The Flight or Fight Response

Flight or Fight

The body’s answer to challenge or danger is the Fight or Flight response

During pre-history, if we saw a saber-tooth-tiger, the Fight or Flight would ensure we could run like hell or fight for our lives. Nowadays, of course, we’re seldom in any actual danger.

Most of our threats today are situations which are merely demanding or frustrating.  Possible instances would be important challenges, such as the first day at a new job, being exposed to threat, being criticised, or struggling to meet unrealistic expectations we have for ourselves or those that others have for us.

Such is the power of the mind, even thinking about stressful events can set off the Fight or Flight response.  

All of us encounter possible stressors (causes of stress) in the course of our daily lives. But these threats aren’t to our life.  They are threats to our pride, prestige, self image, and job security. How each of these threats affect us will depend on how each individual perceives the situation, and how that person copes.

The stressors which cause the most harm don’t necessarily need to be major life changing events either. With the mind and body so closely linked it’s possible to set off the Fight or Flight with anticipatory emotions like impatience, anxiety, anger and worry. 

It’s the little things

This means it’s predominantly the energy we waste on trivial daily annoyances that have the largest impact on our health and well being. Things like being late for work, getting stuck in traffic, noise pollution, queues in supermarkets, irritation with family members, stuff like that.  All of these things, when allowed to get on top of us, can set off the Fight or Flight.

Any of them can produce the same nerve impulses and chemical reactions as being faced with a Saber-Tooth-Tiger and a genuine threat to our life.

Stress occurs when the hypothalamus receives ‘Action Stations!’ messages from various parts of the brain; and will instantly prepare the body for action in anticipation of the danger. 

When that action fails to take place (time after time), undischarged Fight or Flight chemicals and muscular tension build up to produce stress.

Reading the following details about exactly what occurs within our bodies when the Fight or Flight kicks off, it isn’t surprising that such stress can cause so many problems and psychosomatic disorders.

The biology of the Fight or Flight Response

Our story begins with the sense organs of sight or sound receiving, and passing on to the sensory cortex, signals from our surroundings.  The information received will be integrated with our memory and evaluated.

When the final evaluation is of a challenge or a threat the hypothalamus is activated.  In a fraction of a second, the hypothalamus sets off a string of bio-events within our bodies that enable us – in an instant – to Fight or Flight.

Adrenaline and noradrenaline are produced by the adrenal glands.  They increase heart rate, raise blood pressure, increase our blood sugar levels and speed up our metabolic rate.  They will also increase the performance of our reflexes and our sense organs.  Our pupils will dilate so we can see more effectively.

Thyroid hormones are produced by the thyroid gland.  These also increase the metabolic rate, increase the heart rate, raise blood pressure, and maximise our mental capabilities.

Cholesterol also increases the heart rate, which raises the blood pressure still further pumping the blood around the body faster.  It will also aid in blood clotting in the case of an injury, and boosts energy levels.

Cortisol is produced by the adrenal gland and is the body’s own steroid.  It helps prevent the body from suffering allergic reactions which could inhibit our breathing.  This is at the expense of our immune system though (which explains why prolonged stress can be blamed for so much illness).

Endorphins are the body’s own pain killers.  Their job is to prepare us for potential injury.

The lungs dilate and we breath faster so as to take in more oxygen.

The digestive system slows down, or ceases altogether to enable blood to be diverted to the muscles.  The mouth becomes dry due to the absence of saliva. Gastric juice production may increase (feeling of burning in the pit of the stomach).  In extreme cases involuntary emptying of the bowels or stomach can occur.  The bladder may also become loose.

Blood vessels close to the skin surface will constrict and the blood will thicken to prepare for possible injury.  Red blood cells flood the bloodstream, carrying more oxygen to the muscles.  We will also perspire to remove excess heat if required.

The muscles will tense and be ready to run or fight.

All production of sex hormones stops.

The liver releases sugar and fats into the bloodstream to provide fuel for quick energy.

The autonomic nervous system slows down or stop some body systems so as to save energy for any physical exertion that may be required.  This include the immune system!

All in all, quite a list of events. The initial stages of arousal will remain the same whether we are faced with a major or a minor challenge.  But under extreme, prolonged, or persistent pressure the body continues manufacturing more and more stress chemicals.  When this arousal continues the adrenal glands manufacture anti-inflammatory chemicals that simultaneously speed tissue repair while depressing the immune system.

If all these biological changes continue unabated the body will go on trying to adapt under ever increasing pressure. 

Eventually it will begin to break down.  Perhaps in small ways to start with.  But over time it can result in many psychosomatic illnesses.  It can increase the chances of anything from a common cold, to ulcers, asthma, high blood pressure, angina, and even heart attacks or cancer.

In short, too much stress (Fight or Flight response) can kill you.  Reason enough to take steps to controlling and minimising stress levels.  Our world doesn’t have Saber-Tooth monsters roaming around it trying to eat us anymore. We seldom need the Flight or Fight Response.

Our primary goal should always be to encourage the parasympathetic nervous system to reinstate homeostasis.

To you and me, that means chilling out about all the shit we have to deal with and focus on creating a calm state of mind and body.


©  2000. 2019  John Freeman