The Fight or Flight response was described Walter Cannon in 1927.

It describes a bodily reaction that happens in most animals including Human Beings that is a result of a stimulus absorbed by the brain through any of the senses, seen as a threat to the organism.

The body reacts with physical arousal of the sympathetic nervous system, getting the body ready for either Fighting or Flighting (running away).

The example most commonly used today is where one of our ancestors would see a sabre toothed tiger on the horizon, this instinctual response would prepare his body to fight or run away.

Although in present times there is little need for this reaction as we do not often come across a predator that fancies us for lunch, the response is still in built in us, and reacts to the stressors of modern day life.

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Some of the physical responses of the Fight or Flight reaction include:

The eyes dilate

The heartbeat and blood pressure increases,

The breathing rate increases

Muscle tone increases and levels or Adrenaline, Noradrenalin and Cortisol increase

All of these being the responses help prepare the body for physical action.

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