Which concept is NOT directly related to classical conditioning?

Reinforcement is a key concept in operant conditioning, which is distinct from classical conditioning. In operant conditioning, behaviors are strengthened or weakened through the use of reinforcements or punishments, which work on the principle of consequences following a behavior. On the other hand, classical conditioning, as originally demonstrated by Ivan Pavlov, involves forming associations between stimuli, typically starting with an unconditional stimulus that naturally and unconditionally produces a response, such as salivation in dogs.

In classical conditioning, the unconditional response (the natural reaction to the unconditional stimulus), conditioned stimulus (a previously neutral stimulus that, after being paired with the unconditional stimulus, elicits a conditioned response), and neutral stimulus (a stimulus that initially does not elicit a response until paired with the unconditional stimulus) are all integral components of the process. Thus, while reinforcement applies to the learning principles seen in operant conditioning, it does not play a role in the classical conditioning framework.