The Wonders of Evolution

I know I've talked before about RadioLab on here. I was listening to another really interesting podcast today, so I thought I would share some info that I learned!

According to Robert Sapolski, a professor of biology at Stanford University, information travels through the brain in two ways. The example the host gave to illustrate these phenomena is the following: he's on the way to his best friend's house. He opens the front door. He sees he friend on the floor.... Then there's a split of processes.

The first process involves the visual cortex: light bounces off the body on the floor to your eye, that information travels through the optic nerve to brain, then down into the visual cortex, which turns dots to lines, lines to shapes, etc. This "local train" chugs deeper into brain, and then you consciously realize the image you're seeing, which is that your friend is dead.

The other process totally bypasses visual cortex stuff and goes directly to amygdala. The amygdala instantly tells heart to pound, tells the stomach muscles to clench, and makes tears flow. But the amazing thing is that you're still a couple seconds away from consciously understanding the image that you're seeing through your visual cortex.

What does all this mean? Your body knows what you're seeing before your brain does.

[As an aside:

Interestingly, this basic idea actually goes back to circa 1900 and the researcher William James. He researched using the idea of a bear attack. Imagine you're walking in the woods and you're attacked by a bear. You feel scared, right? James wanted to know what that feeling of fear was made of. He understood the process in three steps: 1) you see the bear; 2) your body responds; 3) you realize what you're seeing, so the feeling of fear kicks in. So if your body can't respond, he hypothesized, you won't feel fear. Everyone thought William James and his theory were crazy until....

Antonio Damasio, a neurologist and the Director of the Brain and Creativity Institute at USC, tried to prove that this was actually partially true. He studied paraplegics, and found that they feel less. Less fear, less joy, less of everything. Just less. Because their body can't respond the way a fully functional person's does. Weird.]

Now the really interesting stuff (and some more info from Robert Sapolski). Imagine a couple fighting. When the fight begins, the amygdalic (is that a word?) response systems (heart pounding, stomach tightening) kick in for both the man and the woman. And the systems turn on at about the same speed (2 seconds!). But. BUT! The system turns off more quickly in men than in women. At the point that a man thinks the fight is over, the woman's body is still tense, her heart is still racing, etc. So even if logic tells her that the issue is over, the lingering tenseness in her body tells her brain that it is not actually over. And as a response, her brain looks for something else to fill the void, some related problem to fight about.

Doesn't that explain a lot?