Figure 4.4 | Positive and Negative Reinforcement and Punishment | “Positive” means that something is presented, and “negative” means that something is taken away. Reinforcement means that the behavior is strengthened, and punishment means that the behavior is weakened. In positive reinforcement, an appetitive (pleasant) stimulus is presented, and in positive punishment, an aversive (unpleasant) stimulus is presented. In negative reinforcement, an aversive stimulus is removed, and in negative punishment, an appetitive stimulus is removed.