How does negative reinforcement differ from punishment in animal learning?

In the study of animal learning, the terms "positive" and "negative" do not denote value judgments but rather refer to whether a stimulus is added or removed. Both negative reinforcement and punishment are mechanisms of operant conditioning, but they serve opposite functions regarding behavior frequency.

• Negative Reinforcement: This is a behavior enhancer. It occurs when an annoying or harmful stimulus is removed or withheld specifically because the animal performed a desired action. By removing the unpleasant stimulus, the animal is encouraged to repeat the behavior in the future to avoid or escape that stimulus again.1
• Punishment: This is a behavior suppressor. It is used to discourage an undesired action. Punishment can be positive (adding a negative stimulus, such as an electric shock) or negative (removing a desired stimulus, such as food or privileges). Unlike reinforcement, which increases the likelihood of a behavior, punishment aims to decrease the frequency of an undesired behavior.12

While reinforcement strengthens a response, punishment inhibits it, often causing the animal to avoid the specific behavior or the environment where the punishment occurred.12