Biopsychology - Fight-or-flight response

Question 1

What happens when a person experiences a stressful or threatening situation?

Answer 1

The heart beats faster, their breathing becomes more rapid and their muscles tense. These reactions to stressful situations are known collectively as the fight or flight response

Question 2

How is the amygdala and hypothalamus involved in fof?

Answer 2

The amygdala is mobilised when an individual faces a threat. The amygdala associates sensory signals with emotions such as fear or anger. It then sends a distress signal to the hypothalamus which communicates to the rest of the body through the sympathetic nervous system.

Question 3

Explain the process of fight or flight response

Answer 3

1. The hypothalamus recognises that there is a threat.
2. It sends a message to the adrenal gland (specifically the adrenal medulla)
3. This triggers the release of adrenaline to the endocrine system and noradrenaline in the brain
4. This prompts physical changes

Question 4

Name physical changes of fof and their effect

Answer 4

Increased heart rate - to speed up the blood flow to vital organs and improve the spread of adrenaline around the body

Faster breathing rate - to increase oxygen intake

Muscle tension - To improve reaction time and speed

Pupil dilation - To improve vision

The production of sweat - to facilitate temperature regulation

Reduced functioning of the digestive and immune systems - to save energy for prioritised functions, such as running

Question 5

What happens when the threat has passed?

Answer 5

The parasympathetic branch of the autonomic nervous system dampens down the stress response. The parasympathetic branch slows down the heartbeat again and reduces blood pressure.

Question 6

What is the HPA axis? What is its function?

Answer 6

It is a stress response system consisting of the hypothalamus, the pituitary gland and the adrenal glands.

Question 7

What is the role of the hypothalamus in fof as part of the HPA axis?

Answer 7

In response to continued threat, the hypothalamus releases a chemical messenger, CRH which is released into the bloodstream in response to the stressor

Question 8

What is the role of the pituitary gland in fof as part of the HPA axis?

Answer 8

CRH causes the pituitary to produce and release ACTH. From the pituitary, ACTH is transported in the bloodstream to its target site in the adrenal glands.

Question 9

What is the role of the adrenal glands in fof as part of the HPA axis?

Answer 9

ACTH stimulates the adrenal cortex to release various stress-related hormones , including cortisol. Cortisol is responsible for several effects in the body that are important in the fof. Some of these are positive e.g a quick burst of energy and a lower sensitivity to pain, whereas others are negative, lowered immune response.

Question 10

Limitations of fof

Answer 10

• ‘tend and befriend’ response
  Taylor et al suggests that, for females, behavioural responses to stress are more characterised by a pattern of tend and befriend than fight or flight. Women may have a different system for coping with stress because their response in the context of being the primary caregiver of their children. This finding, explained in terms of the higher levels of the hormone oxytocin in females suggests that previous research, which has mainly focused on males, has obscured patterns of stress response. Beta bias
• Fight or flight does not tell the whole story
  Gray (1988) argues that the first phase of reaction to a threat is not to fight or flee, but to avoid confrontation. Suggests that before responding with attacking or running away, most animals (including humans) typically display the ‘freeze response’. ‘stop look and listen’
• not applicable to modern day chronic stress
• deterministic , we lack free will over our response
• early research was typically conducted on males (androcentrism) and consequently, researchers assumed that the findings could be generalised to females. Beta bias