Fight or flight response

• what two areas of the brain co-ordinate flight/fight responses?

  • amygdala
  • hypothalamus
• what is the role of the amygdala in fight/flight?

  • associates sensory signals with fight or flight
  • sends distress signals to the hypothalamus
• what is the role of the hypothalamus in fight/flight?

  • acts as a command centre in the brain
  • communicates with the rest of the body through the sympathetic nervous system when it receives distress signals from the amygdala
• what are the two types of stressors

  • acute stressors
  • chronic stressors
• how does the body respond to acute (sudden) stressors?

  • sympathetic nervous system is triggered
  • sends signal to adrenal medulla, releases adrenaline into the bloodstream
  • adrenaline- causes heart to beat faster, blood pressure increases, breathing becomes more rapid, blood sugar is released
  • PNS- when the threat has passed, PNS dampens down the stress response. Slows down heart rate, reduces blood pressure, begins digestion again
• what is the body's response to ongoing stressors?

  • hypothalamus activates a stress response system called the HPA axis. Consists of the hypothalamus, pituitary and adrenal gland.
  • H- hypothalamus- releases CRH, released in the bloodstream in response to the stressor
  • P- pituitary gland- CRH causes the pituitary gland to release ACTH, which is transported to the adrenal glands
  • A- adrenal glands- ACTH stimulates the adrenal cortex to produce cortisol and other stress-related hormones
• how do the pituitary gland and the hypothalamus regulate cortisol levels?

  Negative feedback- using special receptors monitoring cortisol levels
• evaluation for fight or flight?

  • ☹️ negative consequences of chronic stressors- increased blood pressure all the time can lead to damage of blood vessels, and eventually heart disease. Cortisol can also supress an immune response
  • 😊 tend and befriend rather than fight or flight- females protecting themselves and their young through nurturing behaviours and forming protective alliances. This is a different system for coping with stress
  • ☹️ doesn't tell the whole story- also the freeze response- animal is hypervigilant and alert to danger
  • ☹️ positive rather than fight or flight behaviours- acute stress can lead to more co-operative and friendly behaviours in men and women eg- coming together during 9/11