiment 1) and dramatically enhances performance under the unfavorable conditions posed by massed training (Experiment 2). Furthermore, it is nonreinforced preexposure to the training context, and not to a nontraining context, that enhances autoshaping performance (Experiment 3). The facilitatory effect of nonreinforced preexposure to the training context questions the exclusive use of the context control in latent inhibition experiments and suggests that findings based on such comparisons need to be reevaluated.