Reinforcement refers to a procedure or consequence that increases the frequency of the behavior immediately preceding it. If the behavior is already occurring at a high-frequency level, then the reinforcement maintains the behavior's frequency. If the consequence of the behavior makes the behavior occur more often or maintains it at its current rate, then the consequences are considered reinforcing. These reinforcers strengthen the behavior and make it more likely that the behavior will occur at some future point.
             There are two types of reinforcement. Positive reinforcement refers to consequences, which follow behavior and acts to strengthen that behavior. For example, reinforcement for completing all of a student's assignments may be that they get a free period at the end of the week to work on a project they would like to do, such as art. Negative reinforcement refers to the removal of a consequence, which serves to increase the frequency of the particular behavior. An example of negative reinforcement might be that a student gets detention for getting caught cheating on a test. The detention serves as a negative reinforcement to keep the student from doing the same thing in the future. Punishment and negative reinforcement are often confused. They differ, however, in that punishment is the presentation of an aversive event or removal of a positive reinforcement that results in a decrease in the frequency of a particular behavior.
             Extinction involves the cessation of reinforcement of a response. An example of extinction would be that you are having trouble in your biology class. You don't understand what the professor is saying during lectures and you are not sure what he wants from you on exams. You already have 2 D's on the exams. Three times you try to see him during office hours and every time he is not there. Eventually you stop trying to see him because of the repeated attempts failing. As children become so...