Drives

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Drives

I. Physiological DrivesPaul Thomas Young

BIBLIOGRAPHY

II. Acquired DrivesJudson S. Brown

BIBLIOGRAPHY

I PHYSIOLOGICAL DRIVES

Physiological drives are regarded as persisting, organic motivations: conditions that arouse, sustain, and regulate human and animal behavior. Insofar as drives are based upon metabolic conditions they are common to all men in all societies and to many animals. Examples of drives originating in metabolic conditions are: general hunger, specific food appetites, thirst, air hunger, the urges to uri-nate and defecate, the urge to maintain a constant internal temperature and to sleep, to rest when fatigued, to be active when rested.

Carl J. Warden defined “drive” empirically as persisting goal-oriented behavior, and he measured the strength of hunger, thirst, sex, maternal, and exploratory drives by observing the frequency with which a rat approached and crossed a charged grille to reach an incentive object: food, water, mate, etc. Most psychologists, however, regard drive as an explanatory concept. Behavior is driven by certain internal conditions called drives; drive is a hypothetical construct employed to explain activity.

Physiological drives must be distinguished from external determinants, including the whole gamut of social goals, interests, values, attitudes, and personality traits. When, for example, Buddhist monks in Vietnam committed suicide by burning, their motivation was derived from their complex social situation and not from physiological drives.

Drive versus drives

The term “drive” was introduced to American psychology by Robert S. Wood-worth in 1918. He derived the term from mechanics rather than biology. A machine, he claimed, is a mechanism that can accomplish work only if there are energy transformations within its parts. The drive of a machine is the physical energy that makes it go.

Following Woodworth, other psychologists (Fred A. Moss, John F. Dashiell, Edward C. Tolman, Curt P. Richter, Carl J. Warden, Calvin P. Stone, and others) adopted the term but began experimenting with drives (in the plural), such as the hunger, thirst, and sex drives. These drives were not distinguished as forms of physical energy (mechanical, thermal, electrical, chemical, photic) but, rather, in terms of the external and bodily conditions that underlie and regulate behavior.

Energizing and regulating functions

Some psychologists restrict the concept of drive to the energetic aspect of motivation. Judson S. Brown (1961) clearly distinguished drive as an energizing function from the functions of directing and regulating behavior. Regulation is thought to be accomplished by associative bonds, habit systems, innate structures. Drive stimuli originate in tissue conditions and as stimuli they have a common energizing function. Brown wrote of different sources of drive rather than of different drives. Again, Elizabeth Duffy distinguished between the activating and directing aspects of motivation. She identified drive with activation and defined it in terms of energy potentially available for behavior (1962, p. 17).

The distinction between energizing and regulating functions is of prime importance in any definition of the drive concept. But since energy transformations always occur within bodily mechanisms and since these mechanisms regulate the pattern and direction of activity, it is difficult, if not impossible, to consider energizing apart from bodily structures.

The stimulation theory of drive

In the writings of Clark L. Hull, drive (D) is a nonspecific energizing factor that can raise the excitatory potential of various habits (1943). In addition to D, Hull postulated various specific drive stimuli (symbolized by Sd or Ds) arising from tissue needs. Sd strengthens only those responses that are relevant to satisfying a specific need, but D strengthens all responses that happen to be aroused when D is present [seeHull].

Some behavior theorists, for example, Neal Miller and Kenneth W. Spence, have staunchly supported Hull’s postulate of two drive factors— general drive and specific drives—but others have questioned the need for a nonspecific drive factor. Thus, Edwin R. Guthrie argued that the concept of stimulus is fully adequate to account for all drives. A persisting stimulus from a tense bladder, he wrote, is adequately described as a stimulus and nothing is gained by designating it a drive. William K. Estes (1958) wrote that drive stimuli are similar to all other stimuli, and he suggested that selective behavior can be explained without the benefit of a nonspecific, energizing drive factor. Robert C. Bolles (1958), after reviewing the positions taken by behavior theorists, questioned the utility of the drive concept. Use of the drive concept, he wrote, reflects an ignorance of the stimulus; if more were known about the stimuli associated with each specific drive, one could dispense with a general non-specific drive factor [seeGuthrie].

Despite these views, there is sound physiological evidence, as Donald O. Hebb has pointed out (1955), for the existence of a general, nonspecific factor of arousal or activation. The evidence will be considered below [seeStimulation drives].

Chemical motivation

Every theory of drive must take account of persisting chemical sensitizers, excitants, inhibitors, and tranquilizers that act directly upon neural centers. A single example of hormonal control will illustrate the nature of chemical motivation:

In a series of studies upon male sexual behavior, Frank A. Beach demonstrated a positive relation between the rat’s sexual reaction to an estrous female and his speed of locomotion to the goal box in which she is held. The active males, after demonstrating normal sexual activity, were castrated. Following the operation there was a gradual loss of sexual ability, shown by decrease in the intensity, completeness, and frequency of mating responses and by a steady lengthening of the time required to traverse a runway to reach a mate. Copulatory responses were finally abolished, and many males remained in the starting box, failing to enter the runway. At this stage of the experiment the inactive males were given daily injections of testosterone propionate. While injections continued there was an increase in sexual reactions to the estrous female and a steady decrease in the time required to reach the goal box. The experiment (Beach 1956, p. 12) clearly demonstrated the importance of hormonal factors in maintaining sexual responsiveness.

