Lecture 5 Flashcards
which organs only under SNS control?
SNS control
> sweat glands (SCL)
> heart muscle (left ventricle)
> adrenal medulla
> blood vessels
what are the main differences between arteries and veins with regard to blood pressure?
arteries: thick walls, muscle walls
> have to deal with blood pressure
veins: valve, low blood pressure
> valves used to prevent blood from going in the wrong direction
where is blood pressure measured?
in the main arteries
what are 2 mechanisms that increase/control blood pressure?
- vasoconstriction
> under SNS control
- increase cardiac output
> under SNS control (contractility)
> under PNS control (vagal nerve)
what heart state reflects systolic/diastolic blood pressure?
systolic: moment of highest contraction of left ventricle
diastolic: last moment of relaxation of left ventricle, before start contraction
why does blood in the arteries pulsate?
the aorta is elastic and stores the pressure
> then releases
what does a higher RSA reflect?
higher respiratory sinus arrhytmia
> higher heart period variability
> higher activity of vagal brake
> higher PNS activity
what are the psychological advantages/disadvantages of laboratory stress management?
advantages:
> type, duration and intensity stressor can be standardized
disadvantage:
> stressors are not for real
> stressors are not complex enough
what are the physiological advantages/disadvantages of laboratory stress measurement?
advantages:
> standardisation of factors with physiological confounding effects (e.g. posture, physical activity, environment etc)
disadvantages:
> stressors are of low intensity
> stressors are of short duration, only measurement of fast heterostatic responses, no measurement of slow allostatic counterregulatory responses
what are the psychological advantages/disadvantages of ambulatory stress measurement?
psychological
advantages:
> incremental validity
> higher ecological validity
disadvantages:
> no control over stress exposures
what are the physiological advantages/disadvantages of ambulatory stress measurements?
physiological
advantages:
> physiological responses to prolonged stress exposures can be measured
> sleep can be measured
> higher predictive validity
disadvantages:
> higher risk of signal loss
> no control over confounders (but they can be assessed)
ambulatory recordings: what accounts for most changes in heart rate?
most changes in heart rate can be accounted for by changes in physical activity
what are 2 strategies to deal with posture/activity effects in ambulatory measurement?
- standardize - only compare similar states of physical activity
> e.g. sitting only, standing only, walking only etc
> but you will loose data
- mathematical correction for physical activity
> robust
what is EMA?
EMA: ecological momentary assessment
> record physical activity via self evaluation
> via smartphone/ipod etc
