Some emotions are relaxing: the calm tranquility your experience lazing under a warm sun. Some are uplifting: the pride and sense of power you experience after winning a big game. But some emotions are stressful. Tragic news (the death of a loved one), physical threats (a mugging), personal challenges (an upcoming exam), and interpersonal crises (a relationship break-up) create feelings of intense stress.

In this final section of the chapter, we’ll look at the nature of stress, how it can affect the body and your health, and how you can cope with the stresses of life.

The word “stress” can be used in three different ways. It can refer to (1) environmental events, (2) subjective feelings, and (3) bodily reactions, specifically, the body’s response to stressful events. Let’s look at all three.

ENVIRONMENTAL STRESSORS. An environmental event is called a “stressor” if it is potentially damaging to an individual. Researchers distinguish among three types of environmental stressors (Lazarus & Lazarus, 1994):

In addition to the three types of stressors, stressors—of any type—also differ in duration (Segerstrom & Miller, 2004). Acute stressors last a brief amount of time. They would include, for example, the stress of slipping and falling on the ice, or suddenly being called on in class to answer a question for which you’re unprepared. Chronic stressors are present through a prolonged period of a person’s life. They include stressors such as chronic poverty, living in a war zone, or caring for a person with a severe mental disability.

These distinctions identify different types of stressors. What specific life events, though, tend to be most stressful? Psychologists have developed lists of stressful life events, ranked according to the degree to which they disrupt established patterns of life (Holmes & Rahe, 1967). As you can see (Table 10.2), they include not only negative events (e.g., personal injury, being fired from work) but also some positive ones (e.g., an addition to the family) that require life adjustments that may present major challenges.

Have you experienced a lot of these events? Let’s hope not! They are life events that cause stress because they disrupt established patterns of life. The stress scores indicate the typical degree of disruption (Holmes & Rahe, 1967).

10.2

SUBJECTIVE STRESS. Stress must be understood not only from the outside— stressors in the environment—but also from the inside. People’s inner thoughts can determine whether any given environmental event is stressful. This is especially true for events in the social world, which can be interpreted differently by different people. A job interview may be a “valuable opportunity” to one person but a “stressful evaluation” to another. One student looks forward to classroom discussions, which she sees as a chance to show off her intelligence, whereas another is stressed out because she sees only the possibility of saying something stupid. Subjective stress is the psychological impact of a potentially stressful event from the perspective of the individual who is experiencing it.

People experience subjective stress when situational demands and personal resources are out of balance (Lazarus & Lazarus, 1994). If demands outweigh resources (“I can’t figure out these calculus problems—and the exam is tomorrow!”), stress results. Stress also can arise if the balance tips in the other direction. When personal resources greatly outweigh situational demands—for example, you’re a skilled musician stuck in a music class for beginners—people become bored, and the boredom itself can be stressful. Calm, stress-free moments arise when personal skills and environmental demands are in synch (Csikszentmihalyi, 1990).

Measures of subjective stress differ from tests designed to measure environmental stressors (see Table 10.2). Subjective stress is measured using test items such as the following (Horowitz, Wilner, & Alvarez, 1979):

These items tap personal responses to stressful circumstances. They enable psychologists to identify individual differences in subjective reactions to the same objective event.

PHYSIOLOGICAL STRESS REACTIONS. “Stress” also refers to physiological reactions. When you experience a stressor, your body reacts. It produces a stress response, a coordinated series of physiological changes that prepare you for “fight or flight,” that is, to confront or flee the stressor (Rodrigues, LeDoux, & Sapolsky, 2009).

The physiological changes that comprise the stress response occur in multiple systems within the body. Your heart rate increases, which delivers more oxygen to muscles to fuel bodily movement. Your thinking changes; signals from body to brain cause your attention to focus in on the stressor. Your immune system alters its functioning; as we discuss in detail below, this change means that stress can affect your health.

In the mid-twentieth century, the biologist Hans Selye (1950) identified the general adaptation syndrome (GAS), a sequence of physiological reactions that occur in response to stressors. The GAS consists of three stages:

The biological mechanisms that enable the body to respond adaptively to stress involve hormones, chemical substances that travel throughout the body and influence the activity of bodily organs (Chapter 3). When a stressful event occurs, hormones make intelligent use of the body’s overall energies (Sapolsky, 2004). Hormones increase the supply of blood sugar and oxygen, which gives you extra energy to either flee from or confront the stressor. They suppress physiological activities that don’t help you cope with the stressor; for example, under stress, digestive processes and sexual drives are reduced. This makes sense in evolutionary terms. Over the course of evolution, if you were under threat from a predator, that was no time to sit around digesting food or having sex.

