Chapter 3 Theories of stress The Stimulusbased Model

Chapter 3 Theories of stress

The Stimulus-based Model of stress • Stress is interpreted as a stimulus, a life event or a group circumstances which may awakens normal and/or psychological reactions, which may increase the vulnerability of the individual to disease. • Both positive and negative life events are considered stressful. (Papathanasiou, Tsaras, Neroliatsiou, & Roupa, 2015)

The Stimulus-based Model of stress Sources of stress Examples Biological illness, surgery, pain, exposure to excessive cold or heat, intense muscle activity, sensory overload (e. g. noise pollution), accident. Chemicals medications, toxic substances, contaminated food and water. Microbial viruses, bacteria, parasites. Psychological real, fantastic or predicted unpleasant events e. g. illness, death, separation, (Holmes, 1978)

The Stimulus-based Model of stress Sources of stress Examples Developmental Premature birth, anatomical defects, growth inhibition, childhood or thirdage. Socio-cultural disturbed interpersonal relationships, social competition, business pressures, and economic difficulties, rapid changes in social and moral values, immigration, (Holmes, 1978)

The Transactional Model of Stress • Based on theory of Lazarus (1995) , who focused on the fact that there are differences among people in interpretation of stress as a stimulus or as a response. • Lazarus (1978) points out that people and groups of people differ in sensitivity and vulnerability to certain types of events, as well as in the interpretation and in the respond to those events. • Lazarus model (1983) is taking into account the cognitive processes that mediate between stimulus and response, as well as the factors affecting these processes

The Transactional Model of Stress • Lazarus (1966) cognitive evaluation theory focuses on the individual, the environment and on the simultaneous cognitive evaluation of environmental demands and stimulus response options. • According to this theory (1988, 1991), a number of external and internal information arriving daily in the neurocognitive level of the body which are interpreted by the process of cognitive evaluation. • Cognitive evaluation is the process of judgment by which, the level of adjustment methods available that each person has, is recognized. It includes identifying available resources and options, which will help the person to negotiate with potential or actual demands

What is Cognitive Appraisal? • Cognitive appraisal occurs when a person considers 2 major factors that majorly contribute in his response to stress. • The threatening tendency of the stress to the individual, and • The assessment of resources required to minimize, tolerate or eradicate the stressor and the stress it produces • Cognitive appraisal is divided into 2 types or stages: primary and secondary appraisal. (Lazarus & Folkman, 1984)

Cognitive Appraisal • Primary Appraisal • Secondary Appraisal • “What does this • “I can do it if I do my best”can it • stressor and/ or situation mean? ”, and, “How influence me? ” • “If this way fails, I can always try • primary cognitive appraisal is to classify whether theanother method” stressor or the situation is a threat, a challenge or a harm-loss. • “I can’t do it; I know I will fail” • Secondary appraisal actually happens simultaneously with the primary appraisal

Cognitive Appraisal • Three types of cognitive appraisal: • Harm refers to the (psychological) damage or loss that has already happened. • Threat is the anticipation of harm that may be imminent. • Challenge results from demands that a person feels confident about mastering. • These different kinds of psychological stress are embedded in specific types of emotional reactions, thus illustrating the close conjunction of the fields of stress and emotions. (Lazarus & Folkman, 1984)

The Transactional Model of Stress • Coping is `the cognitive and behavioral efforts made to master, tolerate, or reduce external and internal demands and conflicts among them (Folkman & Lazarus, 1980). • Coping is the perceived and behavioral effort in order to adjust in specific external or internal requirements, which exceed the individuals’ management resources (Folkman & Lazarus, 1991).

Types of Coping • Coping that is focusing in the problem • Emotion-focused • Problem-focused Coping • Indicating to the efforts for improving some. Coping situation by creating changes or taking measures • Emotional centered coping • Includes thoughts and actions that are relieving the feeling. • This coping strategy does not improve the situation, but by using it the person feels better. (Grandinetti, 2002)

Stress and Emotions Negative Mix Positive Emotion Valence Emotion • Anger • Hope • Happines • Fright • Compass s • Anxiety ion • Pride • Guilt • Relief • Shame • Love • Sadness • Envy • Jealousy • Disgust (Lazarus, 1991)

The Response-based Model of stress • Stress is interpreted as a response. • The definition of stress as a response was developed and described by Selye, who defined stress as a nonspecific response of the body to any kind demands applied on it. • Selye’s model is called General Adaptation Syndrome (GAS). Selye in order to differentiate the cause of stress from the response to this introduced the term ¨ stressor¨ naming so any factor can cause stress and affect the balance of the individual. • “Its not stress that kills us, it is our reaction to it. ” (Selye, 1965)

Hans Selye • Studied the effects of long-term (chronic) stress • Stress is- “The nonspecific response of the body to any demand made upon it” • Summarized his findings by proposing a three-phase process called the general adaptation syndrome • alarm reaction • stage of resistance • stage of exhaustion

The general adaptation syndrome (GAS) • This full whole body response GAS is manifested by releasing certain hormones, which resulted is changes in the structure and chemical composition of the body. • Local adaptation syndrome – LAS -a portion stress reaction/ response of the body or of an organ (Selye, 1965; 1976)

GAS • Selye’s first definition of stress was “the non-specific neuroendocrine response of the body” (Selye 1936, . (1976 , 1956 • Later on he dropped “neuroendocrine” because he realized that in addition to the involvement of the neuroendocrine system, almost every other organ system (e. g. especially the cardiovascular, pulmonary, and renal systems) is affected in one or several stages of the stress response, i. e. in the alarm reaction, stage of resistance and/or stage of exhaustion (Selye 1956, 1971, 1974). • He emphasis on non-specificity as the main characteristics of stressors, i. e. various agents that

Specific and non-specific (stressor) effect of various agents (Szabo, Tache, & Somogyi, 2012, p. 475)

The GAS • Alarm reaction: Initial response and is viewed as a “call to arms” of the body’s defenses. • Stage of resistance: The body mobilizes defense mechanisms to provide maximunm resistance to the threat. • Stage of exhaustion: All the body’s resources are depleted and (Rosch, 2008) inability to maintain

Alarm • Releases of adrenaline • Muscle tense, heart beat faster, the breathing and perspiration increases, the eye dilate, the stomach may clench.

