Contextual control over conditioned responding in a latent inhibition paradigm

We used 1-, 2-, and 3-context designs to study the control exerted by conte xts over freezing in rats exposed to a conditioned stimulus (CS) in advance of its pairing with a shock unconditioned stimulus. The latent inhibition observed when preexposure, conditioning, and testing occurred in the same c ontext was attenuated if preexposure occurred in a different context to con ditioning and testing. Latent inhibition (i.e., attenuated performance) was restored in a CS-specific manner if preexposure and testing occurred in th e same context and conditioning in a different one. Latent inhibition was a lso reduced by a long retention interval but remained specific for a partic ular context-CS relation. Finally, CS preexposure resulted in contextual co ntrol over the expression of excitatory conditioned performance. The result s are discussed in terms of memory, associative, and associative-performanc e models of CS-preexposure effects.