Psychological Review >85 b> the American Psychological Association, Inc. 1985. Vol. 92. No. 3. 389-413 0033-205X/85/M0.75 Prime Theory: An Integrated View of Motivation and Emotion Ross Buck University of Connecticut Motivation and emotion are viewed as different aspects of a single process in which emotion involves the "readout" of motivational potential inherent in hierarchically organized primary motivational/emotional systems (primes). The most basic readout, Emotion 7, involves adaptive-homeostatic functions. In species where communication about the state of certain primes became important, Emotion II, involving their outward expression, evolved. With cognition, a third type of readout evolved, Emotion III, involving the direct experience of certain primes. A model of the interaction between primes and cognition is presented, and the unique role of language in human motivation-emotion is discussed. In recent years there has been a virtual models include that of Stellar (1954), which explosion of new information relevant to the posited specific drive systems for hunger, analysis of motivation and emotion that has thirst, and sex, based on excitatory and in- left attempts at theoretical integration far hibitory centers within the hypothalamus; behind. In the realm usually termed motiva- arousal theory (Hebb, 1955; Lindsley, 1957), tion, there has been increasing realization based on the brainstem reticular formation; that behavior can be initiated by external and the analyses of reward-punishment stimuli and cognitive processes as well as by mechanisms, beginning with J. Olds and Mil- the biological deficits that have served as the ner (1954). Each of these models has proved cornerstone of the drive-reduction model. useful and has gained some degree of empir- Mogenson and Phillips (1976) pointed out ical support, but none is sufficient to consti- that any contemporary analysis of motivation tute a general physiological model of moti- must account for behavior based on the ex- vation. pectation of reward (incentive motivation: At the same time, there have been events Bindra, 1968; Bolles, 1972) and for adaptive that have made the concept of emotion behavior that anticipates homeostatic deficits more acceptable to behaviorally oriented psy- before they occur. The apparent ability of chologists. Darwin's (1872/1965) theory in animals to make responses that anticipate Expression of the Emotions in Man and their needs suggests that they must use pro- Animals formed the basis of several proposi- cesses that "represent within the brain the tions that have gained considerable support: nature of the outside world" (Oatley, 1973, (a) Emotion is based on activity in neuro- p. 12). In this article I argue that such chemical systems in the central nervous sys- processes involve phenomena that have been tem, (b) these systems are the product of traditionally relegated to the realm of emo- evolution and reflect survival requirements tion. within each species, and (c) activity in these The major physiological models of moti- systems can be modified by learning. These vation have generally avoided the concept of basic elements appear in Tomkins's (1962, emotion, with its taint of subjectivism. These 1963) pioneering theory of affect, in Izard's (1971, 1977) evolutionary-develop- mental view of emotion, and in Ekman and I would like to thank a number of colleagues including Reuben Baron, Paul Ekman, Phoebe Ellsworth, several Friesen's (1969, 1975) neurocultural theory, anonymous reviewers, and particularly, Carroll Izard and and they are consistent with much recent the Editor for their valuable comments and suggestions work in ethology (Eibl-Eibesfeldt, 1970, 1972). on this article. These investigators have demonstrated that Requests for reprints should be sent to Ross Buck, Department of Communication Sciences, Box U-85, 850 the facial and gestural expressions associated Bolton Road, University of Connecticut, Starrs, Connec- with certain basic emotional/motivational ticut 06268. states or primary affects are widely generalized 389 390 ROSS BUCK within the human species, thus supporting a neocortex). More recent analyses of central major thesis of Darwin's. However, these nervous system mechanisms of emotion, such investigators have not considered the physio- as those of Gray (1982) and Panksepp (1981, logical bases of emotion in great detail, tend- 1982), can be viewed as progressive develop- ing to emphasize facial expression and other ments of this general line of reasoning. expressive movements in their studies of This article suggests a basis for integrating emotion. Also, they have typically emphasized these various views of motivation and emotion specific primary emotions or affects (such as in terms of a readout of information