MOTIVATION

forces acting either on or within a person to initiate behaviour. The word is derived from the Latin term motivus (a moving cause), which suggests the activating properties of the processes involved in psychological motivation. Psychologists study motivational forces to help explain observed changes in behaviour that occur in an individual. Thus, for example, the observation that a person is increasingly likely to open the refrigerator door to look for food as the number of hours since the last meal increases can be understood by invoking the concept of motivation. As the above example suggests, motivation is not typically measured directly but rather inferred as the result of behavioral changes in reaction to internal or external stimuli. It is also important to understand that motivation is primarily a performance variable. That is, the effects of changes in motivation are often temporary. An individual, highly motivated to perform a particular task because of a motivational change, may later show little interest for that task as a result of further change in motivation. Motives are often categorized into primary, or basic, motives, which are unlearned and common to both animals and humans; and secondary, or learned, motives, which can differ from animal to animal and person to person. Primary motives are thought to include hunger, thirst, sex, avoidance of pain, and perhaps aggression and fear. Secondary motives typically studied in humans include achievement, power motivation, and numerous other specialized motives. Motives have also sometimes been classified into pushes and pulls. Push motives concern internal changes that have the effect of triggering specific motive states. Pull motives represent external goals that influence one's behaviour toward them. Most motivational situations are in reality a combination of push and pull conditions. For example, hunger, in part, may be signaled by internal changes in blood glucose or fat stores, but motivation to eat is also heavily influenced by what foods are available. Some foods are more desirable than others and exert an influence on our behaviour toward them. Behaviour is, thus, often a complex blend of internal pushes and external pulls. factors within a human being or other animal that arouse and direct goal-oriented behaviour. Psychologists have presented a multitude of often-conflicting theories that purport to explain why individuals act at all, why they select the actions they do, and why some people are more motivated than others and succeed where others of similar talents and abilities fail. Some theorists have sought an internal mechanism that gives rise to action; some have explored external stimuli in the environment; some have studied the basic motivations themselves, attempting to establish which are innate needs and which are learned; and some have tried to determine whether motivation directs behaviour toward a particular goal, or whether it simply energizes behaviour determined by other factors such as habit. Thinkers have long identified needs and desires as major elements in the human personality, but it was not until Charles Darwin's theories were applied to psychological adaptation to the environment that researchers began to attend to the question of motivation. Theorists saw two important relationships between Darwin's ideas and motivation. First, that humans, as part of the animal kingdom, are at least partially governed by instincts for food, water, sex, etc. Second, that behavioral characteristics, such as the capacity for motivation, serve an evolutionary purpose just as physical characteristics do. The psychological community seized on the concept of instinct, and, at about the turn of the century, almost every possible behaviour was called instinctive. There was no way to prove these assertions, however, and they lost favour as experiments began to demonstrate that much behaviour previously considered innate was highly modifiable by learning and experience. In the early 20th century, the Anglo-American psychologist William McDougall believed instincts were the prime motivators of human behaviour and emphasized the power of motivation over perceptions and emotions: one perceives what one's instincts motivate one to perceive, and the appropriate object, once perceived, generates a surge of emotions that incites action. Sigmund Freud also based much of human behaviour on irrational instinctive urges and was most interested in the unconscious nature of these motivations. Freud believed the two basic human motivations are Eros (the life or sexual instinct) and Thanatos (the death instinct). In the early 20th century, the American psychologist Robert S. Woodworth introduced the word drive as a substitute for the controversial term instinct. Drive is the force that energizes the organism into action. The American neurologist Walter B. Cannon coined the term homeostasis to explain what he and others (including Freud) considered the main function of motivationto regulate the body. The body, it was postulated, is activated whenever its internal conditions reach a certain level of imbalance. Nonbiological drives were called learned drives and were thought to gain their motivational power through association with biological drives. Later theorists specified that drive itself is a homeostatically conceived but non-goal-oriented state of energy. Direction of this energy toward reduction of the appropriate tension was attributed to habit learned through reinforcement in previous experiences. The drive theory held sway from