Split Brains and Souls

A poster on recently asked :

Care to post proof that human beings have no soul?

And here's my answer to that challenge:

It would be difficult to conclusively disprove the existence of immortal souls, but the odd side-effects experienced by patients after "split-brain surgery" rather strongly suggests that we don't have souls during our biological lifespan.

Here's an online game that describes the outcome of the "split-brain experiments" in detail.

But in a nutshell, it used to be that when patients were suffering from severe epileptic seizures that couldn't be controlled by the medications of the time, the measure of last resort was to surgically cut the nerve bundle connecting the left and right halves of the brain. (As far as I know, improved anti-seizure drugs have made such surgeries obsolete.)

Not only did "splitting" the brain in this way help to reduce the seizures, but many of these patients were able to recover relatively normal functionality in everyday life.

However, under certain artificial conditions devised by experimenting scientists, the split-brain patients occasionally showed some very odd symptoms, particularly relating to the way that their brains processed sensory input and language.

For instance, the patient might be presented with something as familiar as an apple, and recognize it as something that he enjoys eating, and perhaps also recognize that a red apple and a red shirt were the same color.

Yet upon being asked by the researchers, "What's the name of this thing you're looking at?" the patient would come up blank -- totally unable to retrieve from memory and pronounce the words "apple" or "red." And the cause of these weird side-effects was that the two halves of the brain were no longer able to share information directly.

Now, if the consciousness of a living human were really located in a supernatural soul that exists apart from the physical brain, wouldn't we expect that this soul could carry information across the millimeter gap between the left and right brain, even though the physical connection had been severed?

Of course, there remains the possibility that a supernatural agent like God could create a soul at the very moment when we die, and miraculously download all of our brain's stored memories and sense of self into this newly-made soul, so that our individual personalities could survive the death of the brain. I see no way to prove or disprove that.

(And incidentally, the effects experienced by patients after "split-brain surgery" also give us good reason to doubt that there is such a thing as telepathy.)

Labels: religion, science

posted by Throbert | 7/01/2008 09:37:00 PM |

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