What is a primary reinforcer?

A primary reinforcer is a stimulus that is naturally rewarding, meaning it has inherent value and doesn't require any learning for its effectiveness. Examples of primary reinforcers include essential biological needs such as food, water, warmth, and shelter. These stimuli fulfill fundamental requirements for survival and are crucial in motivating behavior. For instance, when an animal is hungry, the presence of food will naturally reinforce behaviors that lead to obtaining that food because it satisfies the animal's need.

In contrast, other types of stimuli such as conditioned reinforcers rely on learning and association; for example, money is a secondary or conditioned reinforcer because it has no inherent value but represents the ability to obtain primary reinforcers. Other terms like negative reinforcement focus on the removal of an aversive stimulus to increase the likelihood of a behavior being repeated, which does not align with the definition of a primary reinforcer. Similarly, aversive consequences, used for punishment, work by discouraging unwanted behavior instead of promoting desirable behavior through rewards.