Week 5: Stress Flashcards
What is stress?
A NEGATIVE EMOTIONAL EXPERIENCE
Accompanied by predictable biochemical, physiological, cognitive and behavioural CHANGES
Directed at ALTERING stressful event
Or ACCOMMODATING to its effects
How does stress arise?
Primary appraisal > Labelling: What is this event? > Harm, threat, challenge?
+
Secondary appraisal > Can I respond to it? > Available and sufficient resources?
What are the models of stress?
- Fight-or-flight
- Selye’s general adaptation syndrome
- Tend-and-befriend
- Challenge vs. threat
What is fight-or-flight?
Walter Cannon (1932):
- When threat is perceived, body experiences AROUSAL via the activation of the SNS and endocrine system
- Which mobilises the organism to action
What is fight? What is flight?
Fight = aggressive response, flight = withdrawal
Is fight-or-flight good for us?
Adaptive b/c it helps org. to respond quickly
But repeated or unabated activation & arousal = health problems
What is Selye’s general adaptation syndrome?
Hans Selye (1956):
- All stressors elicit the same pattern of physiological changes.
- REPEATED or PROLONGED EXP. of these changes will exert wear and tear on system
What are the 3 stages of stress based on Selye’s general adaptation syndrome?
1) Alarm: Mobilised to meet the threat
2) Resistance: Tries to confront and/or cope with threat
3) Exhaustion: Depletion of physio. resources when efforts to overcome threat fail/succeeed
What are the criticisms of Selye’s general adaptation syndrome?
1) Assumes all stress lead to the SAME LEVEL of physio response; does not consider the role of appraisals (ignores indiv. diffs. in stress reactivity)
2) Assumes all stressors produce the SAME KINDS of biological responses; does not consider role of personality, emotions and biological constitutions (e.g. emotions - positive emotions also produce same kind of bio. response)
3) Unclear about what is most implicated in exp. of stress - exhaustion or chronic activation (resistance)?
4) Stress can occur before and persist after the duration of the stressor; it is not limited to the three phases – A) Stress may peak at another stage, B) Some ppl’s stress response do not decrease, actually remain sustained/persist after stressor
What is tend-and-befriend?
Taylor et al. (2000):
- Ppl and animals can respond to stress with SOCIAL AFFLIATION and NURTURANT BEHAVIOUR toward offspring, particularly for females
What is the concept behind tend-and-befriend?
Arises due to gender diffs. in adaptive challenges
Men = Hunting & protection roles = Fight/flight response Women = Foraging & child care roles = Tend & befriend
What is the key underlying biological mechanism of the tend-and-befriend model?
Oxytocin (stress hormone)
- Increases affiliative behaviours and calmness
- Particularly infl. by estrogen (–> females)
What is the limitation of the tend-and-befriend model?
Assumes that it is a female-exclusive response
What is the challenge vs. threat model?
Secondary appraisals of stressors can alter the experience and response to stressors
How does one determine whether a situation is a challenge or a threat?
Blascovich & Tomaka (1996):
- Secondary appraisals depend on the assessment or situational demands vs. personal resources
- PR > Sit. demands = Challenge, approach
- PR < Sit. demands = Threat, withdraw
How does challenge/threat appraisals affect cardiovascular profiles?
Challenge states: Short PEP, high CO, low TPR
Threat states: Short/long PEP, low CO, high TPR
What are the pathways to poor health due to stress?
1) Direct physiological effects
- E.g. elevated BP
2) Health behaviour changes
- E.g. increased smoking
3) Psychosocial resources
- E.g. threatened social support
4) Healthcare
- E.g. decreased adherence to treatment
What is the physiology of stress?
Sympathetic-Adreno-Medullary (SAM) system
- SNS
- Endocrine system
Hypothalamic-Pituitary-Adrenal (HPA) axis
- CNS
- Endocrine system
Primary & secondary appraisals of stressors are first performed by the cerebral cortex which then set off these responses
What is the process of activation of SAM system?
- Event appraised as stressful -> Brain sends info to HYPOTHALAMUS to activate SNS
- SNS activation -> Stimulates ADRENAL MEDULLA -> Secrete catecholamines
What are the effects of activation of SAM system on chronically stressed individuals?
- Suppressed immune system due to excessive release of EP and NE
- Higher risk of CVD due to overactive SNS
What is the process of activation of HPA axis?
- Event appraised as stressful -> HYPOTHALAMUS stimulates PITUITARY GLAND -> Secrete ADRENOCORTICOTROPIC HORMONE (ACTH)
- ACTH -> Stimulates ADRENAL CORTEX -> Release glucocorticoids, esp. CORTISOL
What are the effects of activation of HPA on chronically stressed individuals?
