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Defining & measuring stress . Assist. Prof. Merve Topcu PSY 411 Health Psychology Department of Psy chology Çankaya University 2016-2017, Fall. The Nervous System (NS) & Physiology of Stress. NS is to integrate all the body’s systems Billions of individual cells in NS called neurons
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Defining & measuring stress Assist. Prof. Merve Topcu PSY 411 Health Psychology Department of Psychology Çankaya University 2016-2017, Fall
The Nervous System (NS) & Physiology of Stress • NS is to integrate all the body’s systems • Billions of individual cells in NS called neurons • Electrically charged ions hold the potential for an electrical discharge • The electrical charge leads to therelease of chemicals called neurotransmitters (NTs) • Excitatory or inhibitory NTs • Excitatory or inhibitory messages have cumulative effect • Neurons’ threshold must be exceeded in order to be activated • If the threshold is exceeded, then neuron fires • The released neurotransmitters diffuse across the synaptic cleft
Types of neurons • Afferent neurons (Sensory neurons) • Relay information from the sensory organs to CNS (spinal cord & brain) • Efferent neurons (Motor neurons) • Impulses travel from the CNS & cause contraction of muscles of stimulation of glands and organs • Interneurons • Connect sensory neurons to motor neurons w/in the spinal cord
The Nervous System • Two major divisions of the NS • Central NS (CNS) • The brain & spinal cord • Peripheral NS • All other neurons
Peripheral Nervous System • That part of the NS lying outside of the brain & spinal column and is divided into two parts • Somatic NS • Autonomic NS (ANS)
Peripheral Nervous System • Somatic NS • Serves the skin and the voluntary muscles • Moving your fingers • Things you think to do • Motor nerves that activate muscles are part of SNS • 12 pairs of cranial nerves has role in the transmission through spinal cord
Peripheral Nervous System • Autonomic NS • Self-governing, involuntary & automatic • Outside realm of conscious or voluntary control • E.g., controlling heart rate / breathing • Can be learned to control • Primarily serves internal organs • Important in understanding responses to stress • Neurons in the ANS are activated by neurotransmitters, principally acetylcholine and norepinephrine • Complex effect on organ systems bc organs contain different neurochemical receptors • 2 divisions: • Differs both anatomically & functionally • Symphatetic NS • Parasympathetic NS
Peripheral Nervous System • Autonomic NS • 1 & 2 works reciprocally • Maintaining appropriate level of activation called allostasis • Means, different circumstances requires different levels of physiological action • Symphatetic NS • Mobilizes the body’s resources in emergency, stressful, and emotional situations • Fight / flight response (Cannon) • Parasympathetic NS • Promotes relaxation, digestion, and normal growth functions • Non-stressful situations
The Neuroendocrine System • The endocrine system consists of ductless glands distributed throughout the body • The neuroendocrine system consists of those endocrine glandsthat are controlled by and interact with the nervous system • Use hormones via bloodstream for messaging in body • may have a direct effect or may cause the secretion of another hormone
The Neuroendocrine System • Similarities forendocrine system & neuroendocrine system • Systems share, synthesize, and release chemicals • Have communication & control functions
The Neuroendocrine System • The Pituitary Gland • Excellent example of the intricate r/ship btw the NS & endocrine systems • Connected to the hypothalamus • A structure in the forebrain • Sometimes referredto as the “master gland” bc • it produces 7 hormones that affect other glands and prompt theproduction of yet other hormones • Influence secretions of tyroids, pancreas, adrenals, and gonads • Secrets growth hormone • Adenocorticotropic Hormone (ACTH) • Produced by pituitary gland • Plays an essential role in stress • When stimulated by the hypothalamus, the pituitary gland releases ACTH which acts on the adrenal glands
The Neuroendocrine System • The Adrenal Glands • located on top of each kidney • Controls salt & carbonhydrate metabolism • Secretes hormones for arousal & sleep • Contains 2 structures that produce different hormones • Each gland is composed of outer covering (the adrenal cortex, cortisol) & an inner part (theadrenal medulla, E & NE) • Both secretes hormones that are important in the response to stress • Cortisol is the most important stress hormone
The Neuroendocrine System • The Adrenal Glands • The adrenomedullary response includes activation of the adrenal medulla by SNS • Prompts thesecretion of catecholamines • A class of chemicals that contain epinephrine & noreepinephrine • Epinephrine: sometimes known as adrenaline, is produced exclusively by the adrenal medulla & accounts for about 80 % of hormone production of the adrenal glands • Noreepinephrine is produced in many places besides the adrenal medulla. It is also a NT. • Both hormones act slower than NT, acts in bloodstream and synaptic cleft, & their effect is more prolonged • Catecholamines is used as stress index (e.g., in urine)
Physiology of Stress Response – HPA Axis • Physiological reactions to stress starts w/ the perception of stress! • SNS controls mobilization of the body’s resources in emotional, stressful, and emergency situations. • Stress initiates a complex series of events w/in the neuroendocrine system • The anterior pituitary gland secrets ACTH which stimulates the adrenal glands to secrete glucocorticoids, including cortisol. • This mobilizes the body’s energy resources, raising the level of blood sugar to provide energy. • Cortisol also has an-inflammatory effect which defends against swelling from injuries.
