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Our future, our universe, and other weighty topics

Saturday, February 25, 2017

Full Brain Swaps and Partial Brain Swaps: Would Either Prove the “Brain Storage of Memories” Dogma?

We have all been brain brainwashed.

We have been brainwashed into believing various unproven dogmas about the brain, including the idea that all our memories are stored in our brains. Scientists have not proven such dogmas. But they constantly assert such dogmas, so often that the average person is as unlikely to question them as the average person in North Korea is unlikely to question the constantly repeated assertion that his dictator is a brilliant genius.

Consider the dogma that all our memories are stored in our brains. When you recall something, your body does nothing to suggest that you are using your brain to retrieve the memory. If I retrieve an apple on my table, my body gives me two different signals that my arm is being used to retrieve the apple. The first is the sight of my hand grasping the apple, and the second is the feeling of the apple in my hand. But if I retrieve a memory of my childhood, my body does absolutely nothing to hint to me that my brain is being used to perform this retrieval. The memory could be stored locally in my soul, or in some mysterious external consciousness infrastructure unknown to us.

Even when we scan brains with medical devices such as MRI machines, when a person recalls something there is no convincing evidence that information is being loaded from a brain location. See here for a discussion of how such brains scans have been hyped enormously, with their meager results being exaggerated very much. A typical MRI scan of someone retrieving a memory will show something like a 1% variation from region to region in the brain, something that tells us basically nothing. 

We can imagine an experiment that might prove that memories are stored in brains. Some animal might be trained to learn some information. The animal's brain might then be dissected, and scientists might somehow attempt to retrieve information supposedly stored in the brain. If the scientists could retrieve very specific information that was unknown to them – such as an image that the animal had been fear-conditioned with – that might be proof that a memory was stored in a brain. No such experiment has ever been done.

Scientists have done some fancy memory experiments with mice using a technique called optogenetics. Although such experiments have been greatly hyped in the popular press, a close examination of them will show they do not live up to their hype, as discussed here. Such experiments do not prove that specific brain cells of mice store particular memories, and certainly do not prove that any human memories are stored in the brain.

One might claim that death is an experiment proving that our memories are stored in our brains, on the grounds that memories all die when the brain dies. But when a simple TV set stops working, that doesn't prove that the TV shows it displayed were stored in the TV. They were actually stored externally. Moreover, near-death experiences mean that we cannot conclusively claim that cessation of a person's brain activity means the end of his memories.

Is there any experiment with humans that might prove that memories are stored in brains? I can imagine a bizarre future experiment that might attempt to do such a thing. It would be an attempt to perform a brain swap.

Let us imagine some scientists who wanted to test whether swapping the brains of two humans might result in a complete transposition of their personalities and memories. The idea would be to swap the brains of two people, and see whether the body of the the first person was then occupied by someone claiming to be the second person, and the body of the second person occupied by someone claiming to be the first person.

We can imagine a news story describing such an experiment:

January 25, 2045: Scientists completed their controversial brain swap experiment, and things went exactly as predicted. The brain of the terminal cancer patient John Baker was swapped with the brain of the terminal cancer patient Eddy Hawkins. After the operation, the person with the body of John Baker claimed to be Eddy Hawkins, and the person with the body of Eddy Hawkins claimed to be John Baker.

No doubt if such a result were achieved, scientists would say it was decisive proof that memories are stored in brains. But it actually wouldn't be. Let's suppose that John Baker's memories are stored not in his brain but in a soul. Let's suppose that the memories of Eddy Hawkins are stored not in his brain but in his soul. Now suppose we swap the brains of John Baker and Eddy Hawkins. Until death a person's soul may be kind of anchored not to his whole body but only to his brain. So if we swap the brains of the two men, we may cause their souls to move into different bodies. Now after the brain swap, it might be that both the soul of Eddy Hawkins and his brain is now in the body of John Baker, and it might be that both the soul of John Baker and his brain is now in the body of Eddy Hawkins. Doing such a brain swap doesn't allow us to tell whether the memories of these men are stored in their brains or stored in their souls.

But let us imagine a different type of experiment – not a full brain swap but only a partial brain swap. It might be done on two terminal patients. First a complete inventory of both of their skills and memories might be made, by having them answer a long series of questions and fill out various standardized subject tests. Then a small part