Conditioned Inhibition and Excitation in Operant Discrimination Learning

Abstract

Pavlov’s procedure for demonstrating conditioned Inhibition was applied to the case of a discriminated operant to see whether a parallel exists in the operant case. A stimulus (tone) that had become a signal for not responding when paired with one excitatory stimulus (key-color used in conjunction with a go/no-go auditory discrimination) also served as a signal for not responding when it was combined with another excitatory stimulus (key-color used for transfer test) that was clearly discriminated from the one employed in the original training. Skinner’s injections to Pavlov’s demonstration of conditioned inhibition were shown not to apply to the present experiment. A second experiment showed that training of a kind that led to a conditioned inhibitory function for a stimulus paired with nonreinforcement can also lead to a conditioned excitatory function for a stimulus paired with reinforcement. Appropriate controls made it evident that these results were not due to unconditioned effects of tone. When training and testing procedures which parallel those used in classical conditioning are applied to the discriminated operant, the functions of stimuli in the two types of conditioning prove to be more similar than was previously thought.