Which exact hormones and bodily organs are involved in stress reactions? The central system is the hypothalamic–pituitary–adrenal (HPA) axis, an interconnected set of structures and hormone pathways that regulates stress response (Figure 10.16). As the name suggests, the HPA includes three structures: (1) the hypothalamus (a small structure in the lower-central area of the brain), (2) the pituitary gland (located just below the hypothalamus), and (3) the adrenal glands (which sit on top of the kidneys). A sequence of activities occurs when the hypothalamus is activated by stress (Sternberg & Gold 1997):

The HPA axis also has a feedback mechanism. Some of the cortisol from the adrenal glands makes its way back to the hypothalamus and inhibits further hypothalamic release of CRH. This prevents the body as a whole from overreacting to the stressor (Sternberg & Gold, 1997).

How does stress influence health? A primary way is through the effects of stress on the immune system.

STRESS AND THE IMMUNE SYSTEM. Your body generally is good at protecting itself. A set of bodily processes, the immune system, protects against germs, microorganisms, and other foreign substances that enter the body and can cause disease.

Stress can disrupt the normal functioning of the immune system. The link from stress to immune functioning is the HPA axis. Immune system response is affected by cortisol, the hormone released by the adrenal glands (Sternberg & Gold, 1997).

Different types of stressors have different effects on immune functioning. The key difference is whether the stressor is a short-term or long-lasting event (Sapolsky, 2004). Short-term stressors increase immune system activity. This is understandable on evolutionary grounds. If an organism is fighting or fleeing, it is at higher risk of injury, and any injury places the organism at higher risk of infection. Immune system activation, then, is adaptive; it prepares the body to fight against the infection that is relatively likely to occur (Segerstrom & Miller, 2004). Long-term, chronic stress is different. It suppresses the immune system. If you live with high levels of stress for a long period of time, your immune system cannot maintain high levels of stress response, and eventually its functioning declines to unusually low levels (Sapolsky, 2004).

A meta-analysis of more than 300 studies confirms the impact of stressful events on immune system functioning (Segerstrom & Miller, 2004). When confronted by short-term stressors, such as having to give a public speech, people’s immune systems respond adaptively. But chronic stressors—for instance, a physical disability, caring for someone with dementia, or being forced to move from one’s home due to war—cause people’s immune systems to work less well than normal.

STRESS AND HEALTH OUTCOMES. As you would expect, when the immune system is impaired, people experience poor health (Lovallo, 2005). Nurses who work for years on night shifts experience more heart disease (Kawachi et al., 1995). People who care for relatives with dementia are slower to heal from physical wounds (Kiecolt-Glaser et al., 1995). Children, too, are affected by stress. Those who grow up in poverty experience more stress and, as adults, have more cardiovascular problems and do not live as long as people from wealthier backgrounds (Cohen et al., 2010). A range of aversive childhood experiences (ACEs), including exposure to physical abuse, mental abuse, domestic violence, or other criminal behavior, predict poorer health when the child reaches adulthood (Palusci, 2013).

Psychologists have linked stress to health through two types of research strategies. One is correlational; researchers determine whether levels of stress correlate with later health outcomes. For example, in the study of marital stress, correlational findings indicate that high levels of marital distress predict high numbers of physician visits, higher levels of self-reported health problems (symptoms of colds, flu, and gastrointestinal difficulties), and higher levels of health problems affected by poor immune system functioning, such as arthritis (Kiecolt-Glaser & Newton, 2001).

Correlational studies are informative but not entirely convincing. They leave open two possibilities. One is that stress directly impacts health. The other is that stress impacts health only indirectly; for example, highly stressed people may lead more hectic lifestyles that expose them to more people and thus more viruses. This exposure—not stress itself—may affect health. The second research strategy circumvents this problem.

