the physiology of stress Flashcards
1
Q
who created GAS?
A
Hanse Selye
2
Q
what are the 3 stages of GAS?
A
- alarm reaction
- resistance
- exhaustion
3
Q
what sort of stress was GAS useful for and why?
A
- acute stress
- believed if stress prolonged then serious damage could occur
4
Q
explain Alarm reaction?
A
- once stressor is perceived responses for fight or flight is activated
- raised heart rate
5
Q
explain resistance?
A
- body attempts to adapt by resisting stressor
- physiological activity is greater=more energy used
- seems like they’re coping but bodies resources have been consumed= harmful as stress hormones produced in large quantities
6
Q
explain exhaustion?
A
- adaption to chronic stressor now failing, now re-experiencing symptoms that appear in alarm stage
- adrenal glands may become damaged, stress related illness more likely
7
Q
evaluate a supporting claim of GAS?
A
- Selye experimented on rats, subjecting them to stressful situations e.g.. extreme cold
- found same typical collection of responses shown by rats regardless of the stressor
- rat showed resistance and exhaustion stages= body’s response is a physiological reality in rats
8
Q
what is the GAS viewed as?
A
-a way in which the body reacts to all stressors
9
Q
evaluate a negative aspect of GAS?
A
- gas believe’s body response is non specific
- a replica of procedure with monkeys measured cortisol levels in urine depending on stressor
- challenges GAS as it shows specific stressors produce different patterns of response
- eg. cortisol levels levels increased when heat decreased
10
Q
what does the physiological response believe?
A
- SAM/sympathomedullary pathway
- chronic stressor (HPA)yj
11
Q
Explain the SAM response?
A
- individual perceives a stressor as threatening, sympathetic branch of ANS is activated by HYPOTHALAMUS Which connects the brain with other organs in the body
- sympathetic arousal stimulates medulla to release adrenaline and noradrenaline in to the blood
- causes the heart to beat faster
- convertes glycogen to glucose and releases into blood to provide energy for fight/flight
- when stressor is no longer a threat parasympathetic is activated and arousal associated with f/f decreases `
12
Q
how does the body respond to chronic stress?
A
- hypothalamus is activated
- signal is send to sympathetic nervous system
- this produces hormone corticotrophin (CRF)
- detected by the anterior lobe of the pituitary gland
- causing release of (ACTH) into blood
- ACTH is detected by adrenal cortex and secretes cortisol
13
Q
what is the roll of cortisol?
A
- helps body to cope with a stressor
- it restores energy + supplies power to stress response
- but can damage the body as it surprises the immune system
14
Q
explain the negative feedback loop? (chronic stress)
A
- levels of cortisol in blood are monitored by pituitary and hypothalamus
- high levels of cortisol trigger deducted in CRF and ACTH=reduction of cortisol
15
Q
evaluate a weakness of the physiological response?
A
- bias towards male physiology
- if female responds with f/f it puts her baby in danger
- this response is then only able to be carried out by males
- women= tend and befrined
