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Noise/Community Stress. Dana Malka, Sarah McCardell, Jingsha Wu. Stress: (Evans & Cohen). A process that occurs when there is an imbalance between environmental demands and response capabilities of the organism
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Noise/Community Stress Dana Malka, Sarah McCardell, Jingsha Wu
Stress:(Evans & Cohen) • A process that occurs when there is an imbalance between environmental demands and response capabilities of the organism • Individual cognitive appraisals- stress occurs when you decide that environmental stimuli are going to exceed your coping capacities
Stress- an alternative definition • A formulation that predicts that certain environmental conditions lead to a stress reaction, which may have emotional, behavioural, and physiological components
Theoretical perspectives on Stress:(Evans & Cohen) • Physiological Perspective- • emphasize physiological responses of the body to noxious stimuli • homeostatic processes- stressor disrupts internal equilibrium and organism focuses on reequilibration to return to homeostatic balance • Cannon, Selye • Psychological Perspective- • emphasize the individual’s interpretation of the meaning of environmental events plus an appraisal of personal coping resources • stress occurs when a situation is appraised as demanding with potential of exceeding coping resources
Classical Studies of Stress: • One of the earliest contributions to stress research: Walter Cannon’s (1932) description of flight or fight response • Fight usually refers to aggressive responses to stress, and flight may been seen in social withdrawal
Models of Environmental Stressors:(Evans & Cohen) • Stimulation Levels • most common explanation of effects of environmental stressors • Yerkes-Dodson Law
Models of Environmental Stressors cont’d:(Evans & Cohen) • Control • Humans have a strong need for environmental mastery and a sense of self-efficacy • Actual or perceived control over a stressor leads to fewer negative consequences than exposure to stressors that are uncontrollable • Chronic exposure to environmental stressors that are uncontrollable/unpredictable may lead to learned helplessness due to failure of coping efforts to modify an environmental source of stress
Hans Selye (1956, 1974) • Selye’s work on the General Adaptation Syndrome • When an organism confronts a stressor, it mobilizes itself for action • The response itself is nonspecific with respect to the stressor • The individual will respond with the same physiological pattern of reactions
After-effects: • Consequences of a stimulus that occur after the stimulus has stopped • Effects of a stressor on mood or behaviour, often measured by task performance, that occur after termination of the stressor • May include • cumulative fatigue (frustration tolerance/cognitive performance) • overgeneralization of learned coping responses • learned helplessness • physiological activation • chronic adaptive efforts can lead to disease • less ability to cope with subsequent stressors
Environmental Stressors:(Evans & Cohen) • Typically aversive, primarily uncontrollable, and of variable duration and periodicity and require low to moderate adjustments
Cataclysmic Events(Lazarus & Cohen, 1977) • Sudden catastrophes that demand major adaptive responses from all individuals directly affected by the event • Usually affects whole communities of people
Example: Toxic Exposure • The belief that one has been exposed to toxic substances may cause a stress reaction • In two studies of two toxic accidents perceived threat to health was associated with stress
Example: Natural Disasters • Disaster victims are more likely to exhibit symptoms of stress and emotional problems shortly after a disaster • medically unexplained physical symptoms • depression • nightmares • Post Traumatic Stress Disorder (PTSD) • Hurricane Katrina Survivors
Stressful life events(Lazarus & Cohen, 1977) • Major incidents in the lives of people that typically require personal or social adaptive responses • Clearly defined time referents • Social Readjustment Rating Scale • According to the scale, how stressed are you?
