Stimulus controllability and the latent inhibition effect

The effects of stimulus controllability on latent inhibition was examined in instrumental and classical conditioning. Rats allowed control over stimulus termination prior to avoidance conditioning exhibited no retardation of avoidance learning whereas subjects yoked to these rats with respect to pattern and amount of stimulus exposure but given no control over stimulus termination were retarded. However, groups of rats differentiated only by control over stimulus termination, prior to classical conditioning, were equally and severely retarded in the acquisition of a classically conditioned response as indexed by the CER technique. The results were discussed in terms of a learning hypothesis of latent inhibition.