T1 L19 Psychoneuroimmunology Flashcards
What is psychoneuroimmunology?
Link between psychological states and immune function
What does stress activate?
The sympathetic nervous system and the HPA
What does activation of the sympathetic nervous system by stress lead to?
Production of catecholamines by adrenal medulla Increase breathing rate Increase BP via vasoconstriction Increase HR Blood diverted to muscles Digestion slows
What does activation of the HPA by stress lead to?
Production of corticosteroids by adrenal cortex Increase protein and fat metabolism Increase access to bodily energy stores Inhibition of inflammation Inhibition of antibody formation
What is general adaption syndrome?
3 phases
Alarm
Resistance
Exhaustion
Describe the alarm phase of the general adaption syndrome
Body is mobilised against the stressor
Describe the resistance phase of the general adaption syndrome
Arousal stays high as body defends / adapts
Describe the exhaustion phase of the general adaption syndrome
Resources are depleted, resistance may collapse
Why is short term stress good?
It improves the immune system
What is the allostatic load?
Physiological costs of prolonged exposure to fluctuating or elevated neural or endocrine responses
Prolonged stress causes allostatic load to accumulate.
What are the measures of allostatic load?
Decreased cell-mediated immunity
Inability to shut off cortisol in response to stress
Elevated epinephrine levels
Reduces hippocampus levels
What is stress
Negative experience accompanied by predictable changes aimed at altering the stressful event and/or accommodating its effects
What is the transactional model?
There is not a simple link between the stressor and stress response
1) Stressor
2) Primary appraisal
3) Secondary appraisal
4) Stress
What is the primary appraisal?
Is it a positive, negative or neutral event?
Is it harmful, threatening or challenging?
What is secondary appraisal?
Can coping abilities / resources meet the harm, threat or challenge?
What is the link between perception / expectation and experience of stress?
High amounts of stress and 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
What is the reactivity to stress?
Magnitude of autonomic, neuroendocrine and immunological response to stress
Describe the sex differences in reactivity to stress
Men have higher levels of reactivity response when their physical competence is challenged
Women had higher levels of reactivity response when their emotional aspects are challenged
What is coping?
Actions people take to reduce stress
Process sued to manage perceived discrepancies between demands of a situation and their perceived resources
What are the 2 major models of coping?
Emotion - focused
Problem - focused
What is emotion-focused coping?
Engaging in activities that distract attention from the stressful situation such as comfort eating, alcohol, drugs, emotional support from friends
What is problem-focused coping?
Aimed at reducing demands of the situation and/or increasing resources to deal with the stressful situation
Describe how the different responses to stress can moderate the effects on immune function
Expressive writing enhances mood, immune function and health
Relaxation / self hypnosis / guided imagery may mute effects of stress on the immune system
Problem solving and stress management can reduce effects of stress on immune function
Physical activity can reduce effects of stress on cortisol
What are the direct effects of social support?
Via psychosocial influences on endocrine and immune function
What are the indirect effects of social support?
people with better social support are more likely to adhere to medication and more likely to use health services
Describe the link between depression and immunity
Negative emotions impair immune function
Greater susceptibility to infections
Slower wound healing
Altered immune function
Describe how the immune function is altered in depression
Reduced number and function of lymphocytes
Reduced number and function of NK cells
Changes in pro-inflammatory cytokines
Increases in IL-6 (mediator of fever and inflammation)
Depression is linked to a more rapid progression of what diseases?
HIV / AIDs
Cancer
Describe the link between positive mood and immunity
Positive moods and personalities are related to enhanced immune function
Positive events and moods may have longer-lasting effects on immune function than negative events.