Resistance / Adaptation • Causes of stress continues body respond to long term protection • Further secretion of hormones blood sugar and BP • Adrenal cortex produces “corticosteroids” • Overuse of body defense mechanism fatique, concentration lapses, irritability, and lethargy disease

Exhaustion • The body has run out of its reserve of body energy and immunity. • Mental, physical, and emotional resources suffer heavily. • The body experiences “adrenal exhaustion”. • Adrenal becomes deplete blood sugar stress tolerance, progressive mental and physical exhaustion, illness, and collapse.

Criticisms of Selye’s GAS • Stress has too many ambiguous meanings • Stress is an abstraction—it has no real independent existence • Stress has been applied to both the agent and the consequence • Stress response cannot be both specific and nonspecific • There have been few attempts to arrive at a consensus definition and operationalization for the term stress • Stress definition and the GAS do not take into (Mason, 1971)

Walter Cannon- Harvard Medical School • First to describe the effects of acute stress • Termed this stress reaction as the fight-or-flight response • A primitive response that quickly increases heart rate, respiration, blood pressure, and serum cholesterol

“fight or flight” • Alarm reaction occurs within 6 -36 hours • Initial “fight or flight” – Marked stimulation of the sympathetic nervous system and outpouring of adrenaline from the adrenal core or medulla. • Quicker blood clotting minimizes excess loss from hemorrhage, blood flow is shunted away from the stomach and gut to the large muscles of the extremities to increase tension that provides greater strength in combat or speed of flight away from a scense of potential peril. A rise in HR and BP furnishes more oxygen and nutrients to the brain to improve decision making, pupillary dilatation increased the(Rosch, 2008) range of vision, etc. to help coping with physical

Pituitary stimulation • Selye demonstrated role of pituitary stimulation of the adrenal during stress. • Resulted in secretion of glucocorticoid (cortisone & cortisol) from adrenal cortex. These augmented the rise in blood sugar and BP and increased production of stomach acid. Adrenocortical hormones has antiinflammatory effects: Adrenal enlargement (Hypertophy of cortex), stomach ulcerations, atrophy of thymus, lymph nodes. Cortisol – immunosuppressant effects. (Rosch, 2008)

Triad of the “General Alarm Reaction” normal Stressed Adrenals Thymus Iliac lymph nodes Gastric mucosa Blood (Selye, 1952) (A) Adrenals, (B) Thymus, (C) Iliac lymph nodes, (D) Gastric mucosa of normal rat (left); And one which was exposed to frustrating mental stress of being immobilized on metal broad for 24 h

How stress effects the body!!

Allostasis and Allostatic Load Theories • Homeostasis is the regulation of the body to a balance, by single-point tuning such as blood oxygen level, blood glucose, or blood p. H. • “Allostasis” proposes maintenance of stability outside of the normal homeostatic range where an organism must vary all the parameters of its physiological systems to match them appropriately to chronic demands (i. e. , reset the system parameters to a new set point). • The main hormonal mediators of the stress response in this situation are cortisol & epinephrine (adrenaline). They have both protective and damaging effects on (Mc. Ewen, 1998, 2000; Sterling & Eyer, 1988; Mc. Ewen & Wingfield, 2003) the body.

Allostasis and Allostatic Load Theories • Mc. Ewen (2000) identifies a number of physiological indicators for determining allostatic load. • These include systolic and diastolic blood pressures, high-density lipoproteins (HDL) and total cholesterol, glycosylated hemoglobin (Hb. A 1 c) levels of glucose metabolism over time, serum dihydroepiandrosterone (DHEA-S), 17 -Hydroxycorticosteroids or 24 -hour urinary cortisol excretion, and overnight urinary noradrenaline and adrenalin excretions. • Cortisol, noradrenalin, and DHEA are identified as the four primary mediators (Mc. Ewen, 1998, 2000; Sterling & Eyer, 1988; Mc. Ewen & Wingfield, 2003

Allostatic Load: "the wear and tear on the body" which grows over time when the individual is exposed to repeated or chronic stress. It represents the physiological consequences of chronic exposure to fluctuating or heightened neural or neuroendocrine response that results from repeated or chronic stress. (Juster, Mc. Ewen & Lupien, 2010)

Allostatic Load

SYMPTOMS OF STRESS • • Physical symptoms Mental symptoms Behavioural symptoms Emotional symptoms

PHYSICAL SYMPTOMS • • Sleep pattern changes Fatigue Digestion changes Loss of sexual drive Headaches Aches and pains Infections Indigestion • • Dizziness Fainting Sweating & trembling Tingling hands & feet Breathlessness Palpitations Missed heartbeats

MENTAL SYMPTOMS • • • Lack of concentration Memory lapses Difficulty in making decisions Confusion Disorientation Panic attacks

BEHAVIOURAL SYMPTOMS • • Appetite changes - too much or too little Eating disorders - anorexia, bulimia Increased intake of alcohol & other drugs Increased smoking Restlessness Fidgeting Nail biting Hypochondria

EMOTIONAL SYMPTOMS • • • Bouts of depression Impatience Fits of rage Tearfulness Deterioration of personal hygiene and appearance