by Morton Hunt
While there are major differences in the cultural situations evoking particular emotions, the evidence strongly suggests that the basic emotions are universal and are accompanied by the same movements of facial muscles.25
This does not prove that physical sensations precede the perception of emotion, as James and Lange posited. But more than a dozen experiments by Ekman and by others have shown that when volunteers deliberately assume the facial expression of a particular emotion, the muscular efforts involved create small but measurable changes in pulse rate, respiration rate, and skin conductance, along with equally small but measurable changes in their feelings.26 Ekman considers these results a feedback effect: the deliberately assumed expression brings about bodily changes, which then create the emotional feeling the person has simulated.
The same principle sometimes enables psychotherapists to alter the emotions of patients. By changing facial expression, posture, and body movements, the patient can to some extent replace a despondent or defeated mood with a more positive and cheerful one.27 Again, this supports the James-Lange theory: What we sense in the body determines our feelings. (Make the experiment yourself. Wreathe your features in a great, sunny grin, hold it for some seconds, and see if you don’t feel at least a modicum of the feeling that should go with it.)
For such reasons, the James-Lange theory survives—or at least is part of the contemporary understanding of the emotions. In recent decades, research by cognitive psychologists and by cognitive neuroscientists has yielded a complex, multifaceted explanation of the interaction between the physical symptoms of emotions and the neural processing of those symptoms and of the stimuli responsible. Which comes first, which produces the other? Each one, at times, depending on all sorts of conditions, and often both in a species of feedback. We will spare ourselves the intricacies for now; the net results suggest that both sides in the debate are right and that the neural systems of emotion and cognition are both independent and interdependent.28
In sum, the somatic theory is a valid but imperfect and limited part of the contemporary answer to the question about the sources of the emotions. Now let us go back to look at other theories explored during the last century that have contributed importantly to today’s view of the matter.
ANS and CNS Theory
Walter Cannon, whose experimental work called into question the James-Lange theory, offered his own theories of emotion and motivation; each was influential for many years.
His motivation theory—sometimes irreverently referred to as the spit-and-rumble theory—held that peripheral clues are what motivate a creature: a dry mouth will prompt drinking, a rumbling stomach will lead to eating. These clues, sending messages to the ancient part of the brain, there give rise to the drive to seek water or food.29 Ironically, Cannon was thus saying about motivation much the same thing he attacked in James’s theory of the emotions.
But Cannon’s theory of emotions was quite different. He held that peripheral or visceral conditions were not the cause of the emotions but concomitant effects of other causes. In gathering his evidence against the James-Lange theory, he decorticated some animals (removed their cortex), after which it took very little stimulus to elicit a rage reaction from them.
This led Cannon and a Harvard colleague, Philip Bard, to suggest that rage and other emotions originate in the thalamus, a primitive structure in the core of the brain that receives information from sense organs (except the nose) and relays appropriate messages to the cortex and the ANS. The cortex, according to the Cannon-Bard theory, usually controls and inhibits the thalamus, but when the thalamus sends it certain kinds of information—the sight of an enemy, for instance—the cortex relaxes its control. The thalamus then is able to send its emotional messages in two directions: to the nervous system, which produces the visceral responses of emotion and the appropriate behavior, and simultaneously back to the cortex, where the feeling of emotion is produced. Thus, the experience of emotion and its visceral symptoms are parallel effects of the thalamic messages.30
Of Cannon’s two theories, the spit-and-rumble account of drive, though dominant for some time, was eventually demolished by other experimental evidence. In 1939 two research studies used “sham drinking” to test it. A fistula surgically made in a dog’s esophagus drained off water as the dog drank, so that none reached the stomach. Although its mouth was wet, the dog continued drinking copiously without allaying its thirst. Evidently, nothing as simple as dry mouth caused the thirst drive; it came from other and deeper visceral signals, turned into action by the nervous system.
