Final answer:
Classical conditioning requires a neutral stimulus and an unconditioned stimulus to form associations. Through repeated pairings, the neutral stimulus becomes a conditioned stimulus, eventually eliciting the conditioned response.
Step-by-step explanation:
According to classical conditioning, two things are required for us to learn associations: a neutral stimulus (NS) and an unconditioned stimulus (US). In this learning process, a neutral stimulus is paired with an unconditioned stimulus. The neutral stimulus, which initially does not elicit any intrinsic response, eventually becomes a conditioned stimulus (CS) after repeated pairings with the unconditioned stimulus. As a result, the neutral stimulus begins to evoke a reaction similar to the unconditioned response, which is now called the conditioned response (CR).
For instance, in Ivan Pavlov's experiments with dogs, the sound of a bell (the neutral stimulus) was paired with the presentation of food (the unconditioned stimulus). After several pairings, the sound of the bell alone started to trigger salivation in the dogs, turning the bell into a conditioned stimulus and salivation in response to the bell into the conditioned response.
Two key processes in classical conditioning are acquisition and extinction. During acquisition, the association between the neutral stimulus and the unconditioned stimulus is established. Extinction occurs when the conditioned stimulus no longer predicts the unconditioned stimulus, leading to the weakening of the conditioned response.