As an initial matter, it is important to define what is meant by reinforcement. The basic concept involves a change in an organism's surroundings that happens regularly when the organism responds in a given manner and which is known to increase the probability that the given response will be performed (Reinforcement, 2005: np). These surrounding variables are controlled or managed in order to study the effects of a particular type of reinforcement. It is not the organism which is being reinforced; instead it is the behavior which is the subject of the reinforcement, also known as operant conditioning (Michaels, 1975: 13). An early and authoritative statement defining reinforcement posited that,
example, food, water, sexual contact - to the situation. These we call positive reinforcers. Others consist of removing something - for example, a loud noise, a very bright light, extreme cold or heat, or electric shock - from the situation. These we call negative reinforcers. In both cases the effect of reinforcement is the same - the probability of response is increased. (Skinner, 1953: 73).
The most significant question is how to modify behavior by using reinforcement properly.