Homeostatic needs and drives

Claude Bernard pointed out that the cells of the body can survive only if the fluid matrix within which they exist remains relatively stable in its physical and chemical constitution. Following Bernard, Walter B. Cannon coined the term “homeostasis” to designate the steady physical state essential to life. Within the blood, for example, there are homeostases of oxygen content, water content, temperature, acidity, glucose, fat, proteins, and calcium, sodium, and other minerals.

The principle of homeostasis provides an important basis for defining objectively the metabolic needs of men and animals. To maintain homeostasis an organism needs (requires) certain nutritive substances: oxygen, water, proteins, fat, carbohydrate, minerals, and vitamins. Also, an organism needs to maintain a constant internal temperature despite wide variations in external temperature [seeHomeostasis].

Some psychologists have equated needs and drives, but the concepts are distinct. Homeostatic needs may affect growth, reproduction, metabolism, and health with little or no influence upon behavior.

Curt P. Richter extended the homeostatic doctrine by showing ways in which behavior aids the organism in maintaining homeostasis (1943 ). When homeostasis is disturbed, he pointed out, behavior compensates to restore a steady state. To illustrate: If the adrenal glands of rats are surgically removed, the adrenalectomized animals die in 10 to 15 days as a result of loss of sodium chloride through the urine. But if the operated rats are given free access to a 3 per cent sodium chloride solution, they ingest several times the normal amount of salty fluid and survive indefinitely in seemingly good health. The increased appetite for salt serves to maintain homeostasis and to preserve life. Richter (1943) believed that the effort to maintain homeostasis is one of the most universal and powerful of all behavioral urges, or drives, in animals and human beings.

Other psychologists have extended the homeostatic doctrine far beyond its physiological limits. Attempts have been made to extend the doctrine to the maintenance of stability within the social order, to the perceptual constancies of the physical and social worlds, to constancies in personality, and to psychophysical judgments. It seems preferable, however, to hold to the original physiological meaning of homeostasis and to use some other concept, for example, adjustment, in considering the dynamic relations between an organism and its environment. [See Perception, article onPerceptual constancy.]

The homeostatic doctrine has met with a good many criticisms. For example, in a review of the literature on thirst, Lawrence I. O’Kelly (1963) pointed out that the homeostatic doctrine does not greatly help a physiologist who is dealing with the specific processes that regulate body water. It is difficult to identify thirst with any one specific bodily event. What is needed is patient collection of empirical data rather than speculation about a homeostatic thirst drive.

Motivation and functional capacity

Robert S. Woodworth (1958) argued that when an active organism is dealing with its environment, no extrinsic drive is required to explain activity. The organism observes, explores, manipulates, and studies its environmental surroundings with intrinsic motivation.

Behavior manifests the innate capacities of the creature. The bird is hatched with an innate capacity to fly. From this fact one can safely predict that the bird will fly. The young bird, in fact, makes considerable progress in mastering its mode of locomotion before using this skill in hunting food. The creature exercises its capacity to fly first for its own sake and later in the service of food seeking. Again, the chimpanzee has considerable inclination to climb trees and to brachiate—a performance for which he has considerable talent thanks to his bodily proportions and lever systems, bones, tendons, and muscular and nervous structures.

Henry W. Nissen (1954), Robert W. White (1959), Daniel E. Berlyne (1960), and others argued that human sense organs, muscles, and brain have the functional capacity to observe, explore, manipulate, test, reflect, think. These innate structures require activity for health and growth. No extrinsic motivation is needed to explain the functioning of an active human brain. Man, in fact, seeks stimulation. He rides a roller coaster, engages in dangerous sports, plays games that involve risk and suspense, works endlessly to solve puzzles. The motivation is neurogenic, and the patterns of behavior are regulated according to a structure–function principle.

White emphasized the human tendency to acquire competence in dealing with the environment. Underlying this tendency is a form of motivation he labeled effectance. Effectance motivation is selective, directed, persistent. Its energies are neurogenic, being the energies of the living, active cells that make up the nervous system.

Similar views have been expressed by Harry F. Harlow, who demonstrated that manipulative and exploratory behavior does not depend on homeostatic drives, and by Gordon W. Allport in his doctrine of the functional autonomy of motives [seePersonality: contemporary viewpoints].

Neurogenic drive

Under the influence of classical associationism and the stimulus–response formula an organism was regarded as a passive structure aroused to action by hunger, thirst, pain, sexual stimulation, and other primary drives and, secondarily, by acquired drives associated with these primary motivations. This view has proved to be inadequate because the fact that the nerve cell is not inert has become increasingly evident; the nerve cell does not have to be excited from the outside in order to discharge. The cells of the brain are spontaneously active even during deep sleep. It is not necessary to postulate an extrinsic stimulus or drive to activate them.

In his outstanding book The Organization of Behavior (1949), Hebb did not use the term “drive.” He believed that the main problem of motivational psychology was to account for the direction of behavior and that this could be done in terms of his physiological theories. He changed his opinion, however, when it became clear that there exists an anatomical and physiological basis for a nonspecific drive (1955). The evidence for neurogenic drive rests upon several lines of investigation, particularly upon work in the field of electroencephalography, as well as studies of the reticular activating system.

Brain waves and levels of activation. Donald B. Lindsley (1957) distinguished different levels of activation, or arousal, in terms of brain wave characteristics. When the subject is calm his brain waves reveal a smooth, rhythmic pattern of about ten oscillations per second, known as the alpha rhythm. When the subject is excited, as by the bang of a gun or by pain or anxiety, the alpha rhythm is inhibited and instead there are fast waves of low amplitude. This change of rhythm is known as the activation pattern.

