In classical conditioning, what does the term 'extinction' refer to?

In classical conditioning, extinction refers specifically to the process where the conditioned response gradually diminishes when the unconditioned stimulus is no longer presented alongside the conditioned stimulus. For example, if a dog has been conditioned to associate the sound of a bell (the conditioned stimulus) with food (the unconditioned stimulus), the dog will salivate at the sound of the bell. However, if the bell is sounded repeatedly without the presentation of food, the salivation response will weaken and eventually stop. This gradual decrease in response indicates that the association between the conditioned stimulus and unconditioned stimulus is weakening, resulting in extinction of the conditioned response.

The other options do not accurately capture this process: learning a new response pertains more to acquisition, while the continued presence of a stimulus after conditioning pertains more to habituation or maintenance of the conditioned response. Lastly, strengthening a conditioned response usually relates to concepts such as reinforcement, which is not involved in the extinction process. Understanding extinction is crucial for grasping how behaviors can diminish over time when the expected reinforcement (unconditioned stimulus) is absent.