Watchmaker (continued)

Okay. The woman is now functionally blind but there's nothing wrong with her eyes. Her problem is that a part of her brain has been selectively killed off. This is important since at the same time a young neurophysiology MD was doing a study at that hospital that was focused on strokes. While this woman didn't have a stroke, her injury did match the description in the MDs grant so he had to interview and access her though he knew her injury was unsuitable for his purposes and would definitely skew his data. Unfortunately that's the way it is in science. You have to setup a study with a research hypothesis (and alternate hypothesis) and then let the chips fall as they may. Back to the story...

The MD asked her permission to interview her for his study--no doubt hoping she'd say no--and then ran a series of questions and tests by her. Since few if any of the questions had any relevance he ran the study by her quickly and probably a mite brusquely. At one point, to test for aphasia, he thrust a pencil at her and told her abruptly to try to grab it with her hand--I forget if it was the left one or the right one, no doubt the next test would have been the other hand but that wasn't going to get done that day. Keep in mind the woman is blind--but she unerringly grabbed the pencil. To the amazement of both herself and the MD. And this was repeatable but not at first. Her success required her to not be thinking about what she was doing--like when she was originally surprised by his barked out order to grab the pencil.

Here's where the connection to the Watchmaker comes in. Most people think of themselves as a neatly integrated package. I certainly do. Our minds are a smooth lovely entity, no burrs, rough edges, and unique in the Universe. I certainly think of my mind that way on a day-to-day basis. However that's not very accurate. Our minds reflect that organic brain underneath and that is a hodge-podge collection of barely integrated bits and pieces. A Rube Goldberg device of the highest order. LOL Or maybe "order" is a very inappropriate word here. This is well documented now but back when this study was done it came as quite a surprise. See what happened is that we see by two pathways. One is via the visual cortex, a part of the frontal lobes and quite connected to our cerebral cortex. To put it another way, we're consciously aware of what we see when it's processed via the visual cortex. However there's a second pathway--which isn't surprising since most of the critters on the planet don't have a cerebrum and they can see just fine--which is processed in the cerebellum where motor movement is also processed. This is the type of vision which is below the level of our consciousness and is used most dramatically in fast paced action. Anytime somebody throws something at you and says "think fast!" if you catch it you can thank your cerebellum--if you don't, well feel free to blame your cerebrum. It's the "smart" part of our brain but not the fastest kid on the block when it comes to being integrated with the physical part of our selves.

So this landmark case illustrated that when our "higher" parts of our brain were added, they were just laid on top of the existing structures and didn't supercede them. We're improved models of other critters, not anything new and unique. Not exactly what the Watchmaker hypothesis would prefer you to believe.

Some of the results of neurophys reseach can be very uncomfortable. Like anyone else, I prefer to believe that my mind is integrated and fairly unpeturbable. But studies on stroke victims who have lost function on very specialized parts of their brain have shown how false that impressinon of our minds is--and it's not a thought that I'm comfortable with! One chilling example is that we have a small part in our brain that allows us to realize that something we see or feel is part of our own body. If that area of the brain is damaged, we won't recognize our body parts as our own. This is a bilateral section of the brain so it'll only affect one side--the side opposite of the damaged section of the brain. In a bizarre twist, if you point out a body part on that side, say his arm, the patient will deny that the arm is his and the logical portion of his brain will try to invent an excuse for why it's there. Often it'll be something like "the arm is my brother's, he forgot it here". Scary stuff. It illustrates to just what an extent the cerebral cortex is a servant to the deeper and older structures of the brain. Reminds me of Henry Kissenger and the bombing of Cambodia for some reason.


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