Different levels of activation are revealed in behavior and in awareness, as well as in the pattern of brain waves. Figure 1 represents some of these levels of activation [seeNervous system].

The reticular activating system. The reticular activating system is a network of fibers and synapses located at the levels of the medulla, hypothalamus, and subthalamus. It consists of two main parts: (1) the brain stem reticular formation, a network with many synapses and neural subsystems; and (2) a system of fibers that project diffusely from the thalamic nuclei to many regions of the cerebral cortex.

It is known that every sensory stimulation has two kinds of effects upon the cerebral cortex: impulses are discharged through thalamic nuclei directly to the cortical areas where they provide sensory information; and impulses are sent through collaterals into the reticular activating system and are conducted over diffuse multisynaptic pathways to all parts of the cortex—to both sensory and non-sensory areas—where they have a nonspecific activating effect.

The reticular activating system is not limited to one-way conduction—from sensory nerves to cortex. The system is excited by cerebral action, which in turn produces motor effects over efferent pathways. It is likely that when one anticipates misfortune, as in anxiety, the cerebral cortex excites the reticulum. The motor effects are general, such as increasing muscle tonus in widespread regions.

The feedback from all reactions has a dual effect. When, for example, the organism maintains a set of attention or when effort is expended, as in driving an automobile against a blinding light, there is a sensory feedback from the proprioceptors. This feedback conveys sensory information and also has a nonspecific activating influence.

Cue function and arousal function. Hebb distinguished between cue function and arousal, or vigilance, function. Cue function exists when sensory stimulation transmits information directly and efficiently to the cerebral cortex over the great sensory projection systems: from sensory nerve to sensory tract, thence to the corresponding sensory nucleus of the thalamus, and thence directly to one of the projection areas of the cortex. Arousal function is different. Collaterals from sensory nerves feed excitations into the reticular activating system. These excitations trickle through a tangled thicket of fibers and synapses. There is mixing of messages, and the scrambled messages are delivered indiscriminately to wide areas of the cortex. In fact, the excitations are no longer messages. Instead of conveying information they serve to tone up the cortex with supporting excitations that are necessary if the messages are to have their effect. Without the arousal system, the sensory impulses over the direct and quick routes would reach the sensory cortex and go no further; the rest of the cortex would be unaffected; learned associations would be unavailable for behavior [seeAttention].

The arousal function implies a nonspecific, neurogenic drive. This drive is an energizer, not a guide; an activator, not a steering mechanism. Hebb (1955) claimed that direction and regulation are dependent upon cue function, but cue function is useless and impotent apart from arousal, or drive.

This view is important because it points to a source of motivation underlying observant, manipulative, exploratory, playful, and other forms of behavior. One does not have to look outside the nervous system for sources of physiological drive.

Affective arousals

A complete theory of physiological drives must take account of affective arousals associated with stimulation, frustration, play, rewards bestowed, and punishments inflicted.

Traditionally, the affective processes have been regarded as conscious experiences of pleasantness and unpleasantness that are present in simple feelings, emotions, moods, and sentiments. The affective processes vary in sign (positive or negative), intensity, and temporal course. Sign and intensity can be represented on a bipolar continuum as in Figure 2.

The hedonic continuum extends from the extreme of negative affectivity (distress) to the extreme of positive affectivity (delight), with indifferent processes at the midpoint. Different intensities of affective arousal are represented by arbitrary units marked off upon the continuum. Arrows indicate two important directions of hedonic change: toward the positive pole and toward the negative pole.

Young and others have shown that affective processes can be studied objectively and quantitatively with need-free rats. As a single example, consider a study by Young and Madsen (1963). Using a brief-exposure preference technique, they obtained data for plotting a curve that showed the hedonic equivalence of simple solutions of sucrose and saccharin. Using compound solutions, they plotted isohedonic contour lines on a surface defined by the concentrations of sucrose and saccharin. The contour lines showed the hedonic equivalence of simple sucrose standards and compound sucrosesaccharin solutions.

The affective arousals are in the nervous system. They energize behavioral patterns that lead to approach and withdrawal and that influence choice and the development of preferences. The physiology of affective processes is under extensive investigation.

James Olds (1955) demonstrated that if bipolar needle electrodes are implanted within the limbic system of a rat’s brain, electrical stimulation of subcortical points may be either rewarding or punishing. When stimulated in the septal area, the rats acted as if they liked the internal excitation. For example, if a hungry rat was stimulated in the septal area while he approached food, he would stop at the place where internal stimulation occurred rather than proceed to the food. Again, an apparatus was arranged so that pressing a bar stimulated points within the septal area. Rats repeatedly pressed the bar, but bar pressing ceased promptly when the circuit was broken and there was no longer septal stimulation. The stimulation of other points was punishing. For example, if the needle electrode was implanted in the medial lemniscus, a rat acted as if stimulation hurt him. In the absence of internal stimulation a rat pressed the bar in about 2 to 10 per cent of the total time during a two-hour test, but with self-stimulation in the medial lemniscus the bar-pressing score dropped to zero. The rat avoided the lever. Self-stimulation at other subcortical points was neutral—neither rewarding nor punishing.

Similar results have been obtained by other workers and with cats, monkeys, and other subjects. There can be no doubt that affective arousals have an objective existence within subcortical centers [seeNervous system, article onbrain stimulation].

