In psychology, stress is a feeling of emotional strain and pressure. Stress is a form of psychological and mental discomfort. Small amounts of stress may be beneficial, as it can improve athletic performance, motivation and reaction to the environment. Excessive amounts of stress, however, can increase the risk of strokes, heart attacks, ulcers, and mental illnesses such as depression and also aggravate pre-existing conditions.
Psychological stress can be external and related to the environment, but may also be caused by internal perceptions that cause an individual to experience anxiety or other negative emotions surrounding a situation, such as pressure, discomfort, etc., which they then deem stressful.
Hans Selye (1974) proposed four variations of stress. On one axis, he locates good stress (eustress) and bad stress (distress). On the other is over-stress (hyperstress) and understress (hypostress). Selye advocates balancing these: the ultimate goal would be to balance hyperstress and hypostress perfectly and have as much eustress as possible.
The term "eustress" comes from the Greek root eu- which means "good" (as in "euphoria"). Eustress results when a person perceives a stressor as positive. "Distress" stems from the Latin root dis- (as in "dissonance" or "disagreement"). Medically defined distress is a threat to the quality of life. It occurs when a demand vastly exceeds a person's capabilities.
Causes
Neutrality of stressors Stress is a non-specific response. It is neutral, and what varies is the degree of response. It is all about the context of the individual and how they perceive the situation. Hans Selye defined stress as "the nonspecific (that is, common) result of any demand upon the body, be the effect mental or somatic." This includes the medical definition of stress as a physical demand and the colloquial definition of stress as a psychological demand. A stressor is inherently neutral meaning that the same stressor can cause either distress or eustress. It is individual differences and responses that induce either distress or eustress.
Types of stressors A stressor is any event, experience, or environmental stimulus that causes stress in an individual. These events or experiences are perceived as threats or challenges to the individual and can be either physical or psychological. Researchers have found that stressors can make individuals more prone to both physical and psychological problems, including heart disease and anxiety.Pastorino, E. & Doyle-Portillo, S. (2009). What is Psychology?. 2nd Ed. Belmont, CA: Thompson Higher Education.
Stressors are more likely to affect the health of an individual when they are "chronic, highly disruptive, or perceived as uncontrollable". In psychology, researchers generally classify the different types of stressors into four categories: 1) crises/catastrophes, 2) major life events, 3) daily hassles/microstressors, and 4) ambient stressors. According to Ursin (1988), the common factor between these categories is an inconsistency between expected events ("set value") and perceived events ("actual value") that cannot be resolved satisfactorily, which puts stress into the broader context of cognitive-consistency theory. For scientific research, several laboratory and clinical stress tests with well-defined stressors have been developed.
Crises/catastrophes This type of stressor is unforeseen and unpredictable and, as such, is completely out of the control of the individual. Examples of crises and catastrophes include: devastating natural disasters, such as major floods or earthquakes, wars, pandemics, etc. Though rare in occurrence, this type of stressor typically causes a great deal of stress in a person's life. A study conducted by Stanford University found that after natural disasters, those affected experienced a significant increase in stress level. Combat stress is a widespread acute and chronic problem. With the rapid pace and the urgency of firing first, accidental killings of friendly forces (or fratricide) may occur. Prevention requires stress reduction, emphasis on vehicle and other identification training, awareness of the tactical situation, and continual risk analysis by leaders at all levels.Headquarters, Department of the Army (1994). Leader's Manual for Combat Stress Control, FM 22–51, Washington DC.
Major life events Common examples of major life events include: marriage, going to college, death of a loved one, birth of a child, divorce, moving houses, etc. These events, either positive or negative, can create a sense of uncertainty and fear, which will ultimately lead to stress. For instance, research has found the elevation of stress during the transition from high school to university, with college freshmen being about two times more likely to be stressed than final year students. Research has found that major life events are somewhat less likely to be major causes of stress, due to their rare occurrences.
The length of time since occurrence and whether or not it is a positive or negative event are factors in whether or not it causes stress and how much stress it causes. Researchers have found that events that have occurred within the past month generally are not linked to stress or illness, while chronic events that occurred more than several months ago are linked to stress and illness and personality change. Additionally, positive life events are typically not linked to stress and if so, generally only trivial stress while negative life events can be linked to stress and the health problems that accompany it. However, positive experiences and positive life changes can predict decreases in neuroticism.