the 1920s to the '50s, when neurological experiments produced discoveries of arousal states that were at odds with the belief that tension relief was the essential learning reinforcement. It was discovered that intermediate levels of arousal are pleasurable in and of themselves. Furthermore, there are so-called pleasure centres in the brain which, when stimulated artificially, will cause a rat to work until it drops from fatigue. Also, it was shown that animals (including humans) learn even when the reward consists simply of the exploration of a new environment, watching others, or some other stimulation. Other psychologists studied human needs rather than the mechanisms that powered them. Henry A. Murray published a list of needs that were divided into primary (innate) and secondary (learned). These needs, he believed, make human behaviour goal-oriented. Abraham H. Maslow postulated a hierarchy of motivations, from physiological needs (e.g., hunger and thirst) at the bottom, to needs for safety, belongingness, and love, to the need for esteem and, at the top, the needs for self-actualization and for various cognitive and aesthetic goals. He believed that the baser needs have to be satisfied before the individual can move on to satisfying the higher needs. From a behavioral viewpoint, there can be no motivation without a goal. Generally speaking, the more strongly one needs or desires a goal, the more successful one will be in attaining it, although myriad factors such as individual temperament, upbringing, and self-image may intervene. Behaviour therapists stress the importance of a person's attitude toward his goal and postulate three factors that influence motivation: the degree of ambivalence a person feels about his object of desire, one's ability to visualize one's goal clearly, and one's ability to break the goal down into accomplishable smaller tasks. Cognitive psychologists have found that a motive sensitizes the person in cognitive areas related to the motive. Someone with a high need for achievement tends to recognize achievement-related words quickly when they are briefly flashed on a screen; a poor subject sees or remembers coins as being larger than does a rich subject; a hungry subject perceives food stimuli as larger than other stimuli. Psychologists have also postulated that motivations greatly influence a person's choice of occupation. A high need for achievement, for example, is most likely to be satisfied in a business entrepreneurial occupation where there is clear-cut knowledge of results, a sense of personal responsibility, and the challenge of moderate risk. See also emotion. Additional reading The following works are broad studies in psychology, and they, if not cover, then at least touch upon many aspects of the subject of motivation. Charles N. Cofer, Motivation & Emotion (1972), is a concise discussion of the basic relevant psychological concepts. Good overviews of the major approaches to motivation are presented in Herbert L. Petri, Motivation: Theory, Research, and Applications, 3rd ed. (1991); and David C. McClelland, Human Motivation (1985). Niko Tinbergen, The Study of Instinct (1951, reissued with a new preface by the author, 1989), offers an excellent survey of early research using the ethological approach. Development of the ethological school in the behavioral sciences is exemplified in Konrad Lorenz and Paul Leyhausen, Motivation of Human and Animal Behavior (1973; originally published in German, 1968). Irenus Eibl-Eibesfeldt, Love and Hate; On the Natural History of Basic Behaviour Patterns (1971; originally published in German, 1970), examines the role of instinctive behaviour in human motivation. Charles N. Cofer and M.H. Appley, Motivation: Theory and Research (1964), is a monumental survey, which for years was considered a standard in the field. Another broad survey of developments in the period until the mid-1960s, though not as extensive, is M.D. Vernon, Human Motivation (1969). Clark L. Hull, Principles of Behavior: An Introduction to Behavior Theory (1943, reissued 1966), includes a discussion of the learning approach, excluded from Vernon's book. Robert C. Bolles, Theory of Motivation, 2nd ed. (1975), provides a review of the drive concept and its failure to explain all aspects of motivated behaviour. John Jung, Understanding Human Motivation: A Cognitive Approach (1978), covers also all traditional motivational approaches. Hans Selye, The Physiology and Pathology of Exposure to Stress: A Treatise Based on the Concepts of the General-Adaptation-Syndrome and the Diseases of Adaptation (1950), and The Stress of Life, rev. ed. (1976, reissued 1984), provide a good introduction to the understanding of the concept of stress and the body's reaction to it. John W. Atkinson and David Birch, An Introduction to Motivation, 2nd ed. (1978), examines the expectancy-value model of achievement motivation and the relevant research. Abraham H. Maslow (ed.), New Knowledge in Human Values (1959, reissued 1970), and the two books authored by Maslow, Eupsychian Management: A Journal (1965), and The Farther Reaches of Human Nature (1971), outline his ideas concerning self-actualization. Nathan Brody, Human Motivation: Commentary on Goal-Directed Action (1983), provides an overview of all mainstream scientific theories of motivation beginning with Hull. Edward L. Deci and Richard M. Ryan, Intrinsic Motivation and Self-Determination in Human Behavior (1985), offers a comprehensive look at the literature of motivation from Freud to the latest working theories. Herbert L. Petri