Sections include: emotions and behavior, communicating emotions, disorders of the emotions
Human emotion is an ancient system of preverbal communication that has common roots with the signaling systems employed by other mammalian species living together in social groups. Emotional expression evolved millions of years ago when our primal ancestors first began herding together for safety and the protection of their young. It is a system wired deeply into our heads. From the first moments of life outside the womb, long before we can talk, we employ emotional signals—of joy and despair, fear and disgust—to announce when we are hungry and want to be fed, discomforted, or frightened and in need of protection. And from those first moments we are sensitive to the emotional signaling of others. At once preprogrammed and shaped by experience, the human capacity for emotion is a brain system that has evolved in step with the growing complexity of our social interaction.
In Old English the word emotion was synonymous with a public commotion. Only later, in the nineteenth century, was it adopted as a psychological term meaning “to act emotionally or theatrically.” This expression of the “instinctive affectations of the mind” was distinguished from those behaviors reflective of “knowledge and reason.” Charles Darwin, the father of evolutionary theory, was very interested in emotion and was one of the first to recognize its importance as a link to understanding the common roots of behavior among animal species. In his popular book The Expression of the Emotions in Man and Animals, which was published in 1872 and became a scandal in Victorian England, Darwin provided lavish illustration that the emotions are the cornerstone of a stable social order. He established that human emotion is coded in facial expressions and is similar to the nonverbal signaling employed by other social animals, particularly the primates. Thus the facial expressions of anger and fear, disgust and surprise, joy and sadness—those emotions listed by the early philosophers as the primary passions—transcend variations in culture and language as a common means of human communication. The recognition and expression of these primary emotions is, for each of us, as innate and universal as the ability to identify the primary colors of red, yellow, and blue.
Emotions and Behavior
Our emotions are instruments of survival, adaptive behaviors that seek the best fit with prevailing environmental circumstances in the continuous service of preserving life and species. Thus in infancy crying entreats the parent to return, while in the adult, grief and sadness are designed to provoke sympathy and support. In both instances the goal of the emotional behavior is to solicit aid and ensure safety in the face of potential adversity. While in infancy the primary emotions dominate, as we mature into adulthood emotion ecomes increasingly entwined with thinking and memory. The events remembered with particular clarity (moments that give meaning) are those about which we have strong feeling. Thus emotional expression becomes selective and idiosyncratic, and secondary emotions such as pride, shame, and guilt emerge as increasingly important in guiding our behavior. We are, however, herd animals. Our success as a species lies not only in our intelligence but also in our ability to work together in social groups. Thus social circumstance remains the most powerful regulator of emotion throughout life, with situations that promote intimacy, attachment, and security evoking in us expressions of emotional pleasure and happiness, while loss and threat engender the opposite.
Modern neuroscience has taught us that emotion (analogous to other complex behaviors, such as speech, vision, and hearing) originates from the coordinated and balanced activity of many brain centers. For emotion, these centers are located principally in the limbic system, or the old mammalian brain. Of special importance are the almond-shaped amygdalae, one in each temporal horn, which act as the fear centers of the brain and the sentinels of emotional awareness. Working in close harmony with the amygdalae are the centrally located thalami, which serve together as the brain’s telephone exchange, integrating the information coming from the senses and the body organs. New information is first coded in the two hippocampi (where short-term memory is processed) that wrap around the thalami and is then conveyed to the frontal lobes, where the memories of important events are placed in longterm storage for later retrieval and use in future planning. It is also via the circuits of the amygdala complex that the limbic system is wired into the muscles of the face (the vehicles through which we express our emotions to each other) and also to the tiny hypothalamus, at the base of the brain, which helps orchestrate the housekeeping functions of the body. It is because of this intimate linkage that during periods of turmoil, when our emotional balance is temporarily disturbed, the familiar daily rhythms of eating, sleeping, and sexual behavior are disrupted.
An important task of the emotional brain is to continuously integrate the environmental and bodily information gathered from our senses. An awareness of something interesting, novel, or threatening triggers a subjectively heightened state that we describe as feeling. (Actually, psychiatrists call this physiological arousal of the brain’s emotional circuitry affective arousal—from the Latin affectus, meaning “completed action”—and it is the awareness or perception of the arousal that should more accurately be described as feeling.) Most of us are remarkably inept when it comes to characterizing these states of inner feeling. Our verbal descriptions are colorful but imprecise, which perhaps is something to be expected, given that human beings had feelings long before the invention of language.
Communicating Emotions
The words we use to communicate feelings are often descriptions of physical sensations. We speak of the thrill of surprise, the tingling sensation that goes down the back of the neck when something extraordinary happens; pangs of sadness and of hunger; twinges of guilt when an obligation is suddenly remembered, similar to a twinge of pain. In describing the throb of passion, we are comparing the experience with a wildly beating heart. We speak of the gnawing of grief, hankerings, sinkings, chills, qualms, and so on. Our language suggests that feelings are tied closely to an awareness of the body’s changing physiology. But the recognition of physiological “feeling” alone rarely has meaning. Personal interpretation is required, and that is where memory comes in. We string our memories and feelings together as personal stories, as emotional tales, that catalogue the significant moments that make each of us a unique person; these are the stories retold when we describe ourselves to others. Brought together as emotional experience, memory and feeling sustain individual identity, building for each of us unique strengths and unique vulnerabilities.
