Physiological Psychology STRESS Section 1 Stress as a bodily response Section 2 Sources of stress Section 3 Critical Issues: Stress management

What is stress? Pressures, demands (stressors), exert force on the body, stress is the body’s response to this. A stress response is an innate, defensive and adaptive reaction Stress levels also depend on whether the person feels that they can cope with demands placed on them or not SNAP ton

Major Types of Stress Frustration: blocked goal Conflict: incompatible motivations –Approach-approach –Approach-avoidance –Avoidance-avoidance Change: having to adapt –Social Readjustment Rating Scale –Life Change Units Pressure –Perform/conform

Stress Definition Stress is a state of psychological and physical tension produced when an individual perceives that they are unable to cope with the demands imposed on them by a stressor. The consequent state of tension can be adaptive (eustress) or maladaptive (distress)

Effects of stress STRESSORS Family Relations Disagreements Money Worries Need to Succeed Exams Friends Decisions New Situations FLIGHT FIGHT RETURN TO NORMAL COPING COPING STRATEGIES RELAXATION NOT COPING POSSIBLE DISEASE OR MENTAL ILLNESS EXHAUSTION POOR DIET NO EXERCISE NEGATIVE THOUGHT IRRITABILITY

Responding to Stress Emotionally Emotional Responses –Annoyance, anger, rage –Apprehension, anxiety, fear –Dejection, sadness, grief –Positive emotions Emotional response and performance –The inverted-U- hypothesis

Responding to Stress Physiologically Physiological Responses –Fight-or-flight response –Selye’s General Adaptation Syndrome Alarm Resistance Exhaustion

The Biology Of Stress PHYSIOLOGICAL AROUSAL : Walter Cannon(1932) The response to stress Stress and the nervous system Neurons Neurotransmitters

AUTONOMIC NERVOUS SYSTEM Automatically responds to stressor SympatheticParasympathetic

Sympathetic Response to Stress Hypothalamus causes: Increases arousal in the sympathetic nervous system Increased heart rate & blood pressure Constriction of peripheral blood vessels Respiration rates increase Bronchial tubes dilate Pupils dilate Digestive processes decrease Sympathetic activation prepares the body for intense motor activity

Parasympathetic response to stress Serves regenerative, growth-promoting, energy- conserving functions Its effects include the opposite of the effect of the sympathetic nervous system Functions under normal, non-stressful conditions Also activated by the hypothalamus re-establishes homeostasis in the system reconstructive process following stressful experience slows the heart rate & decreases blood pressure decreases muscle tension slows respiration neutralizes fight or flight response

ENDOCRINE SYSTEM GLANDS HORMONES

Contrasting Communication Systems NervousEndocrine  Consists of nerve cells  Acts by transmitting nerve impulses  Acts rapidly  Direct control  Specified localised effects of neurotransmitters  Short lived effects  Consists of ductless glands  Acts by releasing hormones  Acts slowly  Indirect control  Hormones spread around body  Hormones remain in blood for some time

Structure of the Endocrine System The endocrine system consists of ductless glands distributed throughout the body The neuroendocrine system is made of those endocrine glands that are controlled by the nervous system Glands of the endocrine and neuroendocrine systems secrete chemicals called hormones Hormones move into the blood stream to be carried throughout the body Specialized receptors on target tissues or organs allow hormones to have specific effects even though they circulate throughout the body

Endocrine Responses to Stress Hypothalamus causes: The pituitary gland to secrete adrenocorticotropic hormone (ACTH) that stimulates the adrenal cortex Sympathetic fibers to directly activate the adrenal medulla The adrenal glands are located on top of each kidney Each gland is composed of: –an outer covering: the adrenal cortex –an inner part: the adrenal medulla Both secrete hormones that are important in the stress response

Homeostasis The process of maintaining a reasonable constant internal environment in the body F or 37 ºC

Work together to control stress response SAM Sympathetic Adrenal Medullary System HPA -Hypothalamic -Pituitary -Adrenal - axis

Effects of SAM activity Heightened activity of SAM prepares us for Fight or Flight. Increase in energy Increased alertness Increased blood flow to the muscles Increased heart and respiration rate Reduced activity in digestive system Increased release of clotting factors in the blood Adrenaline and Noradrenaline increase the output of the heart,which can cause increase in Blood Pressure.

Adrenomedullary Response - SAM Occurs through the activation of the sympathetic- adrenal medulla (SAM) complex: Perception of stress causes the hypothalamus (via nervous connection) to activate sympathetic fibers Sympathetic fibers activate the adrenal medulla Adrenal medulla secretes the catecholamines: epinephrine & norepinephrine This causes: Increased heart rate, blood pressure, breathing rate & blood glucose levels Shuts down digestive system Rapid, short-lived response to stress

Adrenocortical Response - HPA Occurs through the activation of the hypothalamus-pituitary-adrenal (HPA) cortex complex: Perception of stress causes the hypothalamus to release ACTH releasing hormone This causes the anterior pituitary to secrete ACTH ACTH stimulates the adrenal cortex to secrete glucocorticoids and mineralocorticoids Glucocorticoids Protein and fat get metabolized into glucose Reduce inflammation, suppress immune cells Mineralocorticoids Blood volume and pressure increase

Sympathetic and Endocrine Responses to Stress Stress perception causes a chain reaction: SAM rapid, short-term stress reaction the sympathetic NS stimulates the adrenal medulla the adrenal medulla produces epinephrine and norepinephrine HPA slower but longer-lasting response the pituitary releases ACTH ACTH causes the adrenal cortex to release glucocorticoids and mineralocorticoids

Effects of HPA activity + Cortisol is important for coping with long term stress,it maintains a steady supply of fuel. +Glucocorticoids conserve glucos for neural tissues, elevate or stabilise blood glucose levels,mobilise protein reserves, conserve salts and water. +Cortisol helps reverse bodies initial stress responses and helps body to revert to a stable state.