Physiology of Stress Response – HPA Axis HPA Axis: Hypothalamus / Pituitary Gland / Adrenal Axis
Physiology of Stress Response – SAM response • Activation of th edarenal medulla results in secretion of catecholamines (NE & E) • E is produced exclusively in the adrenal medulla & is used as an index of stress • The amount of E secreted can be determined by assaying a person‘s urine
Physiology of Stress Response – SAM response SAM = Sympatho-adrenal-medullary • Stress • ANS stimulates Posterior hypothalamus • Hypothalamus has direct neural connections to Adrenalmedula • Adrenal medulla secretes NE & E • Energy resourses mobilized • Increasing heart rate • Decreased digestion
An understanding of the physiology of stress does not completely clarify the meaning of the stress • So, we have several models that have been constructed to better define & explain stress
Theories of stress • Stress has no simple definition • It has been defined in 3 different ways • As a stimulus • ‘I have a high-stress job’ • As a response • ‘my heart races when I feel a lot of stress’ • As an interaction • ‘I feel stressed when I have to make financial decisions at work, but other types of decisions do not stress me.’
Theories of stress • 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 • Acute Alarm Reaction • Body prepares for fight or flight • Time of emergency • Heart pumps blood faster and with greater force • Blood pressure elevates abruptly • Lungs send more oxygen to muscles • Faster blood clotting • Widening of the pupils to admit more light in order to heighten visual acuity and awareness • Increase in breathing rate • Endorphins released – decrease in body’s sensitivity to pain • Elevated blood sugar levels
Definitions • Stressor- a stimulus with the potential for triggering Fight or Flight in four categories (Social, Environmental, Psychological, Philosophical) • Stress reactivity-Body changes to meet demands (F or F response) • Strains-Outcomes of stress reactivity and may be physical, psychological, or behavioral. (tension headache, phobias, addictions) • Stress- The wear and tear on the body when there is reactivity. Combination of a stressor, stress reactivity, and strain. • Homeostasis- The body’s balanced state • Eustress- Good stress • Distress- Bad Stress • Duration/Degree- • Duration= the amount of time our body’s physiology varies • Degree=Condition or the amount of physiological variance
Types of stress Stress and resource loss Stress will result when there is actual or threatened loss of resources, or a lack of gain after investing resources (Hobfoll 1989). • Acute stress • Natural catastrophes symptoms: • Panic • Phobias • Survivor guilt • Isolation, withdrawal, etc. • Examination stress impairs: • Memory • Attention • Chronic stress • Job features associated with • occupational stress: • Demand • Controllability and perceived self-efficacy • Predictability • Ambiguity • Lack of support • Chronic illness • War
Hans Selye’s view of stress • Studied the effects of long-term (chronic) stress • Concept of stress & how body defends itself in a stressful situation • 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
Hans Selye’s view of stress • In the alarm reaction, resources are quickly mobilized as th SNS springs into action • If the stressor remains, the organism enters a defensive resistance stage • Following prolonged exposure to a stressor, the energy necessary for adaptive resistance may become depleted in a stage of exhaustion
Hans Selye’s view of stress • Prolonged resistance to stress may lead to ‘disease of adaptation’ • Adrenal tumors • Vascular lesions • Gastrointestinal erosions • Rheumatism • Arthiritis • Peptic ulcer • Ulcerative colitis • Hypertension • CV disease • Hyperthyroidism • Bronchial asthma • Various psychosomatic disorders • Depressed immune system, etc.
