Stress: The Physiology Of Stress

Question 1

What is stress?

Answer 1

A state of psychological strain caused by an event (stressor) that tend to disturb the functioning of the body.

Question 2

What are the main AO1 points about the physiology of stress?

Answer 2

• General Adaption Syndrome (GAS)
• The hypothalamic pituitary-adrenal system
• The sympathomedullary pathway
• Role of cortisol

Question 3

What is SAM (sympathomedullary pathway)?

Answer 3

Generally deals with the short term effects of stress.

-Fight or flight

Question 4

What is the hypothalamus-pituitary-adrenal axis (HPA)?

Answer 4

Is a complex set of direct influences and feedback interactions among 3 endocrine glands:

• Hypothalamus
• Pituitary gland
• Adrenal glands

Question 5

How does the HPA respond to a stressful situation?

Answer 5

The hypothalamus activates pituitary gland, causing ACTH to be released.
This stimulates the adrenal cortex to release cortisol for example.
These stress hormones have a number of functions: e.g. cause liver to increase the release of glucose.

Question 6

What is the role of cortisol?

Answer 6

When chronic stress is experienced cortisol remains high because threat of stressor stays.
Called ‘stress hormone’ because it helps your body respond to stress.
Increases and decreases throughout the day.
Long term release of cortisol can cause Cushing’s syndrome.

Question 7

What is Cushing’s syndrome?

Answer 7

A disorder that occurs when your body makes too much of the hormone cortisol over a long period of time.

Question 8

Describe the effects of cortisol on the body over a short period of time?

Answer 8

• Helps regulate blood glucose
• Maintains BP and cardiovascular function
• Helps reduce inflammation
• Regulates the metabolism of proteins, carbs and fats.

Question 9

What are the long term effects of cortisol?

Answer 9

• High BP
• Immunosuppression + slow wound healing
• Disrupted sleep
• Impaired cognition

Question 10

What study looks at the effects of cortisol?

Answer 10

Vgontzas (2013) - found chronic insomniacs had increased PAS system leading to high levels of ACTH and cortisol.

Question 11

Who was general adoption syndrome (GAS) research made by?

Answer 11

Hans Selye (1936)

Question 12

What is GAS?

Answer 12

A 3-stage set of physiological processes which prepare, or adapt, the body for danger so that we are ready to stand a better chance of survival if relaxed when faced with a threat.

Question 13

What was the method of Selye’s GAS study?

Answer 13

Based off work with rat, and later on patients.

-Injected the rats who became ill (e.g. developed stomach ulcers) even when given harmless injections.

Question 14

What did Selye conclude from his research?

Answer 14

That the rats became ill for the stress of the injections and that humans react the same way.
Selye termed this way of response as GAS

Question 15

What are the 3 stage in GAS?

Answer 15

1. Initial alarm reaction stage, occurs shortly after stressful event.
2. Followed by resistance stage, during which body’s ANS resists impact of stressor.
3. If stress continues, the exhaustion stage, when body fails to cope with distressing stimulus.

Question 16

Evaluation points of Selye’s GAS

Answer 16

• Research was experimental therefore objective measure is possible and supported by scientific research.
• GAS ignores individual differences that characterise humans, e.g. gender, personality - meaning it is not universal.