Reinforcement is any event or consequence that increases the likelihood that a behaviour will be repeated. It is a central concept in operant conditioning, developed by B. F. Skinner. Reinforcement can be positive, where a desirable stimulus is added, or negative, where an aversive stimulus is removed.

Primary reinforcers, such as food and water, satisfy basic biological needs. Secondary reinforcers, such as money, praise, and tokens, acquire their value through association with primary reinforcers. Reinforcement schedules—continuous or intermittent—strongly affect how quickly a behaviour is learned and how resistant it is to extinction.

Types

• Positive reinforcement: add something pleasant
• Negative reinforcement: remove something unpleasant
• Primary reinforcers: innate, biological
• Secondary reinforcers: learned, associated