Physiological drives and reinforcement

Major research problems center on the relation between physiological drives and learning. It should be clear from this discussion that a psychologist must consider the nature of drive when exploring problems of learning and development.

From the point of view of stimulation theory the major emphasis has been upon conditioning. Thus, John F. Dashiell hypothesized that when an external stimulus frequently occurs with a drive stimulus, the external stimulus becomes a substitute for the drive stimulus and tends to elicit the same responses. Again, Edward E. Anderson argued that in the early stages of learning, behavior is controlled by internal drives, but as learning progresses there is increasing environmental control of behavior—a transition that he called the externalization of drive.

From the point of view of homeostatic need the emphasis has been upon need and drive reduction. Thus, Clark L. Hull argued that responses are reinforced when they lead to drive reduction and the meeting of a need; and secondary drive is acquired through association with primary drive reduction.

The neurogenic theory of drive implies that drive reduction is not necessary to learning. And the affective arousal theory implies that behavioral patterns are organized in a way that leads to hedonic change toward the positive pole of the bipolar continuum (Figure 2 ), independently of drive reduction. A hedonic principle is presupposed by Edward L. Thorndike’s well-known law of effect.

Paul Thomas Young

[See alsoMotivation. Other relevant material may be found inEmotion; Learning; and in the biographies ofCannon; Thorndike; Woodworth.]

BIBLIOGRAPHY

The study of physiological drives can be pursued in the texts by Berlyne 1960; Bindra 1959; Brown 1961; Cofer & Appley 1964; Hall 1961; and Young 1961.

Beach, Frank A. 1956 Characteristics of Masculine “Sex Drive.” Volume 4, pages 1–32 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

Berlyne, D. E. 1960 Conflict, Arousal, and Curiosity. New York: McGraw-Hill.

Bindra, Dalbir 1959 Motivation: A Systematic Reinterpretation. New York: Ronald Press.

Bolles, Robert C. 1958 The Usefulness of the Drive Concept. Volume 6, pages 1–33 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

Brown, Judson S. 1961 The Motivation of Behavior. New York: McGraw-Hill.

Cofer, Charles N.; and Appley, Mortimer H. 1964 Motivation: Theory and Research. New York: Wiley.

Duffy, Elizabeth 1962 Activation and Behavior. New York: Wiley.

Estes, William K. 1958 Stimulus–Response Theory of Drive. Volume 6, pages 35–69 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

Hall, John F. 1961 Psychology of Motivation. New York: Lippincott.

Hebb, Donald O. 1949 The Organization of Behavior: A Neuropsychological Theory. New York: Wiley.

Hebb, Donald O. 1955 Drives and the C.N.S. (Conceptual Nervous System). Psychological Review 62: 243–254.

Hull, Clark L. 1943 Principles of Behavior: An Intro→ duction to Behavior Theory. New York: Appleton.

Lindsley, Donald B. 1957 Psychophysiology and Motivation. Volume 5, pages 44–105 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

Nissen, Henry W. 1954 The Nature of the Drive as Innate Determinant of Behavioral Organization. Volume 2, pages 281–321 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

O’kelly, Lawrence I. 1963 The Psychophysiology of Motivation. Annual Review of Psychology 14:57–92.

Olds, James 1955 Physiological Mechanisms of Reward. Volume 3, pages 73–139 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

Richter, Curt P. 1943 Total Self Regulatory Functions in Animal and Human Beings. Harvey Society, New York, Harvey Lectures 38:63–103.

White, Robert W. 1959 Motivation Reconsidered: The Concept of Competence. Psychological Review 66: 297–333.

Woodworth, Robert S. 1918 Dynamic Psychology. New York: Columbia Univ. Press.

Woodworth, Robert S. 1958 Dynamics of Behavior. New York: Holt.

Young, Paul T. 1961 Motivation and Emotions: A Survey of the Determinants of Human and Animal Activity. New York: Wiley.

Young, Paul T.; and Madsen, Charles H. Jr. 1963 Individual Isohedons in Sucrose-Sodium Chloride and Sucrose-Saccharin Gustatory Areas. Journal of Comparative and Physiological Psychology 56:903–909.

II ACQUIRED DRIVES

As used by contemporary behavioral scientists, the term “acquired drive” (synonyms: secondary motive, psychogenic drive or need, acquirable or learnable drive, and sociogenic need) refers to a motive, need, or source of motivation (rarely defined) that is a product of learning. In principle, animals as well as man can acquire drives, but man’s opportunities for such learning during the process of socialization are held to be far more numerous, and the complexity and diversity of his activities are thought more urgently to demand an acquired-drive interpretation.

Typically, some form of learned drive is invoked in accounting for such behavior as working for money; seeking power, affection, status, or security; and striving for artistic creativity or other “higher” goals. Behavioral phenomena involving the motivational consequences of incentives and the acquisition by neutral objects of rewarding power are closely linked with those subsumed under the heading of acquired drives.

Precise, carefully worded definitions of the phrase “acquired drive” are not often encountered in the writings of behavior scientists, nor is it customary to find clear descriptions of exactly what is being learned or of how behavior is affected “motivationally” thereby. This looseness of conception and expression permeates writing in this field, and the multiplicity of different views resulting therefrom suggest that acquired-drive concepts are still in primitive stages of development.