In the second strategy, researchers experimentally manipulate people’s exposure to viruses. Sheldon Cohen and colleagues randomly assigned participants to conditions in which they received nasal drops containing (1) a respiratory virus or (2) a simple mixture of salt and water (Cohen, Tyrrell, & Smith, 1993). Participants were quarantined in their apartments for two days before and seven days after receiving the drops. Each day, a physician examined each participant and recorded signs of illness. In addition, Cohen and colleagues measured stress. Participants indicated the number of stressful life events they were experiencing and whether they believed that these stressors exceeded their ability to cope. This sophisticated research strategy demonstrated that stress directly predicts health; among those exposed to the virus, people with more stressful lives were more likely to develop colds (Figure 10.17).

STRESS AND THE RATE OF AGING. When he served as vice president of the United States, an energetic, youthful Richard Nixon—who looked like a man in his early 40s—ran for the presidency. (Nixon lost to an even more youthful and energetic-looking John F. Kennedy.) When the Watergate scandal reached its crescendo later on, the President Nixon who resigned looked perhaps 30 years older, with greying hair, sagging skin, and a lined, worn face. But the two Nixons shown in the pair of photos differ in age not by three decades, but by only 14 years. What could have caused Nixon to age so much during that time period?

In part, it was the natural effects of aging (Olshansky, 2011). But the stress couldn’t have helped. Life stress can accelerate the rate at which people age. Stress influences aging by affecting small bits of DNA called telomeres (Epel et al., 2004).

DNA, which is contained in chromosomes in the nuclei of cells, is the molecular material that contains the genetic instructions used to build organisms. A telomere is a small strand of DNA at the end of each chromosome. Telomeres maintain a cell’s “youthfulness.” When a cell loses too much of its telomere, it cannot replicate. Evidence suggests that, when this happens, body tissues age more rapidly (Sanders & Newman, 2013).

Research shows that stress can alter the body’s internal chemistry in a way that causes telomeres to shorten (Epel et al., 2004). The researchers studied a group of mothers, some of whom experienced the stress of caring for a chronically ill child. They measured the level of stress experienced by each mother and, by analyzing blood samples, also measured telomere length. Mothers with higher levels of stress had shorter telomeres. They were old before their time.

Research on stress and telomeres reveals, once again, the intimate connections between body and mind, and the interplay among person-, mind-, and biological-level analyses in psychological science. The social context in which people live (in our example, as caregivers for someone who is chronically ill) affects mental experiences (increased feelings of stress) and thus the inner workings of the body.

How do you deal with stress? Some of the following strategies (from Internet discussions) might sound familiar:

You’re probably thinking that some of these coping strategies are better than others. You might also have noticed that they are of two different types: problem-focused and emotion-focused coping strategies.

PROBLEM-FOCUSED AND EMOTION-FOCUSED COPING. In a classic book on stress and coping, Richard Lazarus and Susan Folkman (1984) identified two primary ways in which people cope with stressful events:

Look back to the examples of coping we presented above. You can tell which type of coping each exemplifies. “Prioritize things based on importance” is problem-focused; that person is making the source of stress, school activities, more manageable. “Playing Electric Avenue and eating Grape Nerds” is emotion-focused; it does not address one’s problems, but it might put a person in a more relaxed mood.

Which way of coping is better? It depends; “coping processes are not inherently good or bad” (Folkman & Moskowitz, 2004, p. 753). Focusing on problems to be solved is often advantageous. Yet sometimes—such as when a problem is out of your control—it may be better to work on your emotional state. Problem-focused coping might be best when, for example, you have to cope with a heavy workload at the end of a busy semester. But emotion-focused coping may be the best strategy if you are dealing with the breakup of a relationship or the death of a loved one.

Research points to the advantages of coping flexibly: adjusting your coping style to the possibilities available in the situation at hand. One researcher (Cheng, 2001) measures flexibility by asking people how they have coped with a variety of different stressors that occur on different days. Some people, she finds, tend to cope in the same way from one situation to the next. Others are more flexible; they adjust coping strategies to different situations. Findings show that people who cope flexibly are less anxious when a highly stressful event, such as a major health problem, occurs (Cheng, 2003). Workers who are taught strategies for coping flexibly (e.g., using emotion-focused coping when problems seem uncontrollable) are less likely than others to become depressed when they experience stress at work (Cheng, Kogan, & Chio, 2012).

GENDER DIFFERENCES IN COPING. When it comes to coping with stress, men and women differ. To see the difference, we have to distinguish between two types of coping responses: fight-or-flight and tend-and-befriend (Taylor et al., 2000). (This distinction differs from the problem-focused/emotion-focused distinction, as you will see.)

