Final answer:
Spontaneous recovery is the phenomenon where an extinguished conditioned response re-emerges after a period with no exposure to the conditioned stimulus.
Step-by-step explanation:
When a behavior that has been extinguished (or reduced following extinction) re-emerges after a period of no exposure to the conditioned stimulus, this phenomenon is called spontaneous recovery. This differs from an extinction burst, which refers to a temporary increase in the frequency or intensity of the extinguished behavior when extinction first begins. In the context of classical conditioning, if a conditioned stimulus (like the sound of a bell for Pavlov's dogs) is repeatedly presented without the unconditioned stimulus (meat powder), the conditioned response (salivating) will eventually stop, which is known as extinction.
However, after some time has passed without any further conditioning trials, the conditioned response can suddenly reappear upon presenting the conditioned stimulus again; this is an example of spontaneous recovery. Similarly, in operant conditioning, a behavior that was previously reinforced and then stopped might also reappear the next time a reinforcement opportunity is presented, indicating the same concept of spontaneous recovery.