high road/low road

Hi guys

How do you understand these two terms which appear in the text below:

 

It takes only 12 milliseconds, according to Ledoux, for the thalamus to process sensory input and signal the amygdala. He calls this emotional brain the “low road.” The high road, or the thinking brain, takes 30 to 40 milliseconds to process what is happening. The hippocampal memory center provides the context. “People have fear they don’t understand or can’t control because it is processed by the low road,” Ledoux says.

I understand. Thanks.

Thanks for your explanations Avangi!

It's really a pretty good sentence.  I don't think I can improve on it.

   << people are afraid of something they do not understand or control >>  No, I'd say it means they don't understand the fear   -   they can't control the fear.

You might say we have two different types of controls: conscious and unconscious.  The rate of our heartbeat is under very strict control, but it's completely unconscious.  There are very few of us who can command our hearts to speed up or slow down at will.  Breathing is a little bit different.  We normally don't think about it.  It automatically speeds up when we exercise.  But we can "hold our breath," or speed it up, or slow it down within certain limitations.

Fear is more like breathing.  We can consciously reason it out that a situation is dangerous.  We may be riding in a bus and notice that the driver has fallen asleep.  To a dog who is riding with us in the bus, this is not a dangerous situation because he's not able to think through the possible consequences.  But to us, it's terrifying, because we have knowledge and understanding of traffic fatalities, and we reason that we may not be able to act quickly enough to avert disaster.  The fear may be so intense that we freeze and are unable to act, or we may be able to cowboy up and get to the driver in time to save the lives of the riders.  In terms of your sentence, this would be an example of a fear which we do understand and can control.

On the other hand, if you're unfamiliar with life in the forest and are out hiking alone; and you come around a sharp bend in the trail to find yourself face-to-face with a large, ferocious bear, you may well poop your pants before you even realize what you're looking at (twelve milliseconds).  The dog who is accompanying you might react even faster.  This would be an example of a fear which you don't understand and can't control.

Your conscious mind may or may not come onboard and catch up to the situation.  And there may be other cases in which your conscious mind actually has no knowledge or understanding at all of what it is your unconscious body is afraid of.  In these cases, the situation (sensory information) and the resulting fear are processed solely by the "low road," and the "high road" never even figures it out.

  - A.

This is how I understand them. For similar events, the ear hears a sound, signal goes to brain, brain sends signal to mouth to voice.

Low road example: A person sneaked behind me and said "BOO!", I said "AH!" To analyse this, I would say-- How interesting! my mouth said "AH" and it was not from my intention. And the "AH" might not be English. It was some sound I dont believe it came from my brain. If I had been holding a cup of coffee, I would have spilled it. How interesting, my brain sent signal to jerk my hands, that was so "automatic".

High road example: A person walking towards me and said, "Hello". I replied "Hi". The ear heard "Hello", signal went to brain (high road), brain did many things, and send "Hi" to the mouth. For this example, now, scientists say it is not 100% high road.