Human beings evolved with a protective mechanism called the ‘fight or flight response’.
Basically – if we are confronted with any real or perceived threat or danger our body releases certain natural chemicals (such as Adrenaline and Cortisol) which alter various nervous functions, giving our body a burst of energy and strength so that we are better able to ‘fight’ or ‘flee’.
This surge of ‘friendly’ adrenaline results in what could be described as ‘anxious feelings’ – our nerves feel ‘on edge’ and our mind is in a ‘worried state’ ready for action
It can also be called the ‘Fight, Flight or Freeze response’’ because in some dangerous situations staying perfectly still is a useful response (like if a poisonous insect was nearby)
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