Critics of Hans Selye’s view of stress • Theory is influencial in the learning & measuring stress • But ignores psychological factors • Experiences are mostly on non-humans
Lazarus’s view • Interpretation of stressful event is more important than the event itself • Perception includes • Potential harms • Threats • Challenges • Individuals’ perceived ability to cope w/ them • Transactional / interactionist approach • Stress as a transaction • Stress refers to a r/ship btw person & environment • Stress is a subjective experience! • Stress is a result of an interaction between • an individual’s characteristics and appraisals, • the external or internal event (stressor) environment • the internal or external resources that a person has available to them • Motivational and cognitive variables are considered central
Lazarus’s view Appraisal processes Primary appraisal processes Person considers quality and nature of a stimulus event: «How does this stressor affect my wellbeing?» • those that pose harm(potential damage that has already been done. E.g. illness or injury) • those that threaten(anticipation of harm) • those that set a challenge(the person’s confidence in overcoming difficult demands) Secondary appraisal processes Assessment of one’s resources and abilities to cope with the stressor (coping potential): «Will I be able to cope w/ this stressor?» • internal resources (e.g. determination, knowledge, strength) • external (e.g. social support, money) Reappraisal processes «What changes in coping do I need to make based on new information?» • Appraisals changes as new information becomes available • Does not always result in more stress, sometimes it decreases stress
Transactional model of stress Figure 11.1 Lazarus’s early transactional model of stress Source: adapted from Lovallo (1997: 77).
What factors influence appraisal? There are many aspects of the stimuli event itself which can influence the appraisals that a person makes. • Events that are imminent(e.g. medical results due the next day; driving test that day). • Events at an unexpected timein life (e.g. being widowed in one’s 40’s). • Events that are unpredictablein nature (e.g. being made redundant). • Events that are ambiguousin terms of: • personal role (e.g. starting a new job) • potential risk or harm involved (e.g. undergoing surgery) • Events that are undesirable(e.g. moving house due to job loss). • Events over which the individual perceives no control(behavioural or cognitive, e.g. noisy neighbours). • Events that elicit high amounts of life change(e.g. childbirth).
Lazarus’s view • Appraisals illustrated Consider forthcoming examinations as a potential stressor: • There is no way I can possibly deal with this, I simply know I will fail (threat + no resources = stress) • This will be really hard, I just am not as clever as the other students (threat + limited internal resources = stress) • Maybe I can manage this, if I revise really hard (challenge + possible internal resources = less stress) • I could perhaps do it if I get some help from my friends (challenge + external resources = less stress) • This isn’t a problem, I know the material really well (benign, nostress) • I managed to pass the last time, I’ll be okay this time (benign, no stress)
Lazarus’s view • Development of primary appraisals (Lazarus 1991; Smith and Lazarus 1993) • Motivational relevance: i.e. extent event is relevant to goals • Motivational congruence: i.e. extent situation is congruent with goals • Ego involvement: i.e. appraisals of threat to self-esteem/moral code • elicit anger, guilt, anxiety Cognitive appraisals of harm, threat and challenge were attached to emotion types, e.g. Table 11.2 Appraisal-related emotions
Lazarus’s view Development of secondary appraisals (Smith and Lazarus 1993) • Internal/external accountability (‘blame/credit’):attributing responsibility for the event. Distinguishes between anger (other-blame) and guilt (self-blame) emotions. Credit may associate with pride. • Problem-focused coping potential*:the extent to which the situation is perceived as changeable by instrumental (practical, problem-focused) coping options. If not, fear and anxiety may result. • Emotion-focused coping potential*:perceiving an ability to cope emotionally with the situation. If not, fear, sadness and anxiety may result. • Future expectancy concerning situational change:perceived possibilities of the situation being changeable. Perceived unchangeability may cause sadness. * Lazarus merged 1 and 2, referring simply to ‘coping potential’.
Lazarus’s view • Vulnerability • Stress is more likely to be aroused when a person is vulnerable • When s/he lacks of resources in a situation of some personal importance • Resources may be physical or social, but their importance is determined by psychological factors such as perception & evaluation of the situation • Vulnerability differs from threat in that represents only the potential threats • Threat exists when one perceives that his or her self-esteem in jeopardy • Vulnerability exists when the lack of resources creates a potentially threatening or harmful situation
Lazarus’s view Stress and coping • five main coping functions, each of which contribute to successful adaptation to a stressor: • reducing harmful external conditions; • tolerating or adjusting to negative events; • maintaining a positive self-image; • maintaining emotional equilibrium and decreasing emotional stress; • maintaining a satisfactory relationship with the environment or with others.
