Eustress, stress and distress. stress prevention methods

Stress (from the English. Stress - load, tension; state of increased tension) - a set of nonspecific adaptive (normal) reactions of the body to the effects of various adverse factors — stressors (physical or psychological) that violate its homeostasis, as well as the corresponding state of the nervous system of the body (or organism as a whole). In medicine, physiology, psychology, there are positive ( eustress ) and negative ( distress ) forms of stress. By the nature of the impact, they emit neuropsychic, thermal, or cold (temperature), light, starvation, and other stresses (radiation, etc.).

Whatever the stress, “good” or “bad”, emotional or physical (or both), its effect on the body has common specific features.

History of the term

For the first time, the term “stress” in physiology and psychology was introduced by Walter Cannon (born Walter Cannon ^[1] ) in his classic works on the universal fight or flight response ( fight-or-flight response ) ^{[2] [3] [ 4]} .

The renowned stress researcher Canadian physiologist Hans Selye in 1936 published his first work on the general adaptation syndrome ^[5] , but for a long time avoided using the term “stress” because it was used to denote the “psychological” stress (“fight or run away "). Only in 1946, Selye began to systematically use the term "stress" for general adaptive stress.

Stress physiology

General adaptation syndrome (OSA)

For the first time, physiological stress was described by Hans Selye as a general adaptation syndrome. The term "stress" he began to use later.

“Stress is the nonspecific response of the organism to any presentation of a requirement [...] In other words, besides the specific effect, all agents acting on us also cause a nonspecific need to perform adaptive functions and thereby restore the normal state. These functions are independent of the specific effect. Non-specific requirements imposed by exposure as such is the essence of stress

- Hans Selye, "The Stress of Life" ^[6]

Back in the 1920s, while studying at the University of Prague, Selye noticed that the onset of any infection is the same (fever, weakness, loss of appetite). In this well-known fact, he saw a special property — universality, non-specificity of the response to any damage. Experiments on rats have been shown to give the same reaction both to poisoning and to heat or cold. Other researchers have found a similar reaction in people who have suffered extensive burns.

Under stress, along with elements of adaptation to strong stimuli, there are elements of tension and even damage. It is the universality of the “triad of changes” accompanying stress - a decrease in the thymus, an increase in the adrenal cortex and the appearance of hemorrhages and even ulcers in the mucous membrane of the gastrointestinal tract - which allowed G. Selye to express the hypothesis of a general adaptation syndrome (OSA), which was later called “stress”. The work was published in 1936 in the journal Nature. Years of research G. Selye and his staff and followers around the world confirm that stress is the nonspecific basis of many diseases.

Selye identified 3 stages of general adaptation syndrome:

1. anxiety reaction (mobilization of adaptive capacity - these possibilities are limited)
2. resistance stage
3. depletion stage

For each stage, characteristic changes in neuro-endocrine functioning are described.

Initially, Selye considered stress only as a destructive, negative phenomenon, but later Selye writes:

Stress is the nonspecific response of the organism to any presentation of demands. [...] From the point of view of stress response, it does not matter whether the situation we are facing is pleasant or unpleasant. What matters is the intensity of the need for adjustment or adaptation.

- Hans Selye, "The Stress of Life"

Later, Selye introduced an additional concept of “positive stress” ( Eustress ), and “negative stress” was designated as distress .

Adaptive energy

Developing the concept of stress, G. Selye in 1938 proposed the concept of short-term and medium-term adaptation (adaptation of adults at times much shorter than the lifetime), based on the concept of adaptive energy.

The concept of adaptation energy allows us to describe individual adaptation differences as differences in the distribution of adaptation energy according to the structural-functional scheme of the adaptation system (as well as in the amount of this energy). This scheme itself can be complicated, but it is the same within this species (for definiteness, Selye considers adult individuals of the same sex). In a number of specific physiological experiments, Selye showed that the redistribution of this resource increases the resistance to one factor and at the same time reduces the resistance to another. The concept of adaptation energy has acquired an "axiomatic" form (quotes mean that these axioms do not provide true axiomatics in a mathematical sense):

1. Adaptive energy is available in limited quantities, given from birth.
2. There is an upper limit on the amount of adaptation energy that can be used by an individual at any moment of (discrete) time. This amount can be concentrated in one direction or distributed between different directions of response to multiple environmental challenges.
3. There is a threshold for the impact of an external factor that must be crossed in order to trigger an adaptation response.
4. Adaptive energy can be active at two different levels of competence: the primary level at which the response generates in response to a high level factor, with high expenditure of adaptive energy and the secondary level at which the response is generated at a low level of impact, with low expenditure of adaptation energy.

In 1952, Goldstone proposed criticism and development of Selye’s theory. It complements Selye's laboratory experiments with a description of typical clinical cases confirming this picture. Goldstone argues that such a description of adaptation using adaptation energy is extremely helpful. At the same time, he refutes the first axiom, according to which the adaptation energy is present in a limited quantity, given from birth.

