Fight or flight response

• If a situation is seen as stressful/ dangerous, the amygdala sends a distress signal to the hypothalamus, which communicates with the body through the SNS.
• If a stressful or dangerous situation requires a short-term response the sympathomedullary pathway (SAM pathway) is activated, triggering the fight or flight response.
• The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS) are activated during the fight or flight response.
• The parasympathetic nervous system slows down our heart rate and breathing rate and reduces our blood pressure.
• The main hormone involved in the fight or flight process is adrenaline which is released from the adrenal gland.
• Adrenaline triggers physiological changes in the body like increased heart rate, pupil dilation and increased blood flow. which creates a state of arousal necessary for the fight or flight.
• When someone enters a potentially stressful or dangerous situation, the amygdala, which is part of the limbic system is activated.
• The amygdala responds to sensory input (what we see, hear, smell, etc.) and connects this with emotions associated with the fight or flight response (e.g. fear and anger).
• Fight or flight response.

  A) amygdala

  B) hypothalamus

  C) SAM

  D) adrenal medulla

  E) medulla

  F) adrenaline

  G) noadrenaline

  H) physiological

  
• The parasympathetic nervous system acts like a brake and reduces physiological arousal brought on by the sympathetic nervous system.
• The Pituitary Adrenal System is a system in the body which facilitates the release of energy in a stressful situation, particularly a chronically stressful situation.
• Effects of adrenaline

  • Increased heart rate and blood pressure
  • Pupil dilation
  • Reduced activity in the digestive system
• ACTH stimulates the adrenal cortex into releasing hormones such as cortisol.
• Cortisol is important for the fight or flight response and provides quick bursts of energy and lower sensitivity to pain
• Cortisol also causes impaired cognitive functioning and suppresses the immune system.