Individuals vary in the degree to which they experience and express emotion. These variations in the emotional tone are highly heritable and are called temperament, which means, roughly, an individual’s “habit of mind.” Thus some of us are born shy and some bold. As we grow, it is this temperamental predisposition that shapes our approach to others and to experience, helping mold, in turn, the way we are perceived. The shy, introverted individual for whom social interaction is a struggle, for example, and whose natural habit is to withdraw will find the world a difficult and sometimes frightening place. Such “introverts” become conscientious and meticulous workers—civil servants, accountants, diligent teachers, and managers of detail (who are the backbone of human social organization). On the other hand, the bold and impulsive “extrovert” engages the world at a run. Optimism and energy abound. Nothing is too much or too difficult. These are the versatile entrepreneurs who apply themselves successfully to business, to politics, and to adventurous pursuit.
In thinking about emotional behavior, it is important to distinguish among temperament, emotion, and mood. Temperament describes the habitual way in which an individual relates to the world; emotions, on the other hand, are mercurial. In everyday speech the words mood and emotion are often used interchangeably, but strictly speaking, mood is the consistent extension of emotion in time. An emotion is usually transient and responsive to the thoughts, activities, and social situations of the day. Moods, in contrast, may last for hours, days, or even months in the case of some illnesses. Thus the emotional state of grief, when extended in time, is called sadness; if it persists, unrelenting, for a period of weeks, the mood state is referred to as depression, or a disorder of “affect.” Although we speak of affection—meaning fondness or love—affect is not a word we use now in everyday speech. It does appear, however, in the professional vocabulary of psychiatrists and behavioral scientists, where it provides the generic name for a family of illnesses (known as the affective disorders) in which a disturbance of emotional communication and mood regulation predominates. Depression, or melancholia, characterized by recurrent periods of sorrow, self-criticism, and social withdrawal, and its close cousin, mania, where euphoric irritability, overconfidence, creativity, and high energy predominate, are the principal members of this family of brain disorders.
Disorders of the Emotions
Eleven to 15 million people in the United States are afflicted with affective (or mood) disorders of some description, and of these, more than 2 million suffer the severe form of manic-depressive illness. However, fewer than one third of these millions ever receive treatment or even recognize that their misery could be relieved. This is a remarkable fact. Another intriguing statistic is that for those who do seek professional care, it may take up to ten years and three doctors to make the correct diagnosis. The usual justification for this extraordinary situation—so distinct from other serious medical illnesses—is a lack of public and professional education. But another major determinant of this collective blind spot lies in the nature of mood disorder itself. It stubbornly resists voluntary control. Thus, because moods develop from our emotions, and because emotional life lies at the very core of being a person, to accept that emotion and mood can be “dis-ordered” calls into question the very experience that most of us take for granted—the presence of a defined, predictable, and unique subjective entity that we fondly refer to as the intuitive “self.” When emotion and mood are disturbed, it is the familiarity and stability of this personal being that is threatened. Fortunately, an understanding of how the brain works can be helpful here. It is now accepted knowledge that emotional communication, thinking memory, and the maintenance of the body’s housekeeping are all intertwined and regulated by the coordinated activity of the limbic brain. It is this triad of behavioral activity (emotion, thinking, and the body’s daily rhythms) that becomes disturbed in the affective disorders. When mood regulation, memory and decision making, and the rhythmic functions of the body are together persistently disturbed over an extended period, resulting in a profound disturbance of personal activity and social function, the probable explanation is one of illness, not a lack of self-control.
Compared with many other human ailments, such profound disorders of mood are common afflictions. Just how prevalent we consider them to be depends partly on how we define them, but by the diagnostic criteria of the American Psychiatric Association they are common. By reasonable estimates 12 to 15 percent of women and 8 to 10 percent of men in America will struggle with a serious mood disorder during their lifetime. Their illness will impinge painfully upon family members and the many colleagues and friends with whom they share their daily lives. The economic impact on society is enormous—it has been estimated to exceed $40 billion each year in the United States alone, a social burden greater than that of heart disease. Adding to this, in the absence of treatment, is the common complication of addiction to drugs, alcohol, or both, which worsens mood disorders and compounds their social consequences. Of even greater significance is the extraordinarily high mortality of people who suffer mood disorders, whose suicide rate is 35 times greater than that of the general population. During periods of profound grief and in moments of unusual joy, we may each catch a glimpse of these states of disordered and disregulated mood. In their persistent form, however, mania and melancholia are moods that stand apart from common experience. They are serious medical illnesses that reflect a disregulation of the sentinel activities of the limbic brain.
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