Goldstone proposes the concept of permanent production of adaptation energy, which can also be accumulated and stored in limited quantities, and demonstrates that this concept even better describes Selye’s experiments than the original idea of ​​constant adaptation capital. He also uses the work of Carrel ^[10] , who studied adaptation to the stimuli that lie below the anxiety threshold, and showed that such exercises nonspecifically enhance (“awaken”) the general adaptive response, which contradicts Selye’s purely expensive concept, which he later tried to overcome in its concept of eustress.

Goldstone argues that constantly incoming weak negative incentives are constantly being met and overcome by continuously acting adaptation. The initial effect of stimuli is to awaken the adaptation system and to bring it into a state of readiness for a faster and more effective response. Stronger stimuli may require a greater expenditure of adaptive energy than is produced; then the adaptation reserve is put into action, and if it is spent, then death occurs. There is a maximum possible rate of consumption of adaptive energy, and at this maximum the organism cannot cope with any additional stimulus. It describes how one stimulus can influence the individual ability of an adaptive response to other stimuli; The outcome depends on the specific situation:

1. A patient who cannot cope with the disease is able to overcome it after a moderate additional stimulus.
2. In the process of adapting to this new stimulus, he may acquire the ability to react more intensively to all stimuli.
3. As a result of a strong stimulus, the patient may not be able to adapt to an additional strong stimulus.
4. If he successfully adapts to the disease, then this adaptation can be destroyed by the impact of a second strong stimulus.
5. For some diseases (in particular, adaptation diseases), the effect of a fresh, strong stimulus can defeat the disease. This impact is always associated with risk, but it can also normalize the work of the adaptation system.

Axiom Goldstone. Adaptive energy can be produced, although its production decreases in old age, it can also be saved in the form of adaptation capital, although the capacity for this capital is limited. If an individual spends his adaptive energy faster than it produces, then he spends his adaptive capital and dies when it is completely exhausted.

Modern models of adaptation and adaptation energy are based on the idea of ​​limiting factors (first proposed in 1828 by K. Spengler and known in the application to agrocenoses after von Liebig’s works, 1840) and the evolutionary principles of optimality leading from the work of J. B S. Haldane. Adaptation is presented as an evolutionarily optimal system of distribution of adaptive energy to neutralize the most harmful factors.

Stress and pharmacology

For the treatment of depletion of the nervous system (which is caused by prolonged (chronic) and / or intense stress) use nootropic drugs. Anxiolytics and tranquilizers are used to symptomatically reduce the severity of stress.

Further development of the theory of stress

It is shown that stress (as a classical non-specific reaction in G. Selye’s description) is just one of the reactions that make up the general system of non-specific adaptation reactions of the organism, because the organism, as a more sensitive system than its constituent subsystems, reacts to different strengths and qualities. stimuli that cause homeostasis to fluctuate within, in the first place, normal values, and stress is a reaction to strong stimuli.

The effect of group stress is shown, which manifests itself in groups and populations that are in difficult conditions of existence: in a typical situation, with an increase in the adaptive load, the level of correlations increases, and as a result of successful adaptation it decreases. The greatest information about the degree of adaptation of the population to extreme or simply changed conditions is carried by correlations between physiological parameters. Based on the effect, a method of correlation adaptometry has been created ^[12] . The method is systematically used in monitoring tasks ^[13] .

The application of the multiple regression method proved the possibility of predicting the level of stress long before its occurrence in order to identify individuals (or groups of individuals) who are particularly susceptible to stress. This method allows not only to detect in advance the level of stress tolerance of a person, but also with high accuracy to predict the indicators of the level of mental and somatic stress of people under stress .

Types of stress

Eustress

The concept has two meanings - “stress caused by positive emotions” and “moderate stress that mobilizes the body.”

Distress

Negative type of stress with which the body can not cope. It undermines human health and can lead to serious illnesses. The immune system suffers from stress. People under stress are more likely to be victims of infection, since the production of immune cells drops markedly during physical or mental stress.

Emotional stress

Emotional stress is called emotional processes that accompany stress, and leading to adverse changes in the body. During stress, the emotional reaction develops earlier than others, activating the autonomic nervous system and its endocrine provision. With prolonged or repetitive stress, emotional arousal can stagnate, and the functioning of the body can be degraded .

Psychological stress

Psychological stress, as a type of stress, is understood by different authors in different ways, but many authors define it as stress due to social factors .

Using stress for interrogation or psychological manipulation

Lie detector - a device for checking the truth of a person’s words. In the program of questions for testing, methods are widely used that increase the stress on the interviewee so that he loses control over his behavior or answers.

“Interview Stress,” in personnel work, is a survey method in which the interviewer intentionally creates an atmosphere of nervousness and confuses the applicant for work with unexpected questions.

These methods are well described by the concept of "provocation" (and / or "trolling").

Common Misconceptions

Among non-specialists, there was a tendency to identify stress (and especially psychological stress) simply with nervous tension (part of the blame for the term itself, meaning “tension” in English). Stress is not just emotional excitement or nervous tension. First of all, stress is a universal physiological response to fairly strong effects, having the described symptoms and phases (from activation of the physiological apparatus to exhaustion).