The Brain on Stress

Blog Article/Post Caveat (Read First Please: Click the Link)

The brain requires around two-tenths of a second just to understand simple visual stimuli, and another two-tenths of a second to command muscle to react. Reaction times have been studied and show that men have faster reaction times the women, athletes faster than non-athletes. The point of no return for actions are about a quarter of a second, the span where once your decision goes to action you are unable to stop. Given that quarter second  cutoff, the distance at which you might literally be able to ‘dodge a bullet’ is around 800 yards. You need a half second to act when you perceive such things, in general. Humans evolved in a world where nothing moved two thousand miles an hour, so there is no reason for the body to be able to counter such fast actions. 

Our amygdala can process auditory signals in fifteen milliseconds, about the time it takes a bullet to go thirty feet. The amygdala triggers reflex actions and then waits for the conscious mind to catch up. That reaction is called the startle, and is composed of protective moves that would be a good idea in almost any situation. 

When something scary happens, every person does exactly the same thing, they blink, crouch, bend their arms, and clench their fists. The face sets into a fear grimace: pupils dilate, eyes widen, brows go up, and the mouth pulls back and down. 

The amygdala only needs a single negative experience to decide that something is a threat. When you act or react: pulse and blood pressure to heart attack levels, epinephrine and norepinephrine levels go through the roof, blood drains out of the organs and flood the heart, brain and major muscle groups. 

In truth, such violence does extraordinarily violent things to the human body (adrenal stress conditions) but actions to combat such violence requires almost dead calm to execute well. 145 BPM  ruins ability to aim well; 170 bpm’s you get tunnel vision, loss of depth perception, and restricted hearing; 180 bpm you enter a netherworld where rational thought decays, bowel and bladder control are lost, and you start to exhibit crude survival behaviors such as freezing, fleeing, and submission. 

Cortisol, secreted by our adrenal gland during times of stress that sharpen our minds and increase our concentration ability. I wonder just how one could cause a release of cortisol in times of stress or just before entering into high stress situations such as combat, etc.? 

Bibliography:

Junger, Sebastian. “War.” Hachette Book Group. New York. 2010.