Motivação e análise do comportamento

A discriminative stimulus is a stimulus condition which, (1) given the momentary effectiveness of some particular type of reinforcement (2) increases the frequency of a particular type of response (3) because that stimulus condition has been correlated with an increase in the frequency with which that type of response has been followed by that type of reinforcement. Operations such as deprivation have two different effects on behavior. One is to increase the effectiveness of some object or event as reinforcement, and the other is to evoke the behavior that has in the past been followed by that object or event. "Establishing operation" is suggested as a general term for operations having these two effects. A number of situations involve what is generally assumed to be a discriminative stimulus relation, but with the third defining characteristic of the discriminative stimulus absent. Here the stimulus change functions more like an establishing operation than a discriminative stimulus, and the new term, "establishing stimulus," is suggested. There are three other possible approaches to this terminological problem, but none are entirely satisfactory.

The first two books on behavior analysis (Skinner, 1938; Keller & Schoenfeld, 1950) had chapter-length coverage of motivation. The next generation of texts also had chapters on the topic, but by the late 1960s it was no longer being given much treatment in the behavior-analytic literature. The present failure to deal with the topic leaves a gap in our understanding of operant functional relations. A partial solution is to reintroduce the concept of the establishing operation, defined as an environmental event, operation, or stimulus condition that affects an organism by momentarily altering (a) the reinforcing effectiveness of other events and (b) the frequency of occurrence of that part of the organism's repertoire relevant to those events as consequences. Discriminative and motivative variables can be distinguished as follows: The former are related to the differential availability of an effective form of reinforcement given a particular type of behavior; the latter are related to the differential reinforcing effectiveness of environmental events. An important distinction can also be made between unconditioned establishing operations (UEOs), such as food deprivation and painful stimulation, and conditioned establishing operations (CEOs) that depend on the learning history of the organism. One type of CEO is a stimulus that has simply been paired with a UEO and as a result may take on some of the motivative properties of that UEO. The warning stimulus in avoidance procedures is another important type of CEO referred to as reflexive because it establishes its own termination as a form of reinforcement and evokes the behavior that has accomplished such termination. Another CEO is closely related to the concept of conditional conditioned reinforcement and is referred to as a transitive CEO, because it establishes some other stimulus as a form of effective reinforcement and evokes the behavior that has produced that other stimulus. The multiple control of human behavior is very common, and is often quite complex. An understanding of unlearned and learned establishing operations can contribute to our ability to identify and control the various components of such multiple determination.