relevant Ekman's happiness, sadness, fear, anger, sur- to bodily adaptation and homeostasis (Buck, prise, disgust) as distinct from drives (hunger, 1980, 198la, 1984a, 1984b). It is not argued thirst, sex). that any of these views is incorrect, rather Another major type of approach to emotion that they are substantially correct as far as emphasizes the role of cognition in interaction they go, but that they are incomplete and with physiological factors. This approach has that it is possible to arrive at a comprehensive ties to the classical James-Lange theory of model of motivation and emotion by taking emotion (James, 1884), which posited that aspects of each of these views into account. the subjective experience of emotion involves The goal of this article is to present an the cognitive awareness of bodily responses. integrated way of thinking about motivation Schachter's (1964) self-attribution theory and and emotion in their various physiological, Lazarus's (1966) theory of coping have ana- expressive, and cognitive aspects. It is not my lyzed emotion in terms of the cognitive ap- intention to suggest specific hypotheses that praisal and labeling of external and internal derive from the present position or data that stimuli. Mandler (1975) and Averill (1980), would disconfirm it. I would hope instead among others, have expanded on this theme. that this position is judged by its ability to This approach is powerful and is able to serve as a metatheory, an integrative mecha- address a wide range of phenomena. However, nism to show the relation between theories as we shall see, it cannot easily deal with that are designed to handle more specific emotional phenomena that seem to be a ranges of phenomena. No new information product of brain activity alone. is being presented; rather, this is an attempt A third type of theory of emotion, empha- to organize concisely and efficiently what is sizing central nervous system mechanisms, known and, in so doing, to present a new derives from the classic position of W. B. and coherent way of looking at the phenom- Cannon (1927). In contrast with James, Can- ena of motivation and emotion. non argued that emotional stimuli cause brain This article is structured in a series of changes that, among other things, are a direct propositions with their associated reasoning source of subjective emotional experience. and documentation being relatively brief and Cannon suggested that emotional stimuli often limited to a few explanatory sentences cause subcortical systems to simultaneously with references. The intent is to present a and independently inform the cortex (result- general viewpoint without becoming involved ing in emotional experience) and the relevant with extended discussions of specific points. peripheral bodily systems (resulting in bodily responses). Papez (1937) suggested that the bodily response involves the hypothalamus, General Nature of Primary Motivational/ which controls the autonomic and endocrine Emotional Systems systems, whereas the experience of emotion involves the limbic system. MacLean (1968, 1970, 1973, 1981) later proposed the triune Biologically based primary motivational/ theory, which views the brain as a hierarchy emotional systems (primes) have evolved that has appeared successively over the course within each species with the basic role of of evolution: a reptilian portion (brain-stem, bodily adaptation and maintenance of ho- midbrain, and basal ganglia), a paleomam- meostasis. The common characteristics of malian portion (including the limbic system), primes may be summarized as follows: (a) and a neomammalian portion (including the They evolve according to requirements for MOTIVATION AND EMOTION 391 bodily adaptation and homeostasis, (b) they nal stimuli, including what have been termed involve active internal processes, (c) they tmpisms, taxes, endogenous automatic move- generally require internal or external stimuli ments, and reflexes (cf. Cofer & Appley, to become activated, (d) they are based on 1964). These are based on relatively simple innate mechanisms organized in the subcorti- neural systems and perform highly specific cal and paleocortical regions of the brain, functions vital to the organism. At a more and (e) they are special-purpose systems that complex level of organization, there are the serve a specific function in the species. These instincts or fixed action patterns, which in- characteristics are discussed in this section volve innate tendencies to perform specific and in the next two sections. actions. These involve a number of coordi- The term prime is suggested both because nating neural mechanisms culminating in an it serves as an acronym for the phrase primary orderly series of behaviors. These built-in motivational/emotional