United Kingdom Subway Map on reinforcement n. in operant conditioning, a process in which the frequency or probability of a response is increased by a dependent relationship, or contingency, with a stimulus or circumstance (the reinforcer). reinforcement contingency the contingency (relationship) between a response and a reinforcer. The contingency may be positive (if the occurrence of the reinforcer is more probable after the response) or negative (if it is less probable given the response). Reinforcement contingencies can be arranged by establishing dependencies between a particular type of response and a reinforcer (as when an experimenter arranges that a rat’s lever presses are followed by presentation of food), or they can occur as natural consequences of a response (as when a door opens when pushed), or they can occur by accident. reinforcement schedule see schedule of reinforcement. reinforcer n. United Kingdom Subway Map 2016.