13 June 2012

Stress: appraisal, coping, and physiology

Notes from the first few weeks of a class on stress by Sally Dickerson taught throughout Spring 2012.

Basics

Eustress = positive/healthy stress. Example: wedding, vacation. As opposed to distress. Three phases of stress: stressor, appraisal, and response.

The stressor is the eliciting event; examples are being stuck in traffic, having an exam, or arguing with your partner. Stressors break homeostasis, our stability with the environment. A stressor can be acute or chronic. Durations of exposure to stressor vs duration of perceived threat vs duration of stress response.

The response happens at all levels: emotional (e.g. fear), physiological (e.g. BP increases), and behavioral (e.g. running away). The response aims at bringing back homeostasis. If it lasts for too long, sickness appears because of the general adaptation syndrome.

Appraisal

Evaluation/interpretation of the harm, threat, and overwhelmingness of the stressor to determine the response. Individual- and context-specific. Individuals who are told beforehand that "pain is going to happen" have stronger physiological response to a stressor than individuals told "it's just a formality, nothing too big". Appraisal consists of the primary appraisal and coping.

Primary appraisal

The individual estimates the importance/meaning of the stressor, and its implications on her well-being. "This is the most important day of my life" vs "No big deal". Three types of primary appraisals:

Type Description Emotions generated Physiological response Example with stressor = "just got fired"
Harm/loss The damage has already been done sadness, anger damaging "Everyone looked at me packing my stuff"
Threat Possibility of future damage anxiety, fear damaging "How am I going to pay the rent?"
Challenge Potential to overcome and profit. excitement positive/healthy,
smaller than harm or threat
"Let's find a better job"

Primary appraisal moderators:

  • sense of control. If the individual feels (no need to actually be) in control = less stress. But inappropriate sense of control increases stress: individuals blame themselves for an event they actually could not influence, especially if the event is big: "it's my fault if my car's brakes broke and it caused an accident".
  • predictability. Know when stressor happens (and/or does not happen) reduces stress. Unless stressor very frequent or very rare, or horrible outcome (e.g. earthquake).
  • ambiguity. If information on the stressor is vague, stress increases.
  • centrality. If the outcome is important to the individual, stress increases.
- Optimists Pessimists
Face problems actively passively
Receive positive events wrt themselves, in general and absolute terms wrt other people, in specific and relative terms
Receive negative events wrt other people, in specific and relative terms wrt themselves, in general and absolute terms
Example: just got fired "my skills were not a good match for that company" (external) "i am a failure" (internal), "I can't do anything" (global), "I'll never get another job" (absolute)

Coping

The individual estimates how well she can cope with the stressor. If she estimates she does not have enough resources to cope with the stressor, the stress response will be bigger. Coping can happen before, during, or after a stressor, and it varies in time. When it happens before, it is called proactive coping (e.g. keep water bottle packs and a torch light at hand in case of a disaster). Even when given information, if people feel like they can not change the outcome, or if they underestimate the problem, they may not pro-actively cope.

Avoidance or minimization are effective coping strategies for short-term stressors. Vigilance and confrontation consist of gathering information or take direct action, and are more effective in the long-run, but fail if the information is of poor quality (e.g. individual googles "soar throat" symptoms and finds herself on a page about a deadly disease). Social support from others is a form of coping; the individual reduces her stress response by receiving moral support, information about the stressor, or tangible resources (money, workforce, ...) to overcome the stressor.

Coping can be problem-focused, emotion-focused, or both. Problem-focused coping is constructive (e.g. studying for an exam), and effective when the individual can have an impact on the stressor. Emotion-focused coping does not address the problem, but rather regulates the individual's emotions cognitively (how people think about the stressor, e.g. "it could be worse"), or behaviorally (doing something, e.g. jogging or eating chocolate to feel better). Emotion-focused coping is effective when the individual does not have control on the stressor.

In general, optimists deny less and cope better than pessimists. For instance, Type A individuals are competitive, easily provoked, fast-paced, and impatient. They have more risky behaviors, are less likely to receive social support, and have bigger physiological responses. Hence, they are more sensitive to stress. Moreover, according to a 2006 study (see also the pdf), Big 5's Neuroticism is related to distress and emotion-focused coping, while Conscientiousness is related to task-focused coping.

Methods for assessing stress

  • After an unpredictable/random trauma (e.g. a disaster): from groups or individuals. Problem: getting a baseline before the stressor happened. Solution: compare with similar groups or individuals who were not exposed to the trauma.
  • Life events: go through individual's recent events to assess her current stress level. Depending on the category of the individual, each event has a standard weight (e.g. for undergrad students, "death of relative" = 100 points, "got a ticket" = 20 points).
  • Daily stressors: going over recent events or maintaining daily diary (prompted by researchers every day at the same hour).
  • Lab experiments: standardized stressor, influence on appraisal (but appraisal ultimately depends on the individual), can measure physiological response, but not generalizable.

Physiologically

Cortisol is a hormone released by the adrenal gland in response to stress. Its function is to have the body generate energy by breaking body fat into glucose. In the circadian rhythm, it naturally peaks at wake up, and falls at sleep time.

Cognitive tasks such as mental arithmetic increase the concentration of cortisol in the blood. Public speaking increases it even more. The two combined generate more than the sum of each. Public speaking exposes our differences with other people, and invites criticism: it is a social evaluative threat. This threat is increased if we are captured on permanent record, in front of a critical audience, or compared to others negatively. On the other hand, emotion induction (such as watching a scary movie) or exposure to noise do not influence the cortisol level.

Uncontrollability increases the cortisol level. Hence, false feedback to a stressful task will increase the cortisol level. Changing the task difficulty on the fly, harassing the individual under stress, or adding noise and distractions increases stress. An uncontrollable social-evaluative threat generates the biggest cortisol response, and a slow stress recovery: the cortisol level remains high longer.

Novelty and diversity also seem to increase the cortisol response. Facing many stressors at a time seems to increase the cortisol level logarithmically with the number of stressors. On the other hand, facing a stressor as a group reduces the individuals' cortisol response. Similarly, in a 1991 study, women's stress response was found to be smaller if their pet rather than their friend was with them: as opposed to the friend, the pet provides support without judging.

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.