Stress & Health

1. Stress & Health November 25th : Lecture 22

2. Lecture Overview • Stress • Effects of Stress • Perceived Control • Physiological Thriving • Reducing Stress

3. Stress • Stress is operationalised in two ways: • Psychological events causing stress • Physiological responses to stress

4. Psychological Stress • Degree to which people have to change and readjust their lives in response to an external event

5. Psychologically Stressful Events • Both “good” and “bad” things can cause significant stress

6. Physiological Stress • Stress on the body caused by physical or psychological stressors

7. Allostasis • Body’s ability to adapt to constantly changing environments to maintain homeostasis • Tight Allostatic System • One that moves from high to low levels of arousal flexibly and fluidly depending on demands

8. Allostatic Load • A chronically elevated state of arousal which damages the body and makes it less able to flexibly adapt to the environment • Result of chronic stressors • Associated with heart disease, diabetes, suppressed immunity, hypertension

9. Effects of Stress • Stress & Performance • Stress & Health

10. Stress & performance • When motivated to perform well, the way your body responds to the stressor can either IMPROVE or INHIBIT your performance • Improving Performance: Challenge • Inhibiting Performance: Threat

11. Challenge & Threat

12. Why Respond with Challenge or Threat? • What you expect is what you get … • … it all comes down to how you appraise the situation: Personal Resources Situational Demands Personal Resources Situational Demands > <

13. Cognitive Appraisals & Cardiovascular Responses • Tomaka, Blascovich, Kibler, & Ernst (1997) • Method: • Have participants complete verbal math task • Before task, asked participants: • Q1. How well can you can cope with the upcoming task? • Q2. How threatening is the upcoming task? • Divide participants into 2 groups: • Challenge Appraisals: Q1 > Q2 • Threat Appraisals: Q1 < Q2

14. Cognitive Appraisals & Cardiovascular Responses • Tomaka, Blascovich, Kibler, & Ernst (1997) • Results: Cardiac Output by Cognitive Appraisals

15. Cognitive Appraisals & Cardiovascular Responses • Tomaka, Blascovich, Kibler, & Ernst (1997) • Results: Performance by Cognitive Appraisals

16. Extreme Stress & Memory • In response to extreme stressors, body releases catabolic hormone cortisol • Cortisol reduces memory and linguistic functioning

17. Cortisol & Cognitive Performance • Cortisol: • Decreases hippocampal mass in rats • Restricts blood flow in the hippocampus • Reduced linguistic complexity among humans giving speeches

18. Stress & Health • Stress & Immunity • Stress & Long-Term Health

19. Stress & Immunity • Psychological stress decreases immune functioning, making you more susceptible to disease

20. Cohen’s Hotel Study • Cohen, Tyrrell, & Smith (1991) • Method: • 420 healthy adults invited to stay a week in a hotel • Completed measures of life stress • Were exposed to common cold viruses through nasal spray • Monitored for 7 days post-exposure

21. Cohen’s Hotel Study • Cohen, Tyrrell, & Smith (1991) • Results:

22. Stress & Long-Term Health • Revisiting Allostatic Load … • Chronic stress predicts: • Hypertension • Type II Diabetes • Weakened immune system

23. Perceived Control • The belief that we can influence our environment in ways that determine whether we experience positive or negative outcomes

24. Self-Efficacy • The belief that you can competently complete the actions necessary to deal with a demanding situation

25. Learned Helplessness • The acquired sense that one can no longer control the environment, with the result that one gives up trying • Perceive negative events as: • Stable: Caused by factors that don’t change with time • Internal: Caused by you • Global: Causes of one negative event apply to other events

26. Learned Helplessness • Seligman & Maier (1967) • Method: • Phase 1: Two groups of dogs receive shocks while strapped in hammocks • Group A had control: Lever next to nose turned off shocks • Group B had no control: No lever to affect shocks, but same duration of shocks as Group A • Phase 2: Brought into divided pen (2 compartments, separated by short barrier) • Electrified floor of one compartment 10 seconds after a buzzer rings • If dog leaps to other compartment in less than 10 seconds, they won’t get shocked

27. Learned Helplessness • Seligman & Maier (1967) • Results: Time spent in first compartment after buzzer rang

28. Physiological Thriving • But sometimes … • Stress = Thriving • 2 Aspects of “Positive” Stress: • Acute stressors (instead of chronic) • Complete relaxation in between stressors

29. Physiological Toughening • Fast and strong mobilization of bodily stress responses during a stressor coupled with rapid recovery after the stressor is the healthiest response

30. Physiological Toughening in Animals • Animals exposed to chronic stressors showed allostatic load • Animals exposed to intermittent stressors showed toughening • Increased immune response and suppression of cortisol

31. Physiological Toughening in Humans • Performance of Swedish students directly predicted by: • Strong hormonal response to an exam • Rapid return to baseline post-exam

32. Physiological Thriving • Epel, McEwen, & Ickovics (1998) • Compared to no stress or chronic stress, intermittent stressors lead to: • More effective coping with subsequent stressors • Healthier immune system • Longer cell life

33. Psychological Thriving • Epel, McEwen, & Ickovics (1998) • Compared to no stress or chronic stress, intermittent stressors lead to: • Responding positively to past stressors leads to perception of benefiting from stressors • Viewing stressors as a challenge improves responses to subsequent stressors

34. Taking Stock • The ability to recover from stressors can turn potentially damaging events into empowering ones • Appraisals of resources vs. demands affect your physiological ability to perform • If you feel threatened … • Boost your resources: Practice makes perfect! • Re-appraise the situational demands • Know that if you can go in with confidence, your body will back you up! • Challenge responses are positive responses to stressors => Physical Thriving & Resilience to Future Stressors

35. Reducing Stress • Exercise • Meditation

36. Exercise & Stress Reduction • Berger & Motl (2000) reviewed > 80 studies • Exercise reliably improves mood and reduces stress • Caveats: • Regularity: ≥ 3 x per week • Duration: ≥ 20 minutes per session • Intensity: ≥ moderate intensity (break a sweat)

37. Meditation • A class of techniques designed to influence an individual’s perception of consciousness through the regulation of attention

38. Benefits of Meditation • Benefits of meditative practice: • Improved immune functioning • Decreased stress, improved well-being • Decreased relapse of chronic depression • Faster recovery from disease • Increased left pre-frontal asymmetry

39. Left Pre-Frontal Cortex Asymmetry • Asymmetry in activity levels of left and right prefrontal cortex • The “Monk Experiments” • Left activity > 7 x right activity • More Generalizeable Populations: US Employees

40. Relaxation & Meditation • When to meditate? • Whenever you think of it! • Try meditating for 5 min./day for overall improvement • Relaxation techniques to deal with immediate stressors: • http://www.utsc.utoronto.ca/psyb10/documents/relaxation.pdf • Focusing on Breath • Given that: • Inhaling increases your heart rate, and • Exhaling decreases your heart rate • Exhale longer than you inhale to slow heart rate

41. What Doesn’t Kill You Makes you Stronger • Next time (Wednesday, 12/2): • Last Lecture! • Relevant Websites: • Toronto Meditation Guide: • http://torontomeditationguide.org/ • CMHA Coping With Stress Info & Resources: • http://www.cmha.ca/english/coping_with_stress/