Extrait
Learning About Stress and Your Life
The real voyage of discovery consists not in seeking new lands, but seeing with new eyes.
–Marcel Proust
One
How Do You Respond to Stress?
The awareness that health is dependent upon habits that we control makes us the first generation in history that to a large extent determines its own destiny.
—Jimmy Carter
Stress and Our Ancestors
We live in a new age of anxiety, century of stress, and era of terrorism. Once the name Columbine brought to mind only a beautiful mountain flower and September 11 was just another day on the calendar. The history books that our grandchildren read will speak of the alarming increases in health and social problems related to the tensions and stress of our times. You may well ask, has man always been nervous and anxious? The plays of Shakespeare included many examples of the stress response. One of the most respected medical textbooks of the 1600s gave excellent descriptions of anxiety states. In fact, our nervous responses can be traced to the prehistoric cave dweller.
Imagine a cave dweller sitting near a small fire in the comfort of a cave. Suddenly, in the light of the fire, up comes the shadow of a saber-toothed tiger. The body reacts instantly. To survive, the cave dweller had to respond by either fighting or running. A complex part of our brains and bodies called the autonomic nervous system prepared the cave dweller for fight or flight. This nervous system was once thought to be automatic and beyond our control. Here is a partial list of the responses set up by the autonomic nervous system and how you may recognize them from your own experience.
1.Digestion slows and blood is redirected to the muscles and the brain. It is more important to be alert and strong in the face of danger than to digest food. Have you ever felt this as butterflies in your stomach?
2.Breathing gets faster to supply more oxygen for the needed muscles. Can you remember trying to catch your breath after being frightened?
3.The heart speeds up and blood pressure soars, forcing blood to parts of the body that need it. When was the last time you felt your heart pounding?
4.Perspiration increases to cool the body and release a scent signaling preparation for a fight. This allows the body to burn more energy and warns others of danger. Do you use extra deodorant when you know you are going to be under stress?
5.Muscles tense to prepare for rapid action and form muscle “armor” to slow tooth, fist, or spear. Have you ever had a stiff back or neck after a stressful day?
6.Chemicals are released to make the blood clot more rapidly. If injured, this clotting can reduce blood loss. Have you noticed how quickly some wounds stop bleeding?
7.Sugars and fats pour into the blood to provide fuel for quick energy. Have you ever been surprised by your strength and endurance during an emergency?
The cave dweller lived in the jungle or the wilderness and faced many environmental stressors. Often these were immediate, life-threatening events involving dangerous animals or human enemies. For the cave dweller, this fight-or-flight response was very valuable for survival.
Stress and Our Modern World
We have the same automatic stress responses that the cave dweller used for dangerous situations, but now we are seldom faced with a need for fight or flight. If a cat is threatened, it will arch its back. A deer will run into the bush. When we are threatened, we brace ourselves, but we often struggle to contain our nervous reactions because the threat is not usually one of immediate physical harm. Bosses, budgets, audiences, deadlines, and examinations are not life-threatening, but sometimes we feel as though they are.
Smaller stressors and briefer stress responses can add up to hundreds a day. These can be parts of our lives that we hardly notice and almost take for granted. If you work in an office, stress may accumulate with every ring of the telephone and every meeting you squeeze into your already busy day. If you are a homemaker, all the endless tasks you alone have to complete can mount up just as quickly and take just as much of a toll as those faced in the office.
Our ability to think of the past and imagine the future is still another way in which stress responses can be triggered at any time and in any place. In addition, distance is no longer a buffer. Turning on a television or a computer makes us instantly aware of wars, famine, disasters, political unrest, economic chaos, and frightening possibilities for the future.
The rate of change in our lives is accelerating. We need only to read Alvin Toffler’s classic Future Shock or James Gleick’s Faster: The Acceleration of Just About Everything to realize that the unexpected has become a part of our everyday lives. These unexpected situations are not ones we can overcome physically. Tigers are seen primarily in zoos, but it is as if we see their stripes and sharp teeth manifested in all too many ways in our everyday world.
