Lecture 1 Introduction to stress & Health
Evidence level
1. Systematic review of RCT’s – most reliable findings, higher support multiple RCT’s
treatment compared in different groups
2. RCT (randomized controlled trial) – group with treatment vs. group without treatment
3. Systematic review of observational studies – different groups of people, one type of
treatment
4. Observational studies - large group, one type of treatment more reliable
5. Clinical observation – one person, one type of treatment not generalizable
Definition of stress
o Everyone can recognize stress, but harder to describe it
Shift in research of stress
o Ancient history – acute physical crisis (attack, immediate danger for body); chronic
physical crisis (malnutrition)
o New – psychological crisis, social crisis, prolonged psychological stress
Stress and Health
o Stress health (acute)
o Stress Psychological problems health
o Stress (job loss) psychological problems behavioral components (alcoholism)
health (liver)
Stress in clinical practice
o Makes people “sick” without having disease (unnecessary use of healthcare)
o Increases the odds for development of mental and physical health problems
o Negatively affects
recovery after disease or injury
effects of medical interventions
patient-physician communication (tend to forget more information when
stressed)
People don’t want to hear that mental problems are the cause of their diagnosis
(depression…)
Definition of stress
o A condition or feeling experienced when a person perceives that demands exceed
the personal and social resources the individual is able to mobilize
Homeostasis
o Bodys ideal level of oxygen, temperature… brain seeks this base level
o Stressor is anything that disrupts homeostasis – stress response is bodys action to
reestablish homeostasis
Is stress always a bad thing?
o Adaptive
Acute
Short duration
Fast recovery after stressor passed
Preparing body for danger
Signaling danger
o Disruptive
Chronic
Long duration
, Slow recovery
Early onset
Preparing the body for??
Signaling what??
o Positive consequences of exposure to stress
Short term stress (minutes to hours)
1. Increase in immunoprotection
2. Enhance mental and physical performance
Chronic stress (prolonged)
1. Suppress auto-immune disease symptoms (not experiencing the
symptoms, but still negative)
o Negative consequences of exposure to stress
Short term
- Emotional level – negative mood
- Cognitive level – concentration, memory
- Behavioral level – smoking, alcohol
- Biological level – immune, endocrine
Long term (more indirect) – chronic conditions
- Health/disease – auto-immune disease, cardiovascular disease,
cancer
What happens in our body when we experience stress?
o History of stress
Darwin – organisms capable of adapting to changing environment will
survive (cope with stressful changes)
Bernard – Milieu interieur (inner environment should be stable to cope
better)
Cannon – Fight or flight response (in danger body prepares to fight or flight
due to NTs norepinephrine and epinephrine)
o The ANS (parasympathetic and sympathetic) – works on its own, not controllable by
us (autonomous)
o CNS and Endocrine system (communication within NS through hormones and NTs)
o Signaling
CNS sympathetic adrenomedullary system – hormones (SAM) – first thing
happens when stress
Hypothalamus pituitary adrenal gland hormones (HPA-axis
produces cortisol)
Sam HPA-axis – produce stress response together
o Stress response hormones
SAM Epinephrine and Norepinephrine
HPA-axis Glucocorticoids (Cortisol, steroids, estrogens, progestins…)
o Additional stress hormone activation
Pancreas – Glucagon
Pituitary – Prolactin and Vasopressin
Pituitary + brain – Endorphins, Enkephalins
o Inhibition of hormonal systems during stress
Reproductive hormones (estrogen, testosterone…) – not adaptive to
reproduce under stress
, Growth hormones (insulin) – because energy is needed and should not be
stored
Hans Selye – pioneer of stress research
o Glucocorticoids
o Every stress leaves an indelible scar and the organism pays for its survival after
stressful situation by becoming a little older
o GAS – general adaptation syndrome alarm
Alarm stage – first encounter with stressor (high adrenaline, activated –
fight/flight response)
Resistance stage – trying to survive, higher cortisol
- Repair (want to restore energy that was needed in alarm stage)
- Dealing with stress if not possible to repair
- Looks like coping with stress
Exhaustion stage – developing health problems because body cannot win
giving up on fighting stress
- Damage to body (e.g. immune, kidney, etc…)
o Symptoms associated with GAS stage
Action stage – energy – can be also negative
Resistance stage – irritability, frustration, poor concentration (close to burn-
out)
Exhaustion stage – Fatigue, burnout, anxiety/depression, + physical
problems (damage to cardiovascular system)
o Stress is physiological response
o Non-specific response of body to any need/threat
o The reactivity hypothesis (vs. psychologists view)
Stressors accompanied by physiological response – activated closely before
the stressors, then goes up and declines again when stressor is gone
(recovers to baseline like before)
Psychologists perspective on stress
o J.W. Mason – reaction to stress varies between individuals and within individuals
(depending on time/situation)
o Susan R. Buchfield – Failure to adapt to chronic stress suggests psychological not
physiological exhaustion
o Prolonged activation model
A stressor will only affect our health when physiological effect is prolonged
(e.g. occurring long before stressor or slow recovery)
, o Michigan stress model (Kahn et al., 1964)
o What psychologists conclude
Stress response is NOT purely physiological
Not everybody has same stress response
Stress response and its duration is different between and within persons
o The cycle of stress (Reznick) – Psycho-biological response to stress
Measuring both psychological and physiological components in 4 phases
- Resting ground phase
- Tension phase
- Response phase
- Relief phase
Measuring frequency, duration and intensity
o Stress response activation due to anything that disrupts homeostasis
Adaptive
Anticipated
- Necessary prepares you to combat
- Unnecessary prepares you for nothing.. anxiety, neurosis
Acute (short term) – can have negative and positive effects on health
Chronic (long term) – can have negative effects on health
o Differences in stress response
Individual differences in stress response (response stereotype):
- Stress perception (for someone stressor stressful for others not)
- Processing
- Appraisal
- Coping – how to deal with it is different
- Genetic make up – hormones, sensitivity different
Situational differences (situational stereotype)
- Every Situation elicit different biological response different stress
response physiologically
o Stressors and stress response
Not all stressors produce same stress response
Hormonal signature for particular stressor
Body sensitivity to stress hormones
