Primary Reinforcer

What is a primary reinforcer?

A primary reinforcer is a stimulus whose reinforcing effect does not require prior conditioning.

Primary reinforcer examples

Food and water are common examples under appropriate conditions. Their effects can depend on conditions such as hunger and thirst. Primary reinforcers are often used in operant conditioning, in which behavior changes as a function of its consequences. Whether a stimulus reinforces a particular behavior still requires observation.

Primary versus secondary reinforcers

The distinction concerns learning history: a primary reinforcer does not require prior conditioning, while a secondary, or conditioned, reinforcer acquires its reinforcing function through learning.

Source: Science and Human Behavior.