The Cannon-Bard emotion theory, however, was strongly supported, although modified, by later research showing that the ANS, thalamus, and other primitive areas of the nervous system could generate emotions without any input participation by the viscera. In the late 1920s and the 1930s Walter Hess, a Swiss physiologist, inserted electrodes in the rear area of the hypothalamus (a part of the core of the brain located below the thalamus) of a laboratory animal and delivered a weak electrical stimulus; the animal acted enraged. When Hess sent the same current into the forward area of the hypothalamus, the animal became calm and sleepy. Much later, José Delgado, a Spanish neuroscientist, demonstrated this hypothalamic control of rage with Iberian flair. He implanted an electrode in the forward area of a bull’s hypothalamus and then entered a bullring holding a control box that would send an electrical impulse through the electrode. The bull was released into the ring, saw Delgado, grew enraged, and charged. Delgado, unflinching, pushed the button, and the bull halted and turned away.31
At Yale in the 1950s, Delgado and several colleagues did equally impressive, if less theatrical, research with electrode implantations in rats and cats. By sending a weak current into a cat’s or rat’s amygdala—a part of the “limbic system” or ancient mammalian brain, a series of structures located between the thalamus and the cortex—they produced fear behavior. Later, Delgado and others did so with human patients during brain surgery. When one patient was receiving the current, he said he felt as if he had just been missed by a car, another as if “something horrible was about to happen” to her. The feelings ceased as soon as the current was turned off.32
A completely different kind of evidence supporting the limbic-system theory of the emotions was produced in the 1970s by J. E. Steiner, a developmental psychologist. He took pictures of newborn infants to whom, before their first feeding by breast or bottle, he gave water flavored sweet, sour, or bitter. The sweet water caused the babies to lick their lips, the sour water to purse them and wrinkle their noses, and the bitter water to open their mouths and spit or retch. Steiner then did the same with anencephalic newborns (anencephaly is a tragic anomaly in which the fetus develops no brain tissue above the brain stem; the newborn soon dies); they exhibited exactly the same facial expressions and reactions. Simple emotions and their facial expressions thus appear to be generated by the brain stem, although the responses are modified later, in normal children, by higher nervous centers as the children learn what is acceptable emotional behavior in their society.33
In the 1950s Magda Arnold, a Czech-born psychologist at Loyola University in Chicago (one of the few women to attain eminence in psychology before midcentury), and others proposed “arousal theory,” an integrated explanation of both motivation and emotion that held their origin to be the “reticular formation” (a network of neurons connecting the brain stem to the thalamus) and the limbic system.
Arousal theory, supported by research using electrode stimulation of the brain, holds that incoming stimuli “activate” parts of the reticular formation and limbic system, which alert the cortex and ready the creature for action.34 Sounds or smells, for instance, will awaken a sleeping animal; a baby’s whimper will bring its sleeping mother wide awake and on her feet in an instant. Such stimuli as deprivation of water, food, or air, or an increase in sex hormone levels, were also shown by electroencephalograms (EEGs)—brain recordings—to activate the reticular formation and, through
it, to increase heart rate and overall activity.35 In sum, the theory envisioned the reticular formation as a regulatory device that, on receiving signals by the senses, turns on both physiological activity and emotional responses.
But as Phil Evans, senior lecturer in psychology at North East London Polytechnic, has ruefully said of arousal theory, “Few concepts in psychology have proven so bothersome and yet so superficially attractive.”36 For although it provides a neural explanation of both motivation and emotion, and makes sense of a wide array of data, it is too general. It presents only one dimension of emotion—the degree of arousal— which leaves unexplained the diversity of the emotions. Also, physiological measures of arousal like heart rate and skin conductance often fail to agree with EEG data and observed levels of activity. Finally, studies of sleep have shown that during periods of rapid eye movement (REM), an animal or human is deeply asleep yet has brain waves indicating high arousal of the reticular formation.37
The arousal theory has not been abandoned, but theorists now say that arousal is not the source of the emotions but a concomitant of them. Nor is it a unidimensional condition; there are different types of arousal— behavioral, ANS, and cortical—each with its own characteristics.38
The higher-level cortical influences on motivation and emotion, in fact, have been in the forefront of research for nearly half a century. A single recent case history will document the broad-ranging role of the frontal cortex—the center of cognitive processes—on emotions. “Elliot,” a man in his early thirties, developed severe and incapacitating headaches, due to a large benign tumor behind his eyes. Surgeons removed it but could not help removing some of the surrounding frontal lobe tissue. Elliot recovered physically but lost the capacity to make decisions and, most curiously, had no emotional reactions to the many mistakes he began making in his career and personal life. The eminent neurologist Antonio Damasio examined him and reported, “I never saw a tinge of emotion in my many hours of conversation with him: no sadness, no impatience, no frustration with my incessant and repetitious questioning.” When Elliot was shown disturbing pictures such as severely injured bodies, he said he knew the pictures were disturbing and that before the surgery he would have felt disturbed—but now felt nothing.39
Philosophic and religious traditions have held that our emotions and drives originate in our animal or physical side, but modern cognitive psychology, drawing on data of cases like that of Elliot and many other sources of more specific information, finds that many of our emotions and motivations are influenced by, or even originate in, the mind. Let us see the evidence.
Cognitive Theory
Psychologists, in stressing first the somatic and then the thalamic-limbic sources of motivation, were ignoring an everyday truth taken for granted by the average person: human beings and higher-level animals often exhibit emotions and motivations stemming from mental needs, not physiological ones.
Dog owners are well aware of this. They have seen their pet, turned loose in a new or unfamiliar house, immediately explore and sniff around the territory, driven not by hunger or any other somatic need but by a need to know.
Parents are aware of it. They have seen their small child happily push the buttons and pull the levers of a toy cash register or similar toy by the hour, driven by a need to find out how things work.
Everyone knows that after being housebound for a day or two by a storm or a minor illness, one feels a need to get out, look around, and see other places and faces, and after long hours of routine work, a need to do something refreshing to the spirit.
Hull, on a behaviorist basis, and Freud, on a psychodynamic one, held the basic motivation of creatures to be drive reduction, but in the 1960s, as cognition was again becoming the central concern of psychology, a number of researchers began to consider drive reduction theories seriously incomplete and to conduct experiments showing that more advanced creatures are often motivated by cognitive needs and processes.
