Reinforcement, Positive and Negative

Reinforcement involves a stimulus change that occurs contingent on the performance of a target behavior and causes an increase in the future probability of that behavior. In positive reinforcement, the target response produces the addition of a stimulus (i.e., a positive reinforcer), whereas in negative reinforcement, it produces the removal of a stimulus (i.e., a negative reinforcer). Notably, reinforcement is defined by the effect of the procedure on future behavior. Only when a stimulus’s contingent delivery leads to an increase in the behavior can it be defined as a reinforcer. Reinforcers are often valued or liked by the individual, but this is not a necessary condition for a stimulus to be defined as such. Stimuli that serve as reinforcers based on an organism’s biological makeup ...