- Generally heightened cortisol levels (esp. awakening cortisol)
- Exaggerated cortisol reactivity, and slow recovery
What are the other considerations for the physiology of stress?
1) Reactivity
2) Recovery
3) Allostatic load
What is reactivity?
Degree of change (from baseline or average) that occurs in autonomic, neuroendocrine, and/or immune responses due to stress
Affected by genetic make-up, personality or early life exp
What is recovery?
How quickly an individual returns to baseline or average after a stress response
Affected by genes, personality or past exps too
What is allostatic load?
Physiological costs of chronic exposure and exp. of stress, i.e. “wear and tear” of the system
**Dimensions of stress: The obvious
What makes an event stressful?
- Negative events
- Uncontrollable and/or unpredictable events
- Ambiguous events
- Overload
**What is a factor that can mitigate the effects of uncontrollable and/or unpredictable events?
Feelings of control
- Can mitigate subjective experience of stress, biochemical reactions to it (i.e. higher catecholamine levels and lower immune responses)
**What are the less obvious dimensions of stress?
- Perceived stress vs. objective stress
- Adaptation to a permanent stressor
- Pre-stress vs. ongoing stress vs. post stress
How does perceived stress and objective stress differ?
Perceived stress and objective stress independently predicted negative moods and health complaints of air traffic controllers
Air traffic controllers who reported they were not stressed under objectively stressful conditions still showed behavioural patterns of stress
How does adaptation to a permanent stressor work?
Most ppl can adapt to moderate and predictable stressors
But vulnerable or at-risk groups (e,g, children, elderly, low SES) may find it difficult to adapt given their inherent lack of resources (e.g. cognitive, material) and perceived control
How does pre-stress vs. ongoing stress vs. post-stress differ?
Pre-stress and post-stress can be as stressful as ongoing stress
What are some types of acute stress inductions used in the study of stress?
- Trier Social Stress Task (TSST)
- Cold Pressor Test (CPT)
What is the Trier Social Stress Task?
- Two tasks: Speech and mental arithmetic tasks performed in front of an evaluative audience
- Cardiovascular responses (e.g. HR, cardiac efficiency, BP) and endocrine responses (e.g. salivary cortisol) are measured continuously throughout the tasks
What is the usefulness of the TSST?
Highly reliable in inducing stress in the lab for the average indiv.
Also for identifying indivs. who are highly reactive to stress
What is the Cold Pressor Test?
- Immerse hand or foot in a cold water bath, maintained at a temperature of 1 to 5 degrees Celsius
- Specifically activates the sympathetic and parasympathetic response
- Cardiovascular responses (e.g. HR, cardiac efficiency, BP) measured during CPT
How does the TSST and the CPT differ in inducing stress?
TSST - Induces social evaluative stress
vs.
CPT - Induces orthostatic stress (i.e. physical stress)
How does inducing disease work in the study of stress?
Effects of stress can be studied by exposing ppl to viruses and then assessing whether they get ill
What is the Common Cold Project?
- Measured stress levels in adult Ps
- Infected the with viruses linked to the flu/common cold, and had them quarantined
- Onset of flu or the common cold are typically associated with higher stress
- This association can also differ by other factors, such as social support, sleep quality
How are stressful life events involved in the study of stress?
- A person’s life course involves responding and adjusting to the changing environment, which is often accompanied by increase in stress levels
What is the Social Readjustment Rating Scale (SRRS)? What are its limitations?
An inventory of 43 stressful life events
Only predicts health and illness modestly
- Vague items
- Preassigned scores do not take into acc. indiv. diffs.
- Some events are positive and controllable
- Does not assess whether the stress events were successfully resolved
What is the Perceived Stress Scale (PSS)?
Developed to address the problem of variability and subjectivity in the experience and reports of stress
Predicts general health and illness better than SRRS
How does daily stress relate to the study of stress?
Cumulative minor stressors can wear a person down, or aggravate/worsen experiences of ongoing chronic or major stressors
- Measure of daily hassles
- Experience sampling
- Tracking moment to moment or daily events (and sometimes physiology)
What are the effects of workplace stress (chronic stress)?
Can lead to burnout or karoshi (death from overwork)
What are the sources of workplace stress?
- Desk-bound jobs
- Jobs that require extreme physical exertion or sleep deprivation
- Overload
- Ambiguity and role conflict
- Lack of control at work
- Job uncertainty; threat of unemployment
What is caregiver stress?
With people living longer and a higher incidence of chronic illnesses, indivs. tasked with caring for family members with chronic illnesses are becoming depressed
What are the problems associated with caregiver stress?
- Caregivers may not realise they’re stressed, or ignore their stress b/c they believe it is their duty to care for their family member
- When driven to desperation, caregivers may act out on their family members
- May also extend to professional caregivers (eg. nurses) –> high job turnover rate
