Units 14-16: Health Psychology Unit 14: Health Psychology - Stress

Health Psychology n Health psychology examines the relationship between psychological behavior and physical health/illness. n Focus of health psychology is on –Wellness –Prevention of illness n Many major causes of death are related to behavior and lifestyle rather than to infections. –Smoking, drinking, risky sex are causes of death that can be prevented. –These behaviors can be understood in psychological terms

Biopsychosocial model of health

Stress

WHAT IS STRESS? l Stress is your mind and body’s response or reaction to a real or imagined threat, event or change. l The threat, event or change are commonly called stressors. Stressors can be internal (thoughts, beliefs, attitudes) or external (loss, tragedy, change).

Stressors - vocab n Acute Stressors –Sudden and brief –We evolved to deal well with these n Chronic Stressors –Last for a long time and/or recur –These are the ones that cause us health issues n Allostasis: balance between the body’s systems

Stressful Life Events  Catastrophic Events  earthquakes, combat stress, floods  Life Changes  death of a loved one, divorce, loss of job, promotion  Daily Hassles  rush hour traffic, long lines, job stress, burnout

Social Readjustment Rating Scale – Holmes and Rahe (1967) nAn attempt to quantify and compare stressful life changes nScores are calculated for a person’s experiences over the past year. nHigh life change scores (300+) are related to relatively high frequency of illness, accidents and athletic injuries.

Evaluation of SRRS n Does not take into account some people find some things stressful whilst others do not. n No cause and effect relationship show; we cannot give reliable predictions about risks of stress-related illness based on this scale.

Stressful Life Events  Chronic Stress by Age

General Adaptation Syndrome Selye (1936) Physiological aspects of stress

Stress and Illness  General Adaptation Syndrome  Selye’s concept of the body’s adaptive response to stress in three stages Stress resistance Phase 1 Alarm reaction (mobilize resources) Phase 2 Resistance (cope with stressor) Phase 3 Exhaustion (reserves depleted) The body’s resistance to stress can last only so long before exhaustion sets in Stressor occurs

Effects of Stress n The sympathetic portion of the autonomic nervous system is activated during stress. –Goal is to increase muscle strength & endurance, slow or halt all other processes –Increased heart rate, muscle tension,blood pressure –Release of epinephrine, cortisol and others –Body neglects other necessary functions (immune response, healing, reproduction)

Pituitary hormone in the bloodstream stimulates the outer part of the adrenal gland to release the stress hormone cortisol Sympathetic nervous system releases the stress hormones epinephrine and norepinephrine from nerve endings in the inner part of the adrenal glands Thalamus Hypothalamus Pituitary gland Adrenal glands Cerebral cortex (perceives stressor )

Stress and health (cont’d) n Immune system functioning is impaired by exposure to stress. –Cortisol suppresses immune system functioning (T-cells). –Compromised immune system is less able to resist infection and cancer development. n Cardiovascular Health –Increased heart rate and blood pressure lead to a hardening of the veins –Cardiac arrest can result

Stress and Disease  Negative emotions and health-related consequences Unhealthy behaviors (smoking, drinking, poor nutrition and sleep) Persistent stressors and negative emotions Release of stress hormones Heart disease Immune suppression Autonomic nervous system effects (headaches, hypertension)

Stress and Illness  Leading causes of death in the US in 1900 and 2000

Direct effect on health n Cohen et al (1991) 394 healthy participants were asked to complete a questionnaire assessing stress levels and then exposed to 1 of 5 respiratory viruses n Those experiencing most stress were most likely to develop colds. n This was a direct effect because there was no other variable.

Kiecolt-Glaser (1984) n Study exam stress on students n Took blood samples from 75 1 st yr med students one month before exam and on first exam day. n Students also completed stress surveys n Second sample had significantly fewer T-cells (showing reduced immune response) n Students whose surveys showed they were stressed and lonely had lower T-cell counts

Stress and the Heart Hopelessness scores Heart attack Death Low riskModerate riskHigh risk Men who feel extreme hopelessness are at greater risk for heart attacks and early death