A2 Mock - Biological Explanations 2 (Chronic Stress)

Question 1

Explain Cortisol

Answer 1

If the stressor is chronic (lasts a long time) then the body uses a physiological response called the the hypothalamic-pituitary-axis or HPA. The hypothalamus controls this response and initiates a change in stress hormones from adrenaline to cortisol.

Question 2

Explain the HPA pathway

Answer 2

The part of the hypothalamus that acts as an endocrine gland releases corticotrophin-releasing hormone (CRF). This targets the pituitary gland which, in response, releases adrenocorticotropic hormone ACTH). This, in turn, causes the release of the hormone cortisol from the adrenal cortex. Cortisol releases energy stores in the liver and from fats so we can cope with the longer term
stress situation.

Question 3

What is Immunosuppression?

Answer 3

While cortisol is useful in helping us deal with stress in the long term it can reduce the effectiveness of the immune system. For example Keicolt-Glaser et al found that the natural killer cell activity (an immune system cell) was lower in medical students during the exam period than a month before. If the immune system is low, we will be more open to diseases and illness

Question 4

What is decreased memory?

Answer 4

Cortisol may also affect our memory. For example kuhlmann (2005) found that women who were given cortisol and given a list of words to recall showed significantly decreased recall than a control group. Therefore stress may affect our ability to recall in, for example, exam situations!