Lazarus’s view • Coping is a dynamic process involving a constellation of cognitions and behaviour that arise from the primary and secondary appraisals of events, and the emotions attached to them. • Anything a person does to reduce the impact of a perceived or actual stressor • Operate to alter or reduce negative emotion(s) attached to the stressor, or it can directly target the stressor • May or may not succeed, but it is concerned with trying to achieve adaptation
Coping taxonomies Table 12.1 Coping dimensions
Other Influential Researchers • Simeons • Psychosomatic disease • Benson • Relaxation response • Vogt • Autogenic training • Jacobson • Progressive relaxation • Several theories explain the causes of stress: • Holmes and Rahe- Life events theory: stress occurs when the situation requires more resources than are available • Kobasa and colleagues- Hardiness theory: one’s attitude toward the events determines stress, not the event. • Social support theory: insufficient social support for responding to event
Sources of stress • Cataclysmic events w/ natural or human causes • “sudden, unique, and powerful single life-events requiringmajor adaptive responses from population groups sharing the experience” by lazarus • natural disasters • posttraumatic stress disorder • physical proximity to the event • time elapsed since the event • the intention of the perpetrators • Changes in an individual’s life history • major & minor life events both are stressful • the importance of change • life events usually evolve more slowly than cataclysmic events • Ongoing hassles of daily life • unlike life events that call for people to make adjustmentsin their lives, daily hassles are part of everyday life • can originate from both thephysical and the psychosocial environment
Sources of stress • Family Relationships • Work, Money, Sexuality • Having A Family Member w/ Chronic Disease • Workplace Demands • Discrimination & stigmatization • lack of control, status, and compensation • Lower-level occupations are actually more stressful than executive jobs • Middle-level managers such as foremen and supervisorsalso have highly stressful jobs • Multiple Roles • Community Conditions • Urban press • the environment of poverty • Pollution, noise, violence • Crowding • Population density as a physical condition inwhich a large population occupies a limited space • Crowdingis a psychological condition thatarises from a person’s perception of the high-densityenvironment in which that person is confined
Measurement of stress • First measure stress in order to understand the effect of stress on disease • Methods of measurement • Two broad categories: • Physiological measures • Associated w/ the view that stress is a response • focus is on the biology of stress • Self-reports • Often used by health psychologists who tend to take a tranactional view of stress • Either life events or daily hassles
Measurement of stress 1. Physiological measures • Physiological indexes • Blood pressure • Heart rate • Galvanic skinresponse • Respiration rate • Increasedsecretion ofstress hormones such as cortisol and epinephrine • The activation of the body’s sympatheticnervous system and HPA axis • Epinephrine and norepinephrine can be measured in blood orurine samples and can provide an index of stress • Physiological measures of stress is that they are direct, highly reliable, and easily quantified • The mechanical and electrical hardware,and clinical settings that are frequentlyused may themselves produce stress
Measurement of stress • Self-reports • Life events scale • The earliest and best known of these self-report procedures is theSocial Readjustment Rating Scale byHolmes &Rahe in 1967 • a list of 43 life events arranged in rankorder from most to least stressful • the previous 6 to 24 months • scores can be correlated with future eventssuch as incidence of illness • The Life Events Scale for Students (Clements & Turpin, 1996) • The Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1983) • assesses three components of stress • daily hassles • major events • changes in coping resources • Everyday Hassles Scales by Lazarus • Daily hassles are “experiences and conditions of dailyliving that have been appraised as salient and harmfulor threatening to the endorser’s well-being” • Inventories must be both reliable and valid to predict future stress-related illness
Stressful life events Representative life event items from the social readjustment rating scale and their LCUsSource: Holmes and Rahe (1967).
Coping with stress • Personal Resources • Health & energy • Positive belief • Problem solving skills • Material sources • Social skills • Social support • Social support refers to a variety ofmaterial and emotional supports a person receives from others • Social contacts / network refer to the number and types of people w/ whom one associates • Social isolation, which refers to an absence of specific, meaningful interpersonal relations • Stress-buffering hypothesis • Personal control • confidence that they have some control over the events that shape their lives • Locus of control • Coping strategies