In classical conditioning, an unconditioned response (UCR) is a natural, automatic response that is elicited by an unconditioned stimulus. For example, in Pavlov’s experiment with dogs, salivating was the unconditioned response because it was a natural, automatic response to the food (the unconditioned stimulus). An unconditioned response is a response that has an innate, unlearned quality that makes it capable of being elicited by an unconditioned stimulus. It is contrasted with a conditioned response, which is a response that is elicited by a conditioned stimulus, which has been associated with the unconditioned stimulus through classical conditioning.
