Wednesday, August 1, 2007

Is The Brain Really Necessary

“We do not think with our brains but we cannot think without them.” Mortimer Adler

New research not only supports this shocking claim by the greatest philosopher of the Twentieth Century, but actually goes beyond it to show that this may even be an understatement: indeed consciousness may not depend on your brain.

You have probably read of curiosities such as the well-publicized case of Phineas Gage a railroad worker who had a 3’ by 1.25” iron tamping rod accidentally shot through his brain. He recovered from the accident with little effect and no memory loss even after suffering the destruction of one frontal brain lobe and damage to the other. Okay, you say, amazing but he only lost his frontal lobes. He still had a lot of his brain left so I’m not convinced that it is possible to think without your brain.

How about more extreme cases? Scientific American in an article titled “Strange But True” May 2007 reports on a surgery known as a hemispherectomy, in which half of the brain, one entire hemisphere is removed. These surgeries are most commonly performed on patients who are in neurologically desperate situations such as massive tumors or extremely frequent uncontrollable seizures.

In a study of 111 children who underwent the surgery because of uncontrollable seizures 86% are now either seizure free or greatly improved. But even more surprisingly most suffered no memory loss or personality change. Another study of these patients found that they often improved academically. One even went on to become his state’s Chess Champion. However the outcomes are mixed, the younger the patient the better the recovery usually is. Most often there will be a substantial or total loss of arm movement and vision on the side of the body opposite the lost hemisphere. Language loss, if any, is often recovered regardless of which hemisphere is removed. Okay, you say that is even more amazing but these people still had half of their brains left.

The July 20, 2007 issue of Nature contains an article titled “The Man With a Hole in His Brain.” This is the story of a man named Lionel Feuilet, a French civil servant who was recently discovered to have about 80% of his entire brain missing. The discovery was made during a routine CT scan conducted on him following his complaint of weakness in his left leg. His brain tissue had been slowly replaced through the expansion of his cerebral ventricles by spinal fluid in a process of slow hydocephalicization. His doctors were very surprised that he was behaviorally normal, holding down a fairly mentally demanding job and raising a family.

Wow! You say 80% of the brain gone but still functioning normally - I’m surprised. It really is shocking that this is possible, but perhaps the remaining 20% is still doing everything.

Okay, then how about this one. Science magazine reported in “Is Your Brain Really Necessary” Vol. 210, December 12, 1980 a similar case. However, in this instance the person in question had received a First Class Honors degree in Mathematics from Sheffield University. After complaining of headaches he was given a CT scan. His doctors were shocked when the scan revealed that 95% of his brain, was missing, having been replaced by water. It was estimated that he only had about 1 millimeter of brain tissue left on the outer edge of his cranial cavity, barely enough to be detected in the scan. In effect his brain was literally missing. The article also discussed the fact that other such cases are out there but go undetected because the persons involved have no symptoms.

In all likelihood the mathematician from Sheffield is not the most extreme case in the world. It is very probable that there are a few people walking around right now completely oblivious to the fact that substantially more then 95% of their brain is missing and in effect have no brain.

Why This Is Important

One of the central claims of materialism is that the soul does not exist and that consciousness and all of the processes associated with thought and intellect are merely the result of biochemical activity in the brain. Destroy the brain and you destroy the conscious part of you. This argument is held to disprove the possible of life after death.

While it is true that damage to the brain (in some cases even minor damage) can have catastrophic and tragic consequences, the existence of the anomalies discussed above show examples of people with normal levels of cognitive function, who, for all practical purposes have no brain. This is very strong evidence against the materialist claim that consciousness is nothing but natural biochemical reactions. While it seems evident that the brain has a major role in cognitive functioning there is clearly more to consciousness than physiochemical processes.

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