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What causes stress and anxiety and why we have two brains

Stress is the first defence mechanism the human race ever had

Once upon a time when the world was young and humans were Arboreal Fructivores (tree dwelling fruit eaters), the world was paradise.  We had virtually no natural enemies, plenty to eat, and all was well with the world.  Until climate change (remind you of anything?).

The forests and jungles shrunk and were replaced by grassy plains that eventually became deserts, there was overcrowding, something had to give.  So Evolution / God / Mother Nature, whatever you want to call it, was forced to make a choice.  Some species stayed in the trees (our primate relatives the chimpanzee and so on), and some took their luck on the ground.

It was a pretty chaotic and terrifying couple of million years.  We started changing to adapt to our new environment, but we had no natural defences – no thick skin, big claws, sharp teeth – why we didn’t even have the sense to run away from predators because we had just never had to do that before.

So we were given the first survival mechanism for the developing human race – the fight or flight response – or stress.

We developed our first, or 'old' brain -  an additional part of our brain called the limbic system, the 'Survival Brain' or the 'Emotional Brain’, which reacted to threats by releasing a potent cocktail of chemicals and hormones into our system (including adrenaline and cortisol) that ‘pumped’ us up and got us ready to stand and fight – or run like hell (or the other 'F' - freeze, shrink, don't make a sound and use avoidance, governed by the Vagus Nerve) .

It works exactly the same way to this very day.

But the world has changed, the emotional brain reacts to anything it perceives as threatening based on how we see or perceive the world.  This includes our environment, conflict with other humans, long standing issues causing anger, fear or other negative emotions.  In fact we overreact; the limbic brain reacts to everyday stressors as if it was a tiger about to jump on us.

But we don’t fight, or run (a reason why exercise is so good for alleviating stress as it uses up the excess nervous energy and produces Beta Endorphins).  A lot of the time those chemicals just build up and up in our bodies, some of them cross the blood/brain barrier and cause ‘fuzzy thinking’.  Stress builds up and up and can become anxiety which in turn can become depression.

We have a second brain -  a Rational Brain, the 'new brain'.  This is the temporal lobe that surrounds the emotional brain.  It communicates with the emotional brain and tries to keep it in check.

So why doesn’t it do its job?

The Rational Brain has to think to come up with a rational explanation or solution for what is going on, unlike the emotional brain that just gives of constant ‘knee-jerk’ reactions.  These can be to what’s going on ‘out there’ or what’s happening in our heads (i.e. worry).

The emotional brain does not have language or a very good idea of what’s it’s really like ‘out there’.  Perhaps it’s still seeing sabre toothed tigers and bears in the mouth of caves.

It also has a hair-trigger, particularly in those people who have a predisposition to worry or anxiety. As our levels of arousal go up we become more and more reactive and more and more sensitive to the slightest threat.

Because of that hair-trigger – the emotional brain, via the emotional regulator glands the Amygdala (two very small almond-shaped glands), sometimes ‘hijacks’ stimuli or thoughts away from the rational brain via the "Air traffic controller' (the Thalamus). 

What can result is a rage attack, a violent response, a panic attack or any number of disastrous cognitive and emotional consequences.

Here’s a good explanation of the process by Author Joshua Freedman*.

Hijacking of the Amygdala

This is what happens in your brain when you get really mad - or really anything!

Emotional brain

The routes from sensation to action are depicted in this image of the brain.

The journey begins with sensation -- in this case vision -- which is routed to the thalamus. The thalamus acts as "air traffic controller" to keep the signals moving. In a typical situation, the thalamus directs the impulse to the cortex -- in this case the visual cortex -- for processing. The cortex "thinks" about the impulse and makes sense. "Aha," it says, "this is an exclamation mark! It means I should get excited." That signal is then sent to the amygdala where a flood of peptides and hormones are released to create emotion and action. In what Daniel Goleman labeled "The Hijacking of the Amygdala," the thalamus has a different reaction.

Like any skilled air traffic controller, the thalamus can quickly react to potential threat. In that case, it bypasses the cortex -- the thinking brain -- and the signal goes straight to the amygdala. The amygdala can only react based on previously stored patterns.

Sometimes this kind of reaction can save our lives. More frequently it leads us to say something harmful, to escalate the situation, or even to violence.

To minimize the damage from hijacking, it is important to practice patterns which lead to de-escalation.

From that hijacked state, that condition where your brain is flooded with electro-chemicals, you still have options. You do not need to stay hijacked -- you still can choose actions. After all, the chemicals do not persist -- they will dissipate in three to six seconds.

What to do when you’re temped to let your amygdala get the better of you

TAKE A DEEP BREATH - COUNT TO THREE - TAKE A MENTAL STEP BACK - AND LET OUT THAT BREATH, SLOWLY  (before you say or do anything).  It lets the rational brain catch up and keeps you out of trouble. It takes about six seconds and that could make all the difference.

A lovely postscript

A young samurai comes to an old Zen master and asks him to explain Heaven and Hell. The Zen master tells him, “You’re a stupid young fool; you wouldn’t understand! Stop wasting my time!” The samurai draws his sword and yells, “You weak old man! Don't you realize I could kill you right now?” The Zen master responds, “That my son, is Hell”. The young samurai, realizing that he was just hijacked so much he was about to kill an old, defenseless, and wise man, drops his sword and says, ”Thank you! Thank you for showing me what Hell is!” The Zen master responds, “That my son, is Heaven."

*Joshua Freedman is one of the founders and the Chief Operating Officer of Six Seconds, The Emotional Intelligence Network.  Also read 'Emotional Intelligence' by Daniel Goleman or visit his page Official website of Daniel Goleman.

PS.  This is a re-edited version of the original article published in 2007.