Daily Hassles(Lazarus & Cohen, 1977) • Typical events of ordinary life that may cause frustration, tension, or irritation
Ambient Stressors (Lazarus & Cohen, 1977) • Continuous, relatively stable, and intractable conditions of the physical environment • Many are background conditions, usually unnoticed unless they interfere with some goal or health
Ambient Stressor: Noise • Important characteristics are predictability of noise bursts and degree of personal control over noise • Sources of noise include occupational exposures, transportation sources, activities of nearby residences • loud unpredictable noise exposure has physiological responses • interferes with task performance • can influence memory • interferes with decision making • influences affect and interpersonal behaviours • stress, tension, annoyance, altruistic behaviour
Effect of High Intensity Noise on Non-Auditory Processes (Cohen et al 1982): • Narrowed focus attention • Reduction in one’s perception of control over environment • Alteration of physiological arousal characteristic of generalized stress reaction
Previous Research Findings (Cohen et al): • Higher absenteeism and accident rates From: European Foundation for the Improvement of Living and Working Conditions
Knipschild (1977) Residents (especially woman) were more likely to be under medical treatment Noisy & quiet areas differ in socioeconomic status Increase in the purchase of cardiovascular drugs vs. number of aircraft over-flights at night. Heft (1979) Poor performance in matching and incidental memory task
Los Angeles Noise Project Overview • Children living and attending school in the air corridor of Los Angeles International airport vs. children from school in quieter neighbourhoods • Test 1: cross-sectional study • Measures the course of adaptation and impact of noise abatement intervention on blood pressure, attentional processes and the feeling of personal control • Retest after one year to determine whether effects of noise occurred in test 1would persist after children were assigned to quieter classrooms
Aircraft Noise & Blood Pressure • Test 1 data: higher systolic and diastolic pressure • Replication of study found higher blood pressure among those exposed 2 years or less and not among those attending school for a longer period of time
Aircraft Noise & Helplessness • (Seligman, 1975) Learned helplessness • Measures of helplessness: whether or not puzzle was solved, time to solution, whether child given up before allotted time • Test 1: task 1 - insoluble (failure) vs. soluble puzzle task 2 - same puzzle for both groups • self-selected into a failure condition • children from noise schools were • more likely to fail and give up solving the puzzle • Longer the exposure to noise, the slower s/he solve the puzzle • less capable of performing cognitive task • Test 2: Noise school children were reliably more likely to fail the test puzzle and more likely to take longer solving it than quiet school children
Aircraft Noise, Distractibility & School Achievement • Test 1: % of E found was the criterion measure for performance • distracting vs. ambient sound condition • noise schools children performed better on distraction task during the first 2 years of exposure and perform worst after 4 years of exposure • Length of noise exposure increase, children more disturbed by auditory distracters • Study result found that math, reading, and auditory discrimination were all unrelated to noise or duration of noise exposure
Noise Abatement & Noise-stress Reduction • impact of abatement intervention • slight improvement on marginal effect of increasing number of children who were able to solve moderately difficult test puzzle and that math achievement was higher for children in abate condition • Individual differences • What noise abatement intervention can be implemented in noise impacted areas?
Motivational Consequences of Environmental Stress: (Evans & Stecker, 2004) 3 research paradigms- • Uncontrollable stressor is used to induce helplessness • Look at how stressor exposure increase vulnerability to the induction of learned helplessness by other uncontrollable stimuli • Behavioural after-effects paradigm
1.Helplessness induction and Stress • Hiroto (1974) - escapable vs. inescapable stimuli • Characteristics of people more susceptible to helplessness: • High need for control • External locus of control • Type-A personality • Attributional styles that blame negative events on stable, internal characteristics • Intolerance of high levels of environmental stimuli • Baum & Valins (1977) - crowding in college dormitories
Example: Personality Types and Stress • Kirkcaldy, Shephard, Furnham (2002) studied 332 managerial staff throughout Germany • Those with Type A personality and external locus of control associated with greater levels of perceived stress, lower job satisfaction, poorer physical and mental health
2. Environmental Stressors & Vulnerability to Helplessness Induction • Rodin (1976)- residential crowding • Maxwell & Evans (2000)- daycare noise level vs. longer time to solve puzzle
3. Stressor & Task Persistence • Behavioural aftereffects measure (i.e. proofreading, stroop performance, puzzle) • Glass & Singer (1972) - unpredictable or unsignalled noise and perceived control • Mackintosh et al.(1975) – stroop task: men and women revelled opposite patterns • Fleming (1987) high-density vs. low-density neighbourhoods • Klein & Beith (1985) persistence on unsolvable puzzle increased following noise exposure. People seem to give up on the puzzle because they know that the puzzle is unsolvable
Additional Studies:Bronzaft and McCarthy (1975) • Tested reading scores of students from 2nd to 6th grade • Researchers found students in building closer to subway track performed more poorly on reading task than students on opposite side of building
Evans, Bullinger, Hygge (1998) • Studied children ages 9 to 11 over a 2 year period before and after inauguration of the Munich International Airport • Measured cortisol, epinephrine, nor epinephrine, and blood pressure through urine and blood tests • Epinephrine, nor epinephrine, and blood pressure increase in children living in the flight paths of the new airport after it opened
Stansfield et al. (2005) • 2844 children from 89 schools in the UK, Spain, and the Netherlands participated • Exposure to chronic aircraft noise was associated with a significant impairment in reading comprehension • Also associated with significant impairment with regards to memory and recognition • Researchers noted no effects of either aircraft noise or road traffic noise on self reported health or mental health
Adaptation and Coping: • Habituation- • In most situations, when an aversive stimulus is presented many times, the stress reaction to it becomes weaker and weaker • Adaptation to a stressor may occur because neurophysiological sensitivity to the stimulus becomes weaker, uncertainty about the stressor is reduced, or the stressor is cognitively appraised as less and less threatening