Effects of HPA activity -The blood has elevated levels of glucose (for energy) and hormones (ACTH and adrenaline) so the body continues to use its resources fast. -The anti inflammatory action of glucocorticoids slows wound healing -Glucocorticoids suppress the immune system which protects the body against viruses and bacteria.(so we are more likely to pick up infection.)

General Adaptation Syndrome G. A. S Hans Selye(1936) - ‘STRESS’ research PIONEER Rats showed same symptoms in response to all of Stimuli. General state of ‘stress’

The General Adaptation Syndrome (1) Defined by Selye in Comprises 3 stages: Stage I: Alarm The body’s defences against stressors are mobilized through activation of the sympathetic nervous system Activation of the SAM complex Arousal of the sympathetic nervous system releases hormones (adrenaline) that help prepare the body to meet stress and danger Highly adaptive short term response to an emergency situation

The General Adaptation Syndrome (2) Stage II: Resistance The body enters this stage if the stress is prolonged Activation of the HPA complex Arousal is lower But the body continues to draw on internal resources at an above normal rate Outwards appearance seems normal Physiologically, the body’s internal functioning is not normal Sets the stage for diseases of adaptation (e.g., peptic ulcers, ulcerative colitis)

The General Adaptation Syndrome (3) Stage III: Exhaustion Continued exposure to the same stressor drains the body further The capacity to resist is depleted Illness results This stage is characterized by activation of the parasympathetic division of the ANS But at an abnormally low level In severe cases, results in death

STAGE 1. ALARM: STAGE 2. RESISTANCE STAGE 3. EXHAUSTION

Evaluation of GAS + Pioneering research into stress + Alerted medicine to the importance of stress in disease - Not much attention paid to SAM, the relationship between SAM and HPA not fully appreciated -Stress does not always produce the same physiological patterns. Mason (1975)different patterns of adrenaline/noradrenaline and cortisol for different stressors. -Criticised for use of non human animals -Suggestion that people respond in a passive way to stress. Mason.

How does stress cause physical illness? DIRECTLYINDIRECTLY SUPPRESSING THE IMMUNE SYSTEM Leucocytes (white blood cells) Lymphocytes (B Cells or T Cells) Anti bodies Natural killer cells Endorphins CARDIOVASCULAR DISORDERS Hypertension CHD Strokes Changes in health practices that will increase risk of illness  Smoking  Drinking rugs  Sleeplessness  Exercise less

Brain Response to Stress Limbic System Adds an element of emotion to the experience of stress Usually negative emotions: fear, anger, anxiety, pain Reticular formation Communication network that filters messages to the body Receives input from all the sensory systems and determines which sensory information is processed or blocked This allows us to selectively attend to specific tasks while ignoring irrelevant information

What sorts of illness does stress cause? Ulcers Brady CHD Friedman & Rosenman Hypertension Cobb & Rose Monkey Business Man Air Traffic Controller

Sources of Stress Lesson objectives: Identifying sources of stress Theory-Assessing own stress levels using SRRS, a way of identifying a link with life events, sources of stress and illness. Evidence for SRRS Evaluating this approach Checking knowledge.

SOURCES OF STRESS Transactional Model Cox (1978)

LIFE EVENTS as stressors Social Readjustment Rating Scale Holmes and Rahe Key Study : Rahe et al stress of life events Correlation stress related illness

De Longis et al DAILY HASSLES & UPLIFTS e.g. rising prices home maintenance crime physical appearance (bad hair day?) weight recreation relations with friends / family good weather job promotion

Work Place Stress Pressures of workWork environment Key Study : Marmot et al ‘Workplace Stressors’ BURNOUT

NOISE (Glass et al) PredictabilityControllability Higher Stress? ControlLack of Control Langer and Rodin ‘Old Peoples Homes’

Individual Differences Can be innate or learned Weg Anderson Cooper et al Bailey & Dua Personality – Friedman & Rosenman Gender Culture Hardiness - Kobasa Taylor Franken Houser Hastrup et al Ogden Gyton & Hall

STRESS ! Critical Issue STRESS MANAGEMENT

Coping (1) Lazarus and Folkman (1984) Constantly changing cognitive and behavioural efforts to manage specific internal and/or external demands that are appraised as taxing or exceeding the resources of the person Several important elements of the definition: Coping is a process of constant evaluation of the success of one’s strategies Coping is learned as one encounters situations Coping requires effort Coping is an effort to manage. Success is not contingent on mastery, just good enough

Coping (2) Health & energy Positive belief the ability to cope is enhanced when people believe they can successfully bring about desired consequences Problem-solving skills having specific knowledge or abilities related to specific problem Social skill ability to get other people to cooperate Social support feeling of being accepted, loved, or prized by others Material Resources

Coping (3) Problem Focussed Coping consists of changing the situation redefining the problem looking at alternative solutions evaluating the implications of the alternatives choosing the best one to act on Emotion-focussed coping consists of controlling and possibly changing the emotional response to an event cognitive responses such as avoidance or minimization the goal is to decrease emotional distress often used when the individual feels that nothing can be done about the situation