Negative reinforcement seeks to promote a desirable behavior by removing an aversive stimulus while positive punishment seeks to stop an unwanted behavior by applying an aversive stimulus. In order to be effective, both forms of conditioning must be consistent and the stimuli must be adequately adapted to the behavior in question.
Negative reinforcement and positive punishment are opposites in both their objective and mechanism. Reinforcement encourages an action while punishment suppresses it. According to the University of Iowa's psychology department, reinforcement works by causing the subject to associate the desirable behavior with pleasure. An example of negative reinforcement is removing a child's television restriction if he cleans his room. This is in contrast to positive reinforcement, in which a desirable behavior is awarded with a pleasurable stimulus. An example is giving a dog a treat for performing a trick.
Punishment is intended to get rid of behavior. A positive punishment involves presenting the subject with something unwanted whenever he performs the undesirable behavior; for instance, handing out traffic tickets for speeding. Negative punishment involves taking something away, like confiscating a teenager's cell phone for staying out beyond curfew. Education-Portal.com states that members of the psychological community dispute the effectiveness of punishment, claiming that it only suppresses but does not eliminate undesirable behaviors. Drivers, for instance, do not internalize the principle of "no speeding." They learn to stay on the lookout for police and drive slowly only when they feel they are not being watched.