Our motivations arise from the interplay between nature (the bodily "push") and nurture (the "pulls" from our thought processes and culture). Consider four perspectives for viewing motivated behaviors. Instinct theory (now replaced by the evolutionary perspective) focuses on genetically predisposed behaviors. Drive-reduction theory focuses on how our inner pushes and external pulls interact. Arousal theory focuses on finding the right level of stimulation. And Abraham Maslow's hierarchy of needs describes how some of our needs take priority over others.
Early in the twentieth century, as the influence of Charles Darwin’s evolutionary theory grew, it became fashionable to classify all sorts of behaviors as instincts. If people criticized themselves, it was because of their “self-abasement instinct.” If they boasted, it reflected their “self-assertion instinct.” After scanning 500 books, one sociologist compiled a list of 5759 supposed human instincts! Before long, this fad for naming instincts collapsed under its own weight. Rather than explaining human behaviors, the early instinct theorists were simply naming them. It was like”explaining” a bright child’s low grades by labeling the child an “underachiever.” To name a behavior is not to explain it.
To qualify as an instinct, a complex behavior must have a fixed pattern throughout a species and be unlearned (Tinbergen, 1951). Such behaviors are common in other species (Module 26 described salmon returning to their birthplace, and Module 48 will describe imprinting in birds). Human behavior, too, exhibits certain unlearned fixed patterns, including infants’innate reflexes for rooting and sucking.
Although instinct theory failed to explain most human motives, evolutionary psychology’s underlying assumption that genes predispose species-typical behavior remains as strong as ever. We saw this in Module 29’s discussion of animals’ biological predispositions to learn certain behaviors. And we will see this in later discussions of how evolution might influence our phobias, our helping behaviors, and our romantic attractions.
When the original instinct theory of motivation collapsed, it was replaced by drive-reduction theory – the idea that a physiological need creates an aroused state that drives the organism to reduce the need by, say, eating or drinking. With few exceptions, when a physiological need increases, so does a psychological drive – an aroused, motivated state.
The physiological aim of drive reduction is homeostasis – the maintenance of a steady internal state. An example of homeostasis (literally “staying the same”) is the body’s temperature-regulation system, which works like a room thermostat. Both systems operate through feedback loops: Sensors feed room temperature to a control device. If the room temperature cools, the control device switches on the furnace. Likewise, if our body temperature cools, blood vessels constrict to conserve warmth, and we feel driven to put on more clothes or seek a warmer environment (FIGURE 37.1).
Not only are we pushed by our need to reduce drives, we also are pulled by incentives - positive or negative stimuli - that lure or repel us. This is one way our individual learning histories influence our motives. Depending on our learning, the aroma of good food, whether freshly baked pizza or freshly toasted ants, can motivate our behavior. So can the sight of those we find attractive or threatening.
When there is both a need and an incentive, we feel strongly driven. The food-deprived person who smells baking bread feels a strong hunger drive. In the presence of that drive, the baking bread becomes a compelling incentive. For each motive, we can therefore ask, “How is it pushed by our inborn physiological needs and pulled by incentives in the environment?”
We are much more than homeostatic systems, however. Optimal arousal theory holds that some motivated behaviors actually increase arousal. Well-fed animals will leave their shelter to explore and gain information, seemingly in the absence of any need-based drive. Curiosity drives monkeys to monkey around trying to figure out how to unlock a latch that opens nothing or how to open a window that allows them to see outside their room (Butler, 1954). It drives the 9-month-old infant to investigate every accessible corner of the house. It drives you to read this text and it drives the scientists whose work this text discusses. And it drives explorers and adventurers such as Aron Ralston and George Mallory. Asked why he wanted to climb Mount Everest, the New York Times reported that Mallory answered, “Because it is there.” Those who, like Mallory and Ralston, enjoy high arousal are most likely to seek out intense music, novel foods, and risky behaviors (Zuckerman, 1979). They are “sensation-seekers.”
So, human motivation aims not to eliminate arousal but to seek optimum levels of arousal. Having all our biological needs satisfied, we feel driven to experience stimulation and we hunger for information. We are “infovores/’ said neuroscientists Irving Biederman and Edward Vessel (2006), after identifying brain mechanisms that reward us for acquiring information. Lacking stimulation, we feel bored and look for a way to increase arousal to some optimum level. However, with too much stimulation comes stress, and we then look for a way to decrease arousal.
Two early-twentieth-century psychologists studied the relationship of arousal to performance and identified what we now call the Yerkes-Dodson law, suggesting that moderate arousal would lead to optimal performance (Yerkes & Dodson, 1908). When taking an exam, for example, it pays to be moderately aroused – alert but not trembling with nervousness. We have since learned that optimal arousal levels depend the task as welt with more difficult tasks requiring lower arousal for best performance (Hembree, 1988) (FIGURE 37.2).
Some needs take priority over others. At this moment, with your needs for air and water hopefully satisfied, other motives – such as your desire to achieve (discussed in Module 82) – are energizing and directing your behavior. Let your need for water go unsatisfied and your thirst will preoccupy you. Just ask Aron Ralston. Deprived of air, your thirst would disappear.
Abraham Maslow (1970) described these priorities as a hierarchy of needs (FIGURE 37.3). At the base of this pyramid are our physiological needs, such as those for food and water. Only if these needs are met are we prompted to meet our need for safety, and then to satisfy our needs to give and receive love and to enjoy self-esteem. Beyond this, said Maslow (1971), lies the need to actualize one’s full potential. (More on self-esteem and self-actualization in Modules 57 and 59.)
Near the end of his life, Maslow proposed that some people also reach a level of self-transcendence. At the self-actualization level, people seek to realize their own potential.
At the self-transcendence level, people strive for meaning, purpose, and communion that is beyond the self, that is transpersonal (Koltko-Rivera, 2006).
Maslow’s hierarchy is somewhat arbitrary; the order of such needs is not universally fixed. People have starved themselves to make a political statement. Today’s evolutionary psychologists concur with the first four levels of Maslow’s needs pyramid. But they note that gaining and retaining mates, and parenting offspring, are also universal human motives (Kenrick et al., 2010).
Nevertheless, the simple idea that some motives are more compelling than others provides a framework for thinking about motivation. Worldwide life-satisfaction surveys support this basic idea (Oishi et al., 1999; Tay & Diener, 2011). In poorer nations that lack easy access to money and the food and shelter it buys, financial satisfaction more strongly predicts feelings of well-being. In wealthy nations, where most are able to meet basic needs, home-life satisfaction is a better predictor. Self-esteem matters most in individualist nations, whose citizens tend to focus more on personal achievements than on family and community identity. (TABLE 37.1 summarizes the strengths and weaknesses of the different perspectives on motivation.)
In the ensuing modules, we will consider four representative motives, beginning at the physiological level with hunger and working up through sexual motivation and the need to belong. At each level, we shall see how experience interacts with biology.
ASK YOURSELF: Consider your own experiences in relation to Maslow’s hierarchy of needs. Have you ever experienced true hunger or thirst that displaced your concern for other, higher-level needs? 00 you usually feel safe? Loved? Confident? How often do you feel you are able to address what Maslow called your “self-actualization” needs?
TEST YOURSELF: While on a long road trip, you suddenly feel very hungry. You see a diner that looks pretty deserted and creepy, but you are really hungry, so you stop anyway. What motivational perspective would most easily explain this behavior, and why?