Not only do we seem to trigger our stress response more often, but also most situations do not provide an outlet for the extra chemical energy produced by our bodies. The fight-or-flight response is not useful for most of the stress situations in modern life because we have few physical battles to fight and almost no- where to run. In the past, the demands for fulfilling basic needs for food and safety made good use of our heightened arousal. Today, few of these outlets are available.
We are influenced not by “facts” but by our interpretation of facts. —Alfred Adler
Physical Stress Versus Emotional Stress
When we think about what has happened or what might happen, we cannot run from our anxieties or physically attack our fears. We are undergoing emotional stress. The body has only limited ways of using the output of its various stress reactions to cope with emotional stress.
Physical stress is different from emotional stress. Even exercise triggers a stress response. In fact, for many years, scientists relied on the research in exercise physiology as a basis for understand- ing the effects of both psychological and physical stress upon the body. Although the effects of physical and emotional stress are similar, we now know that there are differences between them. Many hormones are elevated during the stress response. Three of them are norepinephrine, epinephrine, and cortisol. Norepinephrine and epinephrine are more commonly known as adrenaline. In response to a physical stressor, such as extremes in environmental temperature or stress induced by exercise, there is primarily an increase in norepinephrine. There is also a small increase in epinephrine. In response to a psychological or emotional stressor, there is also an increase in cortisol. To understand the effects of stress, we need to study the effects of each hormone that is secreted in response to a stressor. In general, norepinephrine has the greatest effect in increasing heart rate and blood pressure. Epinephrine has the greatest effect in releasing stored sugar. All of these actions tend to aid in preparation for vigorous physical activity. Cortisol acts to aid in preparation for vigorous physical activity, but it is also triggered by emotional stress. Unfortunately, one of its functions is to break down lean tissue for conversion to sugar as an additional source of energy. Cortisol also blocks the removal of certain acids in the bloodstream. When cortisol is elevated in the blood for prolonged periods of time, it causes ulcerations in the lining of the stomach because of increased acid formation. In addition, cortisol strains the brain’s cellular functioning, or, as one doctor explains, “it fries the brain.” Man, once the victorious predator, is now preying upon himself. —Hans Selye
Other Effects of Emotional Stress
Even if we could somehow burn off all the chemicals produced by emotional stress, upsetting psychological distress can interfere with productivity, learning, and interpersonal relationships. If our stress reactions increase, we become less and less able to handle even minor stress. Usually our ability to interact with and understand other people is also disrupted. We can exhaust our adaptive energy reserves and become more susceptible to diseases. It is clear that for life in the twenty-first century, our fight-or-flight and emotional stress mechanisms are often both unnecessary and harmful.
Balancing Emergency and Maintenance Systems
The autonomic nervous system has two divisions. One division is called the sympathetic nervous system and the other is the parasympathetic nervous system. Let’s return to the caveman sitting in front of his fire. The caveman’s response to the tiger included increased heart rate and breathing. These responses were automatic and controlled by the sympathetic nervous system. The parasympathetic nervous system influences the body in ways that are almost the exact opposite of those of the sympathetic nervous system. For example, the parasympathetic nervous system decreases heart rate, slows breath- ing, retards perspiration, and accelerates stomach and gastro- intestinal activity for the proper digestion of food.
Caesar did not merit the triumphal car more than he that conquers himself.
—Ben Franklin
If the sympathetic division can be thought of as an emergency system, the parasympathetic division can be thought of as a maintenance system. This maintenance system is responsible for the conservation and replenishment of energy. Scientists have evidence to sug- gest that our parasympathetic nervous system can be activated through relaxation procedures such as are used in stress management training programs. Maybe we can all learn to replace fight-or-flight responses with what have been called stay-and-play responses.
Hans Selye and the General Adaptation Syndrome
Dr. Hans Selye is often referred to as the “father of stress research.” His pioneering work demonstrated that every demand on the body evokes not only physiological responses specific to the demand but also the nonspecific and uniform stress responses we have already discussed. Selye called the non-specific reactions to stress the general adaptation syndrome. It consists of three stages: alarm reaction, resistance, and exhaustion.