Historical notes

Philosophical, literary, and religious writings from the earliest times contain references to the desires, strivings, wishes, and motives that have been said to govern man’s behavior. And from the Middle Ages onward, references to the will and to conation became increasingly common in the theories of the famous philosophers. But it was not until the latter part of the nineteenth century that the concept of motivation entered boldly and systematically into science-Oriented psychological concepts of behavior. Many factors exerted an effect at that time. Darwin’s views advanced the growing tendency to regard unlearned predispositions as the most important sources of motivation, a tendency strengthened by William James’s insistence on the multiplicity of man’s instincts and by William McDougall’s emphasis on innate propensities and their correlated emotional qualities. Freudian theory likewise under-scored the importance of unlearned primitive motivational forces and may have been the first to emphasize a nonspecific driving agency, the libido. Students of animal learning, notably Edward L. Thorndike, found the primary drives and rewards of tremendous practical importance in teaching animals to make new responses, and the “law of effect” emerged as the conceptual counterpart of efficient training procedures.

During the first two decades of the twentieth century, Watsonian doctrine was accompanied by a decline of interest in the introspectionistic emphasis on the will as the precursor and cause of action, a shift that was reflected in the rather widespread substitution of the term “reaction” for “action.” Robert S. Woodworth, in 1918, was apparently the first in America to use the specific term “drive.” He distinguished drive, as the energy that moves the organism, from the other mechanisms that direct and control reactions, a distinction that has been widely adopted. Moreover, his notion that habits can be converted into drives may constitute a historically memorable reference to acquired-drive phenomena.

Although O. H. Mowrer’s classic paper on the motivating effects of learned anxieties appeared in 1939 and Henry A. Murray published his list of psychogenic needs in 1938 (Explorations … 1938), Neal E. Miller was apparently the first to make use of the term “acquired drives,” in the title of a paper published in 1941. Moreover, the chapter on acquired drives in Miller and Dollard’s Social Learning and Imitation (1941) looms large as the first general theoretical treatment of such drives. The recent emphasis upon secondary drives reflects, in part, the intermingling of Freudian and stimulus— response doctrines, a growing confidence in the idea that intervening variables could be given precise operational meanings, and an increasing tendency to extrapolate to humans theories based on animal behavior. Whereas experimental studies of learned drives have burgeoned during the past decade, systematic theoretical analyses have not. Such cogitations will have to wait upon further developments in the broad field of motivation in general; there are strong signs that cherished conceptions in the latter area are being seriously challenged. Prominent theories of motivation have been expertly summarized by Madsen (1959) and the University of Nebraska Symposia on Motivation, published yearly since 1953, provide an excellent over-all view of the thinking of American psychologists on the general topic of motivation.

Current trends and basic problems

The present-day tendency to appeal to a concept of acquired drives can be ascribed to a variety of factors. Some champions of the acquired-drive view justify their stand on the ground that learned human motives are manifestly visible “on the face of behavior.” This attitude may mirror the fact that the language to which most of us have been exposed during the early years of life is not the language of science, particularly behavioral science, but that of the arts, literature, and religion. This nontechnical lexical heritage, which we learn first and best, contains a wide variety of such “motivational” synonyms as needs, wishes, impulses, desires, motives, aspirations, and hopes. Having matured within this linguistic environment, the student of behavior is almost certain to believe that these well-worn words, like other words learned at the parental knee, denote existential realities. He is also quite likely to feel that each of these “entities” is an important determinant of behavior and that his task as a scientist is simply to find ways of identifying and quantifying them.

A second reason for the widespread acceptance of the acquired-drive notion is the general conviction that biological drives, although capable of explaining certain instances of animal behavior, are inapplicable to human activities. Homeostatic regulatory mechanisms and biological deficiency states are deemed impotent in accounting for the alleged fact that man is motivated to work for praise, power, and recognition. It is considered self-evident, therefore, that man is driven by nobler, more intellective, more spiritual tendencies. Perhaps this is why acquired-drive concepts are never invoked to explain the persistence of morally or socially undesirable behavior. The activities of theologians, musicians, and scientists are held to reveal the power of sociogenic motives but the actions of dope peddlers, prostitutes, or garbage collectors are not.

A third reason for stressing the role of learning in motivation is that individuals are seen to vary among themselves to a surprising degree. This variation, both within a single society and from one society or culture to another, exceeds expectations based solely on genetic mechanisms. Attention is drawn, therefore, to what the individual learns during the course of his development when multitudes of objects and varieties of behavior are allegedly acquiring value. It is a sensible next step, some maintain, to assume that as values are being acquired, needs or drives for objects or for courses of action are also being learned.

Reappraisal

Although these arguments carry some conviction, there is a growing body of opinion favoring the conclusion that learned-drive constructs may not be essential to adequate theories of human behavior. For example, Estes (1958), Brown (1961), and others have seriously considered the possibility that motivational constructs, at least those of the traditional biogenic variety, may be superfluous and that adequate interpretations of alleged motivational phenomena may in some cases be based solely upon associative learning concepts. These views have not been extended, as yet, to secondary-drive manifestations, but there is no reason, in principle, why this could not be done.