Daily hassles/microstressors This category includes daily annoyances and minor hassles. Examples include: making decisions, meeting deadlines at work or school, traffic jams, encounters with irritating personalities, etc. Often, this type of stressor includes conflicts with other people. Daily stressors, however, are different for each individual, as not everyone perceives a certain event as stressful. For example, most people find public speaking to be stressful, but someone who has experience with it will not.
Daily hassles are the most frequently occurring type of stressor in most adults. The high frequency of hassles causes this stressor to have the most physiological effect on an individual. Carolyn Aldwin, Ph.D., conducted a longitudinal study on older men (mean age ca. 66 years at the time of first stress assessment) at the Oregon State University that examined the perceived intensity of daily hassles on an individual's mortality. Aldwin's study concluded that there is a strong correlation between individuals who rate their hassles as very intense and a high level of mortality. One's perception of their daily stressors can have a modulating effect on the physiological impact of daily stressors.
There are three major psychological types of conflicts that can cause stress. The approach-approach conflict, occurs when a person is choosing between two equally attractive options, i.e. whether to go see a movie or to go see a concert. The avoidance-avoidance conflict, occurs where a person has to choose between two equally unattractive options, for example, to take out a second loan with unappealing terms to pay off the mortgage or to face foreclosure on one's house. The approach-avoidance conflict, occurs when a person is forced to choose whether or not to partake in something that has both attractive and unattractive traits such as whether or not to attend an expensive college (meaning taking out loans now, but also meaning a quality education and employment after graduation).
Travel-related stress results from three main categories: lost time, surprises (an unforeseen event such as lost or delayed baggage) and routine breakers (inability to maintain daily habits).
Ambient stressors As the name implies, these are global (as opposed to individual) low-grade stressors that are a part of the background environment. They are defined as stressors that are "chronic, negatively valued, non-urgent, physically perceptible, and intractable to the efforts of individuals to change them". Typical examples of ambient stressors are pollution, noise, crowding, and traffic. Unlike the other three types of stressor, ambient stressors can (but do not necessarily have to) negatively impact stress without conscious awareness.
Organisational stressors Studies conducted in military and combat fields show that some of the most potent stressors can be due to personal organisational problems in the unit or on the home front.Headquarters, Department of the Army (2006). Combat and Operational Stress Control, FM 4-02.51, Washington, DC, p. 9 Stress due to bad organisational practices is often connected to "toxic leadership", both in companies and in governmental organisations.Whicker, Marcia Lynn. Toxic leaders: When organizations go bad. Westport, CT. Quorum Books. 1996.
Stressor impact Life events scales can be used to assess stressful things that people experience in their lives. One such scale is the Holmes and Rahe Stress Scale, also known as the Social Readjustment Rating Scale, or SRRS. Developed by psychiatrists Thomas Holmes and Richard Rahe in 1967, the scale lists 43 stressful events.
To calculate one's score, add up the number of "life change units" if an event occurred in the past year. A score of more than 300 means that individual is at risk for illness, a score between 150 and 299 means risk of illness is moderate, and a score under 150 means that individual only has a slight risk of illness.
Life EventLife Change UnitsDeath of a spouse 100Divorce 73Marital separation 65Imprisonment 63Death of a close family member 63Personal injury or illness 53Marriage 50Dismissal from work 47Marital reconciliation 45Retirement 45Change in health of family member 44Pregnancy 40Sexual difficulties 39Gain a new family member 39Business readjustment 39Change in financial state 38Death of a close friend 37Change to different line of work 36Change in frequency of arguments 35Major mortgage 32Foreclosure of mortgage or loan 30Change in responsibilities at work 29Child leaving home 29Trouble with in-laws 29Outstanding personal achievement 28Spouse starts or stops work 26Begin or end school 26Change in living conditions 25Revision of personal habits 24Trouble with boss 23Change in working hours or conditions 20Change in residence 20Change in schools 20Change in recreation 19Change in church activities 19Change in social activities 18Minor mortgage or loan 17Change in sleeping habits 16Change in number of family reunions 15Change in eating habits 14Vacation 13Minor violation of law 10
A modified version was made for non-adults. The scale is below.