During the alarm reaction, the stressor activates the body to prepare for fight or flight. Both electrical and hormonal signals are involved in mobilizing the energy needed for an emergency. Heart rate, breathing, and perspiration increase. The pupils of the eyes dilate. Adrenaline and cortisol are released. Stored energy floods the bloodstream.
According to Selye, if the stress is strong enough, death may result during the alarm reaction. In fact, the immune response is suppressed as energy is devoted to fight or flight.
During the resistance stage of adaptation to stress, the signs of the alarm reaction are diminished or nonexistent. The im- mune system bounces back and resistances to noxious stimuli and illnesses such as infectious diseases increase above their normal level. Hormones that reduce inflammation from injuries also increase.
If the stressful stimuli or responses persist, the stage of resistance is followed by a stage of exhaustion. By this stage, the exposure to a stressor has nearly depleted the organism’s adaptive energy. The signs of the initial alarm reaction reappear, but they do not abate. Resistance decreases, vulnerability increases, and illness or death may follow.
The general adaptation syndrome has great importance as an early theory linking stress and disease. It stimulated much research contributing to our understanding of stress and resistance as factors in every illness. Stress may interfere with our ability to resist most diseases, but we now also know that the ability to manage stress adaptively can be learned. When this skill is used, stress is enjoyed as a challenge rather than dreaded as a threat.
Hope is the feeling you have that the feeling you have isn’t permanent.
—Jean Kerr
Female Stress and the Tending Instinct
Most of our biological understanding of the stress response is based on research using male rats because the hormones of female rats fluctuate rapidly and complicate the results. Prior to the government’s mandate in 1995 that human research studies had to include both sexes, less than 20 percent of the participants in biological stress research were women. In addition, men conducted most of this research. Shelley E. Taylor, a UCLA psychologist, recognized that this male bias might be one of the few “big mistakes left in science.”
The fight-or-flight response might describe the male’s life- saving response to attack, but this arousal might be only part of the solution for females with offspring. Flight by a mother would be impaired with children in tow and could be fatal for children left unprotected. The fight might be necessary but could be fatal to the mother and her young. Evading detection and creating a community with strength in numbers might be far safer.
Taylor proposed a “tending instinct” for women that is revealed in a biologically based “tend-and-befriend response.” This nurturing and protecting response is principally supported by oxytocin, a hormone that is best known for prompting labor and milk production. Other hormones include endogenous opioid peptides, popularly known for initiating the “runner’s high.” On the other side, androgen hormones, such as testosterone, regulate male aggression. Joining forces and watching out for one another is important for survival of both men and women, but it may be more critical for the “nurturer sex.”
After reviewing thirty scientific studies of what men and women do in response to many different kinds of stress, Taylor concluded that all research revealed women turning to friends, neighbors, and relatives more than men did. Primitive behavior reflects the same bonds. Female primates share their food, groom each other, babysit, and join to defend their young.
The tend-and-befriend response is an exciting new discovery. Research about the response is in its infancy compared to that on the fight-or-flight response, but the implications for stress and its management are many. We have already seen how the fight-or-flight response can help or harm. It may surprise you that the tend-and-befriend response can also help or harm. Thus, women reap the benefits but also pay the cost of both stress responses.
Stress and Disease
If your doctor has recommended that you relax or take it easy, you may be suffering from a stress-related disorder. It is estimated that up to 75 percent of all visits to physicians are from people with a stress-related problem. Stress may be a major factor in causing hypertension and coronary heart disease, migraine and tension headaches, and immune and asthmatic conditions. Stress may lead to harmful habits such as smoking, drinking, or overeating, which have been shown to cause or intensify still other diseases. Stress is also suspected to aggravate chronic backache, arthritis, allergies, diabetes, hyperthyroidism, vertigo, and multiple sclerosis.
Dermatologists find that stress is a factor in many skin disorders such as hives, eczema, and dermatitis. It has also been strongly associated with many gastrointestinal disorders, including irritable colon and gastritis. Some of the excess hormones that the adrenal glands release during repeated stress responses can interfere with your body’s immunity to infection. You may then become more susceptible to bacteria and viruses such as the flu virus.
Stress and Mental Health
Stress not on...
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