Fight/Flight

• Fight-or-flight response


  • an innate, unconscious bodily response, characterised by increased physiological reaction of the sympathetic branch of the autonomic nervous system.
  • An evolutionary mechanism that increases survival chances in response to perceived threat.
• Process of fight-or-flight response once Amygdyla detects threat

  1. Hypothalamus activates sympathetic branch + Pituitary Gland

  2. Pituitary Gland stimulates adrenal cortex to secrete glucocorticoids (increase awareness of surroundings).

  3. Adrenal medulla releases adrenaline + noradrenaline

  4. Resulting in physical changes: increased hr and breathing rate (more oxygen+glucose), pupil dilates (improve vision), muscles tense (prepare for action, e.g. run away)

  5. Return to normal: Once threat is gone, parasympathetic nerve calms the body down + homeostasis is restored.
• SAM Axis


  Immediate response to stress
• Chronic Stress


  Long-term form of stress in response to prolonged emotional pressure
• HPA Axis


  Negative feedback loop that helps the body respond to stress by releasing cortisol. In chronic stress, this system becomes overactive, leading to negative health effects (e.g. immunosupression, insulin resistance, memory + mood problems)