Fight or flight response

• Fight or flight response


  An evolutionary survival mechanism in response to a threat
• The body returns to homeostasis


  After the threat has passed
• Fight or flight response

  1. Stressor detected by Hypothalamus

  2. HPA axis in the endocrine system activated

  3. Pituitary gland releases ACTH

  4. Adrenal cortex releases cortisol

  5. Hypothalamus activates Sympathetic branch of ANS

  6. Adrenal medulla triggered via Sympathetic Adrenomedullary pathway, releasing adrenaline
• Adrenaline


  • Psychological effects: increased anxiety, attention and alertness
  • Physical effects: increased blood flow to brain and skeletal muscles, decreased blood flow to skin and digestive/immune system, dilated pupils, faster breathing rate
• The fight or flight response is not designed for the modern world, it is 'maladaptive' in most situations
• The fight or flight response is frequently triggered by stimuli that can't be run away from or fought (e.g. exams)
• In the short term, the fight or flight response


  Results in acute stress, a response to immediate pressures, exciting in small amounts and giving you focus and energy
• Long-term frequent triggering of the fight or flight response


  Results in chronic stress, which can result in stress-related illness affecting the immune and circulatory systems