We learned earlier of two such experiments. The monkeys that opened a window to watch a toy train and those that undid latches without any reward for doing so were motivated not by a physiological need or arousal of the primitive brain but by a cognitive need, namely, for mental stimulation.
Other experiments conducted in the 1950s and after showed that, contrary to behaviorist theory, rats will learn to behave in ways that are unrewarded—at least not by food, water, or other physical gratifications. In several studies, rats chose a path that led them not to food but into a maze, preferred to take a new path rather than a known one leading to food, learned to take a particular fork of a Y maze or to discriminate white from black for the reward of exploring a checkerboard maze, and learned to press a bar to turn on a light when their cage was dark or to turn it off when their cage was bright.40
Not only were the animals aroused by novelty; they actively sought novel situations in order to arouse themselves. Human beings are especially likely to try to arouse their own minds and feelings. We seek to frighten ourselves by going to horror movies, to stir ourselves up sexually by reading erotic material, to challenge ourselves by playing games against opponents as good as or better than ourselves, and to make our minds work by solving puzzles. One psychologist, Fred Sheffield, persuasively made the case that it is not drive reduction that reinforces human behavior so much as drive induction; we seek not so much the completion of the movie, book, or game as the excitement of watching, reading, or playing.41
Such behavior makes sense in terms of evolutionary theory. As the motivation theorist Robert White suggested in 1959, highly developed animals, in order to survive, must learn to deal effectively with their environment. To be curious about novel situations and to be self-arousing is to increase the chance of learning to deal effectively with the environment, and consequently of surviving and reproducing.42
But we do not like or seek as much arousal as possible; we prefer moderate stimulation and dislike what is unduly stressful, extremely frightening, or chaotic.43 This, too, has survival value: we and other creatures function best at intermediate levels of arousal.44 In one of many experiments attesting to this, volunteers were given up to a hundred seconds to solve each of twenty difficult anagrams for a small cash reward. Their level of motivation was measured by having them rate how attractive they found the goal; those who were moderately motivated solved the most anagrams.45 The principle is familiar to everyone. All those who drive cars, play games requiring physical or mental skill, or work for others know that they do not do their best when bored or sleepy—or when under extreme pressure to do well.
Some of the best evidence that the motivation behind self-arousal and exploratory behavior is the desire to achieve competence and control of the immediate environment comes from Piaget’s and others’ studies of children’s cognitive development through play and schooling. We heard about some of Piaget’s relevant observations earlier, but one more example is apropos here. One day Piaget gave his son Laurent, aged ten months, a piece of bread; Laurent dropped the bread, picked it up, broke off pieces, and let them drop again and again, watching each fall with great interest. The next day, Piaget writes,
he grasps in succession a celluloid swan, a box, and several other small objects, in each case stretching his arm and letting them fall. Sometimes he stretches out his arm vertically, sometimes he holds it obliquely in front of or behind his eyes. When the object falls in a new position (for example on his pillow) he lets it fall two or three times on the same place, as though to study the spatial relation; then he modifies the situation.46
The obvious satisfaction such activities yield comes from finding out how the world works and achieving some degree of control over it. In Robert White’s words:
The child appears to be occupied with the agreeable task of…discovering the effects he can have on the environment and the effects the environment will have on him. To the extent that these results are preserved by learning, they build up an increased competence in dealing with the environment. T
he child’s play can thus be viewed as serious business, though to him it is merely something that is interesting and fun to do.47
This is true not only during childhood; in adulthood, though to a lesser extent, we are impelled to expand our knowledge of, and competence in dealing with, the world we live in.48
But this does not explain the intense motivation of some human beings to seek answers to questions that have no utilitarian value: the age and size of the universe, for instance, or the means by which bees tell each other where to find honey, or the extent to which human personality is genetically determined. As Daniel Berlyne, a gifted motivation theorist, wrote about the motivating force of curiosity:
Few phenomena have been the subject of more protracted discussion than human knowledge. Yet this discussion has usually paid little attention to the motivation underlying the quest for knowledge… Strangely enough, many of the queries that inspire the most persistent searches for answers and the greatest distress when answers are not forthcoming are of no manifest practical value or urgency. One has only to consider some of the ontological inquiries of metaphysicians or the frenzy of crossword enthusiasts to be convinced of this.49
The desire to learn and understand, said Berlyne, could be accounted for in part by psychoanalytic theory, Gestalt psychology, and reinforcement theory, but a fuller explanation lies in the motivation of curiosity. In Berlyne’s view, there is a subtler need behind curiosity than the desire for practical knowledge. Strange or puzzling situations arouse conflict in us, and it is the drive to reduce the conflict that impels us to seek answers.50 What motivated Einstein to develop his general theory of relativity was not its immense practical consequences but what he called a “passion for comprehension”—specifically, a need to understand why his special theory of relativity was at odds with certain principles of Newtonian physics.
