A contingency can be either a reinforcement or punishment that occurs after a behavior has been expressed by an individual or group.  A naturally existing contingency, in layman’s terms, “natural consequence” happens without the manipulation of the behavioral analysts.  Such an example would be, hitting the snooze button makes you late for work which causes you to leave your house without the opportunity for breakfast.  The punishment of not having access to breakfast is the naturally existing contingency for hitting the snooze button.

A contrived contingency is a reinforcement or punishment that is implemented by a teacher in order to encourage behavior change or skill acquisition.  An example of this would be giving a child access to a preferred toy after finishing a puzzle.

Non-contingent reinforcement (NCR) involves giving reinforcement on a regular schedule regardless of behavior.  The attempt is to reduce the problem behavior by providing the reinforcer freely, without contingencies, so that the motivation to engage in the problem behavior is reduced. NCT is a manipulation of motivating operations, creating an abolishing operation (AO) and a situation of reinforcement satiation. If one has identified that the function of a behavior is for attention, for example, we could try to reduce the behavior by giving attention on a regular schedule and reducing the motivation to get it through the behavior.

An indiscriminate contingency is the reinforcement rate decreasing to the one that is naturally available.  In order to test for generalization, one would reduce the reinforcement rate to an indiscriminable contingency.  The learner should not need any prompts or continuous reinforcement during generalization, and the indiscriminate contingency available should be enough to maintain the behavior.

4 term contingency is EO -> Sd-> Response and Reinforcement