Psychoneuroimmunology Flashcards
What is PNI?
Links between emotions and health were part of pre-modern thought e.g. humoural medicine
Classic early study found decreased phagocyte activity in response to stress
Substantial empirical evidence to demonstrate and explain links between psychological states and immune function
Links between immunity and endocrinology
Increasing evidence of pathogenic involvement in disease not previously thought to involve infection and inflammatory processes
3 phases of general adaptation syndrome
Alarm
Resistance
Exhaustion
Alarm
Body is mobilised against the stressor
Resistance
Arousal stays high as body defends/ adapts
Exhaustion
Resources are depleted, resistance may collapse
Why is prolonged stress harmful?
Allostatic load
If stress is prolonged, allostatic load accumulates
- decreased cell mediated immunity
- inability to shut off cortisol in response to stress
Protects in the short term , can harm in the long term
Allostasis
Body actively copes with stress by trying to find a new balance
Stress
Negative experience accompanied by predictable changes and aimed at altering the stressful event and/ or accommodating its effects
- biochemical
- physiological
- cognitive
- behavioural
Transactional model
Stressor ->
Primary appraisal ->
Secondary appraisal ->
Stress
Primary appraisal
Positive/ negative/ neutral
Harmful/ threatening/ challenging
Secondary appraisal
Can coping abilities/ resources meet the harm, threat or challenge?
Perception/ expectation and experience
High amounts of stress and the perception that stress harms health are both associated with poor health and mental health
Individuals who perceived that stress affects their health and reported a large amount of stress had significantly increased risk of premature death
Reactivity to stress
People vary in their reactivity to stress
Refers to the magnitude of autonomic, neuroendocrine and immune responses to stress
Higher physiological reactivity is related to worse health outcomes in response to prolonged stress
Reactivity may vary depending on the nature of the stressor/ stress
Coping
Actions people take to reduce stress
Processes used to manage perceived discrepancies between the demands of a situation and their perceived resources
Not all coping responses are directed toward solving a problem
2 major modes of coping
Emotion focused
- behavioural
- cognitive
Problem focused: aimed at
- reducing demands of a situation and/ or
- increasing resources to deal with stressful situation
Different strategies are better suited to different stressors
Direct effects of social support
Via psychosocial influences on endocrine and immune function
e.g. people feel less stressed
Indirect effects of social support
People with better social support are more likely to adhere to medication and more likely to use health services
Depression and immunity
Negative emotions- loneliness, pessimism, depression- impair immune function
Greater susceptibility to infections
Slower wound healing
Altered immune function
- reduced number and function of lymphocytes
- reduced number and function of NK cells
- changes in pro-inflammatory cytokines
- increases in interleukin 6
More severe depression related to greater immune effects
Effects of depression may be
Direct: effect on immune function
Indirect: unhealthy behaviour/ lower adherence
Positive mood and immunity
Positive mood and personalities related to enhanced immune function
Personality
Optimism, emotional expressiveness, extraversion associated with: NK cell cytotoxicity, proliferation of helper T lymphocytes
Mood
Positive events and moods may have longer lasting effects on immune function than negative events