The central theme, of course, is simply that complex human behavior is learned and that its acquisition is governed by known learning processes. If power-seeking behavior, for instance, were under scrutiny, one would aver that reinforcement (as yet largely unspecifiable) is responsible for the acquisition and maintenance of the actions. Instances in which motivational processes seemed to be operative would be termed illusory, the illusion being laid to the fact that some of the variables of which behavior is a function have been erroneously dubbed “motivational” by uncritical precursors. The known capacity of such variables to affect the organism would be put down to altered stimulation, a stratagem that reduces all so-called motivational variables to stimulus variables. According to this view, in a word, man learns to react but not to be motivated. Neither the artist, nor the novelist, nor the office secretary need be regarded as having, respectively, drives to paint, write, and type. Each has learned to perform certain acts because these have been repeatedly reinforced by the complex societal machinery in which they are embedded.

Actually, a theorist would not be required to abandon the concept of motivation altogether. He might maintain, for example, that a theory should include primary but not secondary sources of drive. Thus, whatever motivational process the theory demands could be provided by primary sources of drive, such as mild hunger, thirst, or sexual needs. These and other biogenic sources of drive, operating in conjunction with learned reactions, could easily give one the impression that persisting behavior reflects a learned drive for a goal object of some sort.

Those who accept, as a working hypothesis, the view that some kind of learned-drive concept is desirable or necessary must wrestle with many subsidiary problems. Chief among these is the issue of whether a learned drive, or for that matter any drive, should be conceived as having both energizing (activating) and behavior-directing functions. Hull (1943), Spence (1956), and Duffy (1951) may be seen as representing those who have, in part or in whole, regarded drive as a unitary, non-specific, energizing agency and have attributed the directionality or specificity of behavior to associative tendencies or habit strengths. The fact that such variables as food deprivation seem to affect the direction of behavior is handled by assuming that such variables influence not only drive level but also the intensity, quality, or number of deprivation-generated stimuli.

Many other writers, of course (Explorations … 1938; Young 1961), are insistent that drives (sometimes motives) must be directing, response-selecting agents, as well as activators. Young states repeatedly that motivation “is the process of arousing action, sustaining the activity in progress, and regulating the pattern of activity” (1961, pp. 23–24). Moreover, he adds that he would broadly define the study of motivation as “a search for the determinants (all determinants) of human and animal activity” (ibid., p. 24). To adopt such a view, of course, is to rob the term “motivation” of all unique characteristics. As a search for all the determinants of activity, motivation becomes co-extensive not only with all of psychology, but with all other sciences, natural or social, that contribute to the understanding of behavior.

Closely allied with the question of whether a drive or motive can guide or steer behavior is the problem of whether the drive itself can properly be said to have direction. Here again those who embrace such broad definitions as the foregoing tend also to say that one has drives for particular goal objects or conditions. This view may well be a carry-over from purposive conceptions of behavior and appears to be plagued with many of the ancillary difficulties that teleological notions must surmount. For example, how can one decide, unequivocally, that one particular object or bit of behavior, rather than something else, is the goal? Consider the man who works hard in his office, is praised by his boss, gets a raise in salary, buys a new car, gets a date because of the car, and consequently is able to frustrate a rival suitor. In this case, the praise, the raise, the car, the date, or the satisfaction of thwarting the rival might each be described as a goal. But it would make little sense to say that the man had acquired a drive for each of these goals or a drive for one to the exclusion of all others. Actually, advocates of the position that one may have a drive for a specific goal object have never defended this concept on systematic or theoretical grounds. The only support has been of the “we know this is true” variety. Nor has the attribute of “having a drive for something” ever been assigned specific action-determining properties within a formal behavior system.

Drive as dissatisfaction with status quo. Interestingly enough, although fear is widely regarded as a good example of an acquired drive, one never says that fear is a drive for anything specific. Such an assertion would make sense only if one were to argue that the drive of fear is a drive for a non-fearful status. Since many different actions may be equally effective in getting an organism away from fear-arousing stimuli, the “goals” of the fear drive, if this manner of speaking is permissible, are incredibly numerous. But in the same way, of course, one may say that the drive for food is a drive to get away from hunger. Apparently all so-called drives or sources of drive share the property of being states or conditions from which the organism would prefer to escape. Even the emotion of hope, regarded by some as a “positive” drive, may be seen as indicating a lack of the thing hoped for and, hence, as essentially unpleasant. Hope, to be sure, may involve pleasant anticipations, but since it is always characteristic of the pregoal attainment periods, it is undesirable relative to the actual goal. Perhaps, therefore, the only meaningful sense in which a drive may be said to be a drive for something is in the sense in which it must be a drive to be anything but what it is at the time it is functioning as a drive. This holds for the drive to be an artist, to convert the heathen, or whatever. All involve dissatisfaction with the status quo. Every assertion to the effect that behavior is activated by positive, future goals can thus be transformed into the counterproposition that the behavior is driven by a contemporary state of unrest or imbalance. Such a translation is, it will be seen, consistent with the view that empirical variables can be identified as motivational provided (1) they serve as relatively nonspecific energizers, (2) their elimination following a response is reinforcing, and (3) their appearance following a reaction is punishing. Conditions that are inherently “positive” would not meet the second and third of these rather widely accepted criteria for identifying motivational variables.

