Sensorimotor modulation and the variable action pattern (VAP): Toward a noncircular definition of drive and motivation

Abstract

A definition of motivation is proposed which avoids two problems with earlier definitions in the psychological literature. It is nontrivial in that it distinguishes behavior for which a motivational construct is required from behavior that needs no such construct. It is noncircular in that it specifies motivational phenomena by both behavioral and physiological criteria. The modulation of stimulus-response efficacy is suggested as the defining property of motivational states; motivation is seen as altering the strength of, but not substituting for, environmental cues. Hormones and neuromodulators are suggested as the defining components of the mechanisms of motivational states. The fixed action pattern (FAP) of ethologists is designated as the unit of nonmotivated behavior; the variable action pattern (VAP) is designated as the unit of motivated behavior. This view treats hunger and thirst as special cases of motivation, rather than prototypes, and offers a common frame of reference for a wide range of motivations and emotions. © 1987, Psychonomic Society, Inc.. All rights reserved.