Fight or Flight

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Fight or Flight Response

The fight or flight response, also known as the acute stress response, is a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. It was first described by Walter Bradford Cannon in the early 20th century, as a theory that animals react to threats with a general discharge of the sympathetic nervous system. This response prepares the body for a rapid, immediate response to a dangerous situation, enabling either fighting the threat or fleeing to safety.

Mechanism[edit | edit source]

The fight or flight response is triggered by the release of hormones that prepare your body to either stay and deal with a threat or to run away to safety. The hypothalamus in the brain activates two systems: the adrenal-cortical system and the sympathetic nervous system. The activation of the sympathetic nervous system leads to the release of norepinephrine from the nerve endings and the secretion of adrenaline and to a lesser extent norepinephrine from the adrenal medulla. This results in an increase in heart rate, blood pressure, and breathing rate. After the danger has passed, it takes between 20 to 60 minutes for the body to return to its pre-arousal levels.

Effects[edit | edit source]

The fight or flight response can cause a wide range of physical and emotional effects, including:

  • Increased heart rate and blood pressure
  • Dilated pupils
  • Pale or flushed skin
  • Trembling
  • Dry mouth
  • Rapid breathing or shortness of breath
  • Feeling of dread or terror

These effects are all aimed at improving the body's ability to survive a threat. Physically, the body is prepared to either fight harder or run faster. Mentally, the focus sharpens, and the perception of pain can decrease, allowing for increased performance in critical situations.

Evolutionary Perspective[edit | edit source]

From an evolutionary perspective, the fight or flight response has played a crucial role in the survival of humans and other animals. It enables individuals to react swiftly to life-threatening situations. The physical changes that occur during the response were essential for the survival of our ancestors who faced immediate dangers, such as predators or other threats.

Modern Implications[edit | edit source]

In the modern world, the fight or flight response can still be beneficial in dangerous situations that require a quick reaction. However, chronic activation of this response, due to ongoing stress or threats that are not life-threatening, can lead to negative health effects. These include anxiety, depression, digestive problems, heart disease, sleep problems, weight gain, and memory and concentration impairment.

Management[edit | edit source]

Managing the fight or flight response in today's world involves identifying stress triggers and learning coping mechanisms. Techniques such as deep breathing, mindfulness meditation, and regular physical activity can help mitigate the effects of stress and reduce the frequency of the fight or flight response being triggered.

See Also[edit | edit source]

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Contributors: Prab R. Tumpati, MD