IBP Stress, Health and Disease Lecture Summary

Stress, Health and Disease Notes
Lecture 1: Stress Response and Evolution
Ch 1,2,3, R 1
 Stressor every possible threat to the attainment of psychobiological goals
 Stress Response adaptive psychobiological reaction to a stressor
- Negative emotional psychobiological response
 Stress Responses:
- Psychological negative emotions, anger, anxiety, depression
- Bodily heart palpitations, sweating, muscles contract, faster breathing, dry mouth,
tremble. nausea. Stomach issues
 Stress is a worldwide epidemic, 70-80% of doctor visits caused by stress
 Acute stress response chronic stress response dysregulation tissue damage,
lowered defense organic disease
 Nearly every disease seems to have a higher chance of occurrence when organisms are
chronically stressed
 Psychobiological routes of stress:
- Health behavior route (indirect route) involves external factors e.g. stress can
cause us to smoke more or drink more
- Many different indirect routes
- Direct route from stress via its psychobiological effects to disease

Important figures through history:
 William James mind and body always linked in everything- nothing that happens in the
mind does not have an effect on the body
 Cannon (1932) fight/ flight response- fast reaction adrenaline (epinephrine) response
to psychological stress
- No place for fight or flight in human world- can lead to chronic stress
 Selye (1956) stress response to physical and psychological threat – non specific
response
- Gluco-corticosteroids (cortisol)

Main messages:
1. Brief stress is okay but prolonged and frequent stress is bad
2. Stress response is phylogenetically old ( generally the same for all animals including
humans)
- Stress response is functional reaction to any conceivable threat- from physical to
psychological- and on any conceivable level- from molecular to macro social
3. Psychological score of stressor = uncontrollability or unpredictability
4. Function of Biological stress response (fight or flight):
- Transport oxygen and fuel to muscles
- Save fuel and building material by suppressing other bodily activity
- Limiting damage and negative sensations
5. Stress in humans: preparation but without action!

,Stress response:
 Regardless how complex or culturally determined human stressors seem to be, effects
on body via old biological and basal psychological routes
 3 consequences of old phylogenetic stress response
1) function is still- remove the threat or escape,
2) effect on the body via biological routes shared with other animals,
3) effect on body also via old basal psychological factors
 Basal psychological factors that determine stress on body:
- Stressor dimensions adversity (nature of threat, uncontrollability and
unpredictability, duration
- Response patterns fight/flight and giving up/ withdraw

 Adversity:
- Physical direct threat by physical integrity eg. Cold, heat. Toxins. Infections,
bleeding, violence, hunger, thirst, exhaustion, sleep deprivation
- Psychological perceived threat of physical integrity or psychological integrity eg.
Security, safety, belongingness, intimacy, sex, autonomy, prestige, self actualization
- Threat for humans are often social
 Uncontrollability and Unpredictability:
- Experiment with rat where they can control electric shock or not
- Effects of uncontrollability in experiments stomach/intestinal ulcers, high stress
hormones, depleted storage of neurotransmitters in the brain, suppression of
immune responses- unpredictability has similar negative effects
- Uncontrollability of reward can also be stressful
- Duration of the response
 Fight or Flight action need physiological response = bodily exercise response +
perceived adversity + decreased control negative emotions
- Preparation for action
- Maintenance of action
- Meant to regain control of the situation
 During a stress response your body reacts much like the exercise response with
increased heart rate and increase blood pressure
Comparing stress with other causes of disease:
 Biological vulnerabilities heritable factors, acquired bodily conditions (pregnancy),
disease agents and other direct disease triggers (bacteria)
 Physical Vulnerabilities physical stressors such as extreme temperatures or
dangerous environments, physical violence, accidents, undernourishment
 Psychological Vulnerabilities psychological stressors (poor living conditions, life
events, illnesses, hassles, emotions, worry), health cognitions (symptom perception,
beliefs about risk), health behavior (smoking)


The Nervous System:

,  Basic Physiology of stress response:




 HPAC hypothalamus pituitary adrenal cortical system
- Hypothalamus CRH Pituitary ACTH Adrenal Cortex Cortisol organs
- Sustaining SAM effects, suppressing immune activity and other non-essential
activity, save energy, to support fight/flight action, no interference of pain experience
with action
 SAM Sympathetic Adrenal Medullary System
- Sympathetic NS Adrenal Medulla Adrenaline Organs
- Increased heart rate and blood pressure, local constriction of peripheral blood
vessels, preparation for action, more glucose, more sweating
Consequences:
 Consequences of chronic high SAM activity excessive parasympathetic inhibition and
sympathetic arousal and nor adrenaline distorts
- Blood pressure regulation hypertension
- Heart Rhythm sudden death
- More lipids/ free fatty acids in blood atherosclerosis
- Cellular immunity immunological disorders, infections and allergies
 Consequences of HPAC:
- Prolonged immunosuppression  infections, cancer
- Slower growth, faster aging, etc..