Stress

Question 1

What is the G.A.S ?

Answer 1

General adaptation syndrome:
-3 stages which explain how the body reacts to stress.

Question 2

What is the alarm reaction?

Answer 2

the psychological response activated once a stressor is perceived in preparation for fight or flight.

Question 3

What is resistance?

Answer 3

when the body attempts to react to the stressor.
-physiological activity is higher than normal, so it uses lots of energy.
-the body’s resources are consumed at a potentially harmful rate.
-the parasympathetic nervous system is activated to conserve energy for the developing chronic stress.

Question 4

What is exhaustion?

Answer 4

when resources are drained as adaptations fail.
-symptoms of sympathetic arousal (like in alarm stage) appear.
-adrenal glands can become damaged and stress related illness is likely.

Question 5

Describe the sympathomedullary pathway for acute stress.

Answer 5

• the sympathetic branch of the ANS is activated by the hypothalamus when an individual perceives a stressor as threatening.
• sympathetic arousal stimulates the adrenal medulla to release adrenaline and noradrenaline.

Question 6

What does adrenaline and noradrenaline do the the body?

Answer 6

causes:
- increased heart rate
- tense muscles
- liver convert stored glycogen into glucose (provides fuel for fight or flight response)

Question 7

When does the sympathomedullary pathway stop?

Answer 7

ends when stress becomes chronic or when the parasympathetic nerve takes over.

Question 8

Describe the hypothalamic-pituitary-adrenal system for chronic stress?

Answer 8

• HPA takes longer than SAM to activate, but lasts for longer.
• the hypothalamus is activated when the stressor sends a signal to activate the sympathetic nervous system, but also produces corticotropin releasing factor (CRF).
• CRF is detected by the anterior lobe of the pituitary gland, causing the release of adrenocorticotropic hormone (ACTH).
• ACTH levels are detected by the adrenal cortex, which secretes cortisol in response.

Question 9

What is the role of cortisol?

Answer 9

• affects glucose metabolism by restoring and mobilising energy supplies to power the stress response.
• but, does have damaging effects (e.g: suppress the immune system).

Question 10

What is the negative feedback loop?

Answer 10

• the HPA is self-regulating via a negative feedback loop.
• levels of cortisol are monitored as the pituitary gland and hypothalamus.
• high levels of cortisol trigger a reduction in CRF and ACTH, resulting in a corresponding reduction in cortisol.

Question 11

What is the support for G.A.S ?

Answer 11

Selye (1936):
- research support on rats, subjecting them to physical stressors (i.e: extreme cold, surgical injury, etc.).
- same collection of responses (after 6-48hrs) regardless of the stressor.
- tracked rats continuing responses through resistance and exhaustion stages.

Question 12

What is the challenge for G.A.S ?

Answer 12

Mason (1971):
- replicated Selye’s procedure on monkeys, measuring response to stressors by measuring urinary cortisol (produced by HPA).
- outcomes depended on the stressor, which reduces validity of GAS by showing specific stressors produce specific responses.

Question 13

What is the strength for the physiological stress response?

Answer 13

Knowledge has practical value:
- Addison’s disease is a rare disorder of the adrenal glands where they can’t produce cortisol, so the body can’t mobilise energy to deal with a stressor.
- lack of cortisol can trigger a life-threatening Addisonian crisis (mental confusion, abnormal heart rhythm, drop in blood pressure) when a stressor occurs.
- knowledge has revolutionised treatment, where individuals self-administer daily cortisol replacement therapy.
- they should be aware of stressful situations when they might need an ‘extra’ injection.

Question 14

What is a weakness for the physiological stress response?

Answer 14

Ignores psychological factors in stress like cognitive appraisals:
Speisman et al. (1964)
- asked students to watch a gruesome medical procedure on film, while heart rates were measured.
- changes to heart rate depended on how the students interpreted what was happening.
- but if told the procedure was part of a voluntary and joyful rite of passage, heart rate decreased, which can’t be explained by physiological theory.

Question 15

How does immunosuppression happen?

Answer 15

• chronic stress produces cortisol continuously (during activation of the HPA), which interferes with the production of antibodies and so, reduces the immune system’s ability to fight off antigens

Question 16

How does stress cause cardiovascular disorders?

Answer 16

• the fight or flight response causes an increased heart rate, which causes faster blood flow through arteries, damaging the vessels, impairing heart function (leading to heart attack, stroke).
• can be indirectly from stress, through their coping mechanisms, (e.g: smoking or drinking alcohol).

Question 17

What is the main (2) pieces of research supporting the idea of immunosuppression as a result of stress?

Answer 17

Kiecolt-Glaser et al. (1984):
- investigate the effect of exams on 75 medical student.
- took blood samples (1month before exam period, and on first day of exam period).
- questionnaire measuring sources of stress and self-reported psychological symptoms.
- found decreased white blood cell activity between the 2 blood samples.
- the decrease was most apparent in students who reported feeling most lonely, or experiencing other sources of stress).

Kiecolt-Glaser et al. (1991):
- longitudinal study where the health of family caregivers of a relative with Alzheimers, and a matched group of non-carers.
- over 13 months, caregivers showed weaker cell-based immune response, but no increase in controls.
-significantly higher depression (32% of caregivers met the criteria for clinical depression, only 6% in control).
- had infectious illnesses on significantly more days than control.

Question 18

What is the main acute stress research for cardiovascular disorders?

Answer 18

• incidences of heart attacks in German football supporters during matches played during the 1996 World Cup.
• when Germany played, cardiac emergencies increased by 2.66 times compared to a control period.

Question 19

What is the main chronic stress research for cardiovascular disease?

Answer 19

• 52 countries identify major risk factors for CVDs across different cultures by comparing 15,000 people who has a heart attack with a similar number of people who hadn’t.
• workplace stress and life events were factors highly linked.
• stress was more influential than obesity, and 1/3 only to smoking and cholesterol levels.
• stress only contributes to the development of CVDs and also worsen a condition.

Question 20

What is a strength for immunosuppression linked to stress?

Answer 20

+real-world application:
- study found giving a small dose of adrenaline before surgery would stimulate the patient’s immune system and improve their chance of making a full and fast recovery.
- studies show students who took a relaxation training programme seriously had better immune function during the exam period than those who didn’t bother.