Adrenaline and the fight or flight response

Question 1

What is meant by appraisal of stressor?

Answer 1

1. Body appraises situation using sensory systems and stored memories
2. Hippocampus and amygdala try recognise emotional reactions to stimuli and access stored memories for potential danger
3. If situation is appraised as stressful, the hypothalamus is alerted
4. Hypothalamus controls systems that have central roles in stress response= HPA axis and SAM pathway

Question 2

What does the SAM pathway do?

Answer 2

1. Situation is perceived as stressful due to memories, emotions, instincts, etc..
2. Hypothalamus (CNS) is alerted which recognises the stress as acute
3. SAM pathway is activated
4. This stimulates the adrenal gland (specifically the adrenal medulla)
5. The adrenal medulla secretes the hormones adrenaline and noradrenaline
6. These hormones prepare the body for fight or flight and causes bodily effects like an increased heart rate

Question 3

What are some effects of the fight or flight response?

Answer 3

1. Increase in perspiration to cool down body
2. Pupils dilate to improve vision
3. Increase in respiration to increase oxygen in blood
4. Increase in heart rate and raised blood pressure to increase blood flow to organs and spread adrenaline around the body
5. Increase in blood flow to muscles for muscular tension to increase reaction time
6. Reduced activity in digestive system to save energy

Question 4

How does adrenaline cause faster respiration?

Answer 4

By increasing the amount of available glucose to intercostal muscle cells to enable the lungs to work faster and increase oxygen intake