The incentive-motivation construct. An interesting example of what appears, at first sight, to be an acquired drive for a specific goal is provided by the Hull-Spence construct of incentive-motivation. Suppose that one has been fed at a given region in space and is now situated at a point from which a food reward is invisible. At such a time the visual stimuli provided by food can serve no incentive function and cannot elevate drive level directly. Hidden rewards cannot affect an organism’s prereward behavior save through the agency of a stimulus-evoked anticipatory response. According to Spence, when a subject is rewarded, a consummatory goal response becomes classically conditioned to the cues provided by the food and to the surrounding environmental stimuli. Similar stimuli at a distance evoke fractional parts of the goal response, and these components of the total goal reaction are held to contribute in some measure to total drive level. Thus, even prior to reaching the reward, the subject reacts anticipatorily and appropriately with respect to it, and these reactions are said to increase drive. Inasmuch as these components of the total goal response are uniquely relevant to the particular reward experienced on previous trials, it might be tempting to speak of an acquired drive for that rewarding object. Nonetheless, whereas the anticipatory responses of salivating, chewing, and the like are appropriate to food, the increment in drive level, or incentive-motivation, that they are postulated to generate is not. Within the Hull-Spence theory, incentive-motivation, like drive, is a multiplier of habit strengths and contains no integral label directing it toward or away from any particular goal object [seeHull].

What is learned in acquired drives. Little can be said that is definitive in reply to the general question, “What does one learn when one learns to be motivated?” Typically, phasic or rhythmical skeletal movements have rarely been nominated for positions of central importance in secondary-drive theory. Such reactions are not specifically excluded; the Miller–Dollard view suggests that any learned reaction capable of producing strong internal stimuli qualifies as an acquired drive. Emotional reactions are most frequently cast in the role of drives, with the accent placed on learned expectations of pleasant events (hopes) and anticipations of noxious events (fears or anxieties). Emotional systems are favored because they are relatively diffuse (as is also the case with such primary motivating conditions as hunger), they can be conditioned readily and, if the unconditioned stimulus is strong, resist extinction remarkably well. Verbal reactions, particularly those involving self-directed, “try hard” instructions have only recently been suggested for consideration as learned responses potentially capable of functioning as sources of drive. Provided these responses can be woven securely into well-established learning theories, they may serve a valuable function as contributors to drive.

Inadequacies of theoretical formulations. We terminate this section by noting again that acquired-drive theorists have been gravely remiss in formulating specific theoretical presuppositions and details. Few have wrestled with the question of whether it is profitable to postulate the existence of more than one acquired drive and, should this question be answered in the affirmative, in what ways the drives resemble or differ from one another and from primary sources of drive. Similarly, little attention has been paid to the puzzles of whether drives should be treated as having directing as well as activating functions, whether whatever is learned in the process of acquiring drives is similar to other learned behaviors, how such new learnings are brought about, and how an acquired drive functions when it is alleged to be operating “motivationally.” Some of the solutions proposed as answers to these queries are noted in the following review of research and theory in the field of conditioned emotionality.

Conditioned emotional responses

This discussion begins with, and concentrates on, an examination of the acquired drive of fear (sometimes termed “anxiety”) because this exemplifies the most tightly reasoned theory and the most convincing experimental buttressing in the acquired-drive literature.

Whereas Freud clearly saw that a learned anxiety might have motivating properties and that its reduction would be rewarding, Mowrer (1939) crystallized these notions by translating them into the newly developing stimulus-response-reinforcement language of the 1930s. Linking Freud’s conception with Pavlovian conditioning principles, Mowrer proposed, in brief, that the repeated paired presentation of a neutral and a noxious stimulus would result in the conditioning of anxiety to the neutral cue. After a few such trials, presentations of the neutral stimulus alone should evoke the learned emotional state. Moreover, this state ought to serve as a drive, because its presence should exert a dynamogenic effect upon other responses and its diminution, following a response, should be reinforcing.

Experimental data from a variety of sources indicate that conditioned fear exhibits these motivation-like properties. The conclusion, therefore, seems firmly established that reactions leading to the cessation of fear-arousing cues will be strengthened. Fear has also been shown to have an energizing or activating effect under rather specialized circumstances; the augmentation of startle reactions to auditory stimuli provide the clearest example. Ample support for the view that fear also manifests dramatic inhibiting properties comes from studies showing that lever-pressing reactions in the rat cease almost entirely in the presence of stimuli formerly paired with shock. This response-suppressing function, taken at face value, does not seem to square with the concept of fear as an acquired drive, but one might assume in these instances that the onset of fear has followed and has blocked bar pressing because of a punishing property characteristic of all drive states [seeEmotion; Phobias].

Generalization to human behavior. Extensions of these experimentally demonstrated principles to human behavior have been common. Usually the accent has been placed on the position that anxieties are probably entirely acquired and that anxiety-reducing behavior tends to be perpetuated. Moreover, it has been argued that many human activities that appear to reflect acquired drives for particular goals are actually motivated by anxiety. Thus, for example, behavior suggesting a secondary drive for money has been reinterpreted as reflecting a learned tendency to be anxious in the absence of money. The receipt of money necessarily reduces this “deficiency anxiety,” which, in turn, reinforces money-obtaining actions, such as working. Comparably, the gregarious reactions of both humans and animals have been regarded as reflecting an anxiety-like state produced by physical isolation and reduced by companionship [seeAnxiety].

Perhaps the most successful application of the conditioned fear paradigm has been its use in the interpretation of behavior that repeatedly succeeds in enabling one to avoid an impending traumatic event. The problem to be surmounted here is that each anticipatory avoidance reaction prevents the noxious stimulus from impinging on the subject and, hence, constitutes an extinction trial. Avoidance reactions, however, are sometimes remarkably resistant to extinction, and it is this observation that is explained by saying (Mowrer 1939) that avoidance responses are strengthened by virtue of their own anxiety-reducing function. The conditioned anxiety hypothesis also has furthered our understanding of guilt reactions. Here it is assumed that the emotional reaction becomes conditioned to internal, response-produced cues as well as to external ones. Therefore, when the first elements of a punished response sequence are evoked, the cues generated by these reactions evoke conditioned fear, guilt, or apprehension. Interrupting the chain by doing something else eliminates the guilt and thereby reinforces the competing “virtuous” responses.