Many members of the animal kingdom display a fight-or-flight response pattern (Cannon, 1932). A fight-or-flight response pattern is one in which an organism facing a threat does one of two things: (1) attack or (2) flee from the threat. If challenged by a predator, an animal might (1) fight or (2) run away. If challenged in an argument, you might (1) fight back verbally or (2) flee from confrontation by accepting the other person’s point of view. Organisms usually opt for flight, rather than fight, when they see themselves as incapable of fighting back successfully. (Note that both fight and flight are problem-focused strategies; a problem is confronted or avoided.)

The psychologist Shelley Taylor and colleagues (Taylor et al., 2000) explain that women often cope in ways that are neither fight nor flight. Instead, women often tend-and-befriend, a strategy defined by two coping responses:

Women are more likely than men to tend and to befriend. For example, compared with men, women have more same-sex friendships, more frequently seek support from their friends, and provide more emotional support to their friends (Taylor et al., 2000).

Why do men and women differ? Taylor suggests that biological evolution provides the answer. Across the course of evolution, females have been more heavily involved in parenting than males. During pregnancy, females carry the offspring. Afterward, they provide more biological support during nursing. For females, then, fight-or-flight often doesn’t make sense. Both fighting and fleeing are hard at advanced stages of pregnancy. Both strategies leave offspring unprotected (while the mother fights or flees). By contrast, tending to the needs of offspring helps them survive during times of stress, and befriending others creates social networks that can help to support the mother. Women have therefore evolved a tendency to tend-and-befriend that is relatively lacking in men. Taylor and colleagues (Taylor et al., 2000) outline biochemical factors that contribute to the observed gender differences in coping behavior.

SOCIAL SUPPORT. Taylor’s analysis of befriending raises a key point: When coping with stress, you don’t have to go it alone. Friends and family can reduce the impact of stressful events by providing loving care and personal assistance, or social support. Research shows that people who receive more social support during times of stress tend to experience better physical and mental health (Cohen & Wills, 1985; Taylor & Stanton, 2007).

Psychologists have identified two ways in which social support is beneficial (Cohen & Wills, 1985). One is stress buffering. When stressful events occur, support from others can lower—or “buffer”—their impact. Suppose you experience a financial crisis. Friends and family might help with both problem-focused coping (by lending you money) and emotion-focused coping (by helping to reduce your anxiety). In this way, they buffer the impact of the crisis.

Social support’s other benefit occurs even before you experience stress. Large networks of supportive friends and family increase people’s overall psychological wellbeing. Increased well-being, in turn, lowers the chances that people will experience severe negative emotions when a setback occurs (Cohen & Wills, 1985).

Research documents the impact of social support in multiple areas of life. One is intimate relationships. Psychologists suggest that one key to the success of relationships is the social support that partners provide one another (Reis & Patrick, 1996). When partners make each other feel understood and emotionally supported, relationships thrive. In a study of remarkable scope, researchers studied couples over a 10-year period (Sullivan et al., 2010). In year 1, couples went to a laboratory and discussed marital problems they were facing. Researchers coded the degree to which partners provided positive emotional social support to one another during the discussions. At year 10, the researchers determined marital status (i.e., whether each couple was still married). Social support at year 1 significantly predicted marital status at year 10. Husbands and wives who were more socially supportive at year 1 were more likely to still be husbands and wives at year 10.

Another area where social support brings benefits is parenting. Parenting can be stressful for anyone, but is particularly so for parents of children with disabilities. In one research project (Ha, Greenberg, & Seltzer, 2011), African American parents of children with disabilities such as autism (a disorder in which children fail to develop normal interactions with other people; see Chapter 14) and epilepsy (a nervous system disorder in which people experience seizures), plus a comparison group of parents whose children had no disabilities, were studied over a number of years. This group of parents was of particular interest because African American communities often contain extended families whose members provide one another with substantial social support.

A key dependent variable in this study was the emotional state of parents; the researchers measured negative emotion experienced by parents with, and without, children with disabilities. As you can see in Figure 10.18, social support buffered parents against negative emotions. Consider the parents of children with a disability. Among those with low social support, stressful negative emotions were frequent. But among those with high levels of social support, negative emotions were no more frequent than they were among other parents.