Psychological factors in health and illness Flashcards
stress definition
refers to experiencing events or situations that are perceived as endangering ones physical and or psychological wellbeing
models of stress
stress as a stimulus
stress as a response
stress as an interaction
what is the stimulus model of stress
what are the causes of stress
focus on stressors
may be acute e.g. catastrophes, life events
or chronic: occupational stress, conflict, prolonged circumstances
how may stresses be measured
scales and questionnaire
daily hassles scale
social readjustment rating scale
daily hassles scale
irritating frustrating distressing demands that characterise everyday transactions with the environment
rating 0 to 5 for how often each factor causes you stress
social readjustment rating scale
major life events
tick the events experienced in the last year
use of the social readjustment rating scale
participants scored LCUs over 1 year
positive correlation with the probability of illness in the subsequent year
scores greater than 300= subsequent ill health in 70% of the sample
limitations of the SRRS
item selection is culturally specific
individual differences in significance events
duration
confounded by illness
moderating factors such as coping
shows correlation rather than a cause
what is the response model of stress
physiological/biological models:
-fight or flight
-general adaptation syndrome aka stress response-stress reactivity
stress response and consequences of prolonged stress
components of the stress response and possible pathological consequences
mobilisation of energy -> fatigue, muscle wasting
suppression of immunity -> reduced disease resistance
analgesia -> apathy
what are the 2 pathways of physiological response
neuroendocrine immune pathway
sympathetic nervous pathway
neuroendocrine immune pathway
HPA
stressor
hypothalamus (CRH)
pituitary gland (ACTH)
adrenal glands- cortex (corticosteroids)
immune system down
sympathetic nervous system pathway
stressor
hypothalamus
ANS-SNS
adrenal glands- medulla (adrenaline and noradrenaline)
increased blood pressure
sympathetic adrenal medullary
threat trigger an instantaneous hormonal change and physiological reponsr to ready for action- cascade effect
hypothalamus activates the SNS via the ANS to the adrenal glands, produces adrenaline and noradrenaline
HPA axis activated to keep the body on high alert through cortisol release
threat passes, cortisol decreases and Pin is activated
neuroendocrine immune pathway (HPA axis)
HPA axis activated to keep the body on high alert through cortisol release
immune system decreases
associated with chronic stress
response model: measurement
endocrine system- ACTH, cortisol
cardiovascular system- cardiac output, BP
skin conductance- sweat glands controlled by SNS
immune system- leukocytes, antibodies
little correlation between the measures
what role does stress play in the immune response
appears to be a neurophysiological basis (increased stress, increased cortisol, decreased immune function)
pathways aren’t fully understood
chronic stress
stress-induced increased cortisol prolonged secretion is detrimental physically and psychologically
down-regulation or resistance of the glucocorticoid receptor that blocks cortisol binding, similar to mechanism of type 1 diabetes
normal cortisol breakdown
cortisol binds to the glucocorticoid receptor GR
acts as an anti-inflammatory
experimenting the stress and cold
increased stress exposed volunteers were more likely to develop colds than decreased stress
stress related to immune function
evidence of stress and wound healing
students received skin wounds
those who received prior to exams took longer to heal
high stress and worry impaired wound healing
evidence based between stress and immune function
link between psychological factors and susceptibility to infectious diseases and wound healing
supported by life event research e.g. autoimmune diseases, cancer, CHD
life event research
explores possible links between (potentially stressful) life events and ill health
summary of infection, inflammation and immunity
endocrine pathway through HPA axis where brain communicates with target cells through hormone production
adrenal cortex responds to stimulation of ACTH by producing glucocorticoids such as cortisol and DHEA (dehydrepiandrosterone)
effects are beneficial or detrimental