Variables contributing to fear. Concerning the variables of which fear is believed to be a function, there appears to be rather general agreement that fear increases with the intensity of the noxious stimulus; with the number of conditioning trials, for a time at least; and perhaps also with lengthened intertrial intervals and with the strength of an appetitive source of drive such as hunger. The principal procedure for eliminating or reducing fear is that of the Pavlovian extinction trial, on which the conditioned stimulus is presented without the unconditioned stimulus. Extinction may be accelerated by massing trials and by structuring the situation to permit competing activities, for example, when one eats in the presence of the conditioned stimulus. Incidentally, the empirical finding that learned fears are extremely resistant to extinction when very noxious stimuli have been used has stilled the earlier criticism that acquired anxieties are too transitory to provide a stable base for persisting human reactions. Indeed, it has been suggested by Solomon and Wynne (1954) that anxieties acquired under these “traumatic” conditions may never be extinguished completely, because the changes produced by the learning process may be irreversible.

Need for achievement

In recent years an ambitious theoretical and experimental program concerned with the psychogenic drive, “need for achievement,” and other motives from Murray’s list has been carried out by D. C. McClelland, J. W. Atkinson, R. A. Clark, and E. L. Lowell (1953). The conceptions of these investigators are included here inasmuch as their theory gives central staging to an affective arousal model of motivation. Two kinds of affective conditions are described. One, a negative state (anxiety), differs in no discernible way from the conditioned fear concepts of motivation discussed above. The other, a positive state (appetite), is essentially an anticipatory reaction to the coming of a pleasant stimulus and is the consequence of the pairing of neutral cues with pleasant ones. A motive, for these investigators, is the arousal of either a positive or negative affect by the presentation of a conditioned stimulus. Thus all motives are necessarily learned, but it is not clear whether the primary affective reactions that serve as the basis for the conditioning of motives are, or are not, motivating. Part of the difficulty here arises from a failure to spell out precisely the effects of motives on behavior in general. Apparently, a motive (the affective expectancy) operates as a selective facilitator of actions appropriate to the motive. These motives thus seem to function as though they provided cues appropriate to the criterion reactions rather than as general activators. This has led to the suggestion that the term motivation may be inappropriate to this work, Although obviously so long as the study of motivation is as broadly defined as it often is, hardly any usage can be pegged as inappropriate [seeAchievement motivation; Field theory].

This review has presented only the barest outline of the acquired-drive problem in all its complexity. Contemporary conceptions stress the view that an acquired drive is, in essence, a learned response, often an operationally definable emotion, such as fear, hope, or anxiety, capable of affecting other responses “motivationally.” Because the functions most commonly described as “motivational” are those of energization, reinforcement, and punishment, a learned response seems to qualify as a motivational variable and, hence, as a secondary source of drive, provided it displays these functions with respect to other responses. Contemporary writers, however, also seriously entertain the notion that acquired-drive concepts are not required even when complex human behavior is being interpreted. For these theorists, the principles of associative learning theory are adequate to explain phenomena that, to others, are patently motivational.

Judson S. Brown

[Directly related are the entriesLearning, article onreinforcement; Motivation, article onhuman motivation. Other relevant material may be found inLearning theory; Motivation; Personality: contemporary viewpoints, article ona unique and open system; Stimulation drives; and the biographies ofThorndikeandWoodworth.]

BIBLIOGRAPHY

Brown, Judson S. 1961 The Motivation of Behavior. New York: McGraw-Hill.

Duffy, Elizabeth 1951 The Concept of Energy Mobilization. Psychological Review 58:30–40.

Estes, William K. 1958 Stimulus–Response Theory of Drive. Volume 6, pages 35–69 in Marshall R. Jones (editor), Nebraska Symposium on Motivation. Lincoln: Univ. of Nebraska Press.

Explorations in Personality: A Clinical and Experimental Study of Fifty Men of College Age, by Henry A. Murray et al. 1938 London and New York: Oxford Univ. Press.

Hull, Clark L. 1943 Principles of Behavior: An Introduction to Behavior Theory. New York: Appleton.

McClelland, David C. et al. 1953 The Achievement Motive. New York: Appleton.

Madsen, K. B. 1959 Theories of Motivation. Copenhagen: Munksgaard.

Miller, Neal E. 1941 An Experimental Investigation of Acquired Drives. Psychological Bulletin 38:534–535.

Miller, Neal E.; and Dollard, John 1941 Social Learning and Imitation. New Haven: Yale Univ. Press.

Mowrer, Orval H. 1939 A Stimulus–Response Analysis of Anxiety and Its Role as a Reinforcing Agent. Psychological Review 46:553–565.

Solomon, Richard L.; and Wynne, Lyman S. 1954 Traumatic Avoidance Learning: The Principles of Anxiety Conservation and Partial Irreversibility. Psychological Review 61:353–385.

Spence, Kenneth W. 1956 Behavior Theory and Conditioning. New Haven: Yale Univ. Press.

Young, Paul T. 1961 Motivation and Emotions: A Survey of the Determinants of Human and Animal Activity. New York: Wiley.