One day, years ago, I was walking through the woods in East Tennessee and I saw a bear.

What that means, neurologically, is that my eyes collected data that one part of my brain

processed into an image that other parts of my brain recognized as a bear.

At that point, a primitive part of my brain called the amygdala got involved.

It's like a threat detector.

It controls the fight or flight response and is there to keep us from getting eaten

by bears or otherwise killed.

This particular bear was some distance away, mining its own business.

So my brain gave me a drop of adrenaline, just enough to make me a little more alert

and aware, and then I walked the other way.

But what if I'd surprised that bear?

What if it had been startled and angry and charging at me?

That would be terrified, anyone would.

The charging bear is an immediate lethal threat.

It's fight or flight, liver die.

Your brain is going to take that information.

All the data that says a bear is coming to kill you and routed to your amygdala.

Then your amygdala, your primitive lizard brain, is going to take over.

It'll tell your glands to release gushers of adrenaline and cortisol.

Your airways will expand so more oxygen can get into your blood and your heart will

be harder and faster to get that oxygen-rich blood to the muscles you'll need to run

away or stand and fight.

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