stress test or exercise electrocardiography, in medicine, a test that evaluates the performance of the heart by subjecting it to controlled amounts of physical stress. Such tests, which include walking on a treadmill, measure the heart's reaction to an increased demand for oxygen. The test ends when the patient reaches a predetermined heart rate or experiences chest pain or fatigue. See electrocardiography.

stress: see strength of materials.

repetitive stress injury or repetitive strain injury (RSI), injury caused by repeated movement of a particular part of the body. Often seen in workers whose physical routine is unvaried, RSI has become epidemic since computers have entered the workplace in large numbers. Many RSIs develop when the sheaths that cover muscle tendons swell and press on nerves. Constant typing can cause one form of RSI, carpal tunnel syndrome, a sometimes disabling pain and tingling in the thumb and first two fingers. It is caused by swelling and pressure on the median nerve passing through the wrist. Other common problems are rotator cuff injury, from overuse of the shoulder; tennis elbow, inflammation of a tendon in the elbow from overuse of the forearm; and back injuries from repeated heavy lifting. A 1998 report by the National Academy of Sciences in the United States called RSI a serious national problem, with financial costs ranging up to $20 billion annually.

Treatment of RSI usually begins with attempts to change the conditions that caused the injury. Often, exercises and anti-inflammatory drugs are prescribed; in some cases surgery is necessary. Many workers' compensation cases and lawsuits relating to RSI have been brought against employers and product manufacturers. To avoid the high costs of RSI, some businesses have introduced ergonomic workstations and enforced rest periods.

post-traumatic stress disorder (PTSD), mental disorder that follows an occurrence of extreme psychological stress, such as that encountered in war or resulting from violence, childhood abuse, sexual abuse, or serious accident. The stressful event is usually followed by a period of emotional numbness and denial that can last for months or years. After that period, symptoms such as recurring nightmares, "flashbacks," short-term memory problems, insomnia, or heightened sensitivity to sudden noises may begin. In some cases outbursts of violent behavior have been observed. The usual treatment for PTSD is individual psychotherapy, including anxiety management, or group psychotherapy with others who have the disorder. Some antianxiety and antidepressant drugs are being studied for their effectiveness.

Certain traits (a history of depression, shyness, impulsivity) appear to heighten a person's risk of experiencing PTSD after a traumatic event. In those who do experience it, there is growing evidence that actual physical changes occur in the brain. The hippocampus, a structure that lies deep in the brain and that is associated with memory, has been found to be smaller in PTSD victims. It has been hypothesized that excesses of cortisol, a steroid hormone released during periods of extreme stress, may damage nerve fibers in the area or actually kill the nerve cells. However, the role of cortisol is not completely understood; studies of concentration camp survivors found abnormally low levels of cortisol rather than abnormally high levels.

Post-traumatic stress disorder was referred to as "shell shock" after World War I and as "battle fatigue" after World War II and was traditionally thought of as a condition of war veterans. Studies of Vietnam veterans and Nazi concentration camp survivors have added greatly to the knowledge of PTSD. The National Vietnam Veterans Readjustment Study (1988) estimated that 31% of the males and 27% of the females who served in the Vietnam War had symptoms of PTSD. Estimates of civilian populations put the rate of PTSD at 10% (women) and 5% (men) in the 15 to 54 age group. Childhood sexual abuse, sexual abuse, and assault are common causes of PTSD in both military and nonmilitary women. In 1989 the U.S. Congress created the National Center for Post-Traumatic Stress Disorder for the study and treatment of PTSD.

Storm and Stress: see Sturm und Drang.

In psychology, a state of bodily or mental tension resulting from factors that tend to alter an existent equilibrium. Stress is an unavoidable effect of living and is an especially complex phenomenon in modern technological society. It has been linked to coronary heart disease, psychosomatic disorders, and various other mental and physical problems. Treatment usually consists of a combination of counseling or psychotherapy and medication.

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Psychological reaction occurring after a highly stressful event and typically characterized by flashbacks, recurrent nightmares, and avoidance of reminders of the event; depression and anxiety are often present. Traumatic events that can lead to PTSD include automobile accidents, rape or assault, military combat, torture, and such natural disasters as floods, fires, or earthquakes. Long-term effects can include marital and family problems, difficulties at work, and abuse of alcohol and other drugs. Antidepressant medication and psychotherapy, including group therapy, are used in treating the disorder.

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Sturm und Drang(German; “storm and stress”)

German literary movement of the latter half of the 18th century characterized by a revolt against what the writers saw as the Enlightenment cult of rationalism and the sterile imitation of French literature. It exalted nature, intuition, impulse, instinct, emotion, fancy, and inborn genius as the wellsprings of literature. Influenced by Jean-Jacques Rousseau, Johann Gottfried Herder, and others, it took its name from the h1 of a play by Friedrich von Klinger (1752–1831). Dramatic works were the movement's most characteristic product. Its most gifted representatives were Friedrich Schiller and Johann Wolfgang von Goethe, whose Sorrows of Young Werther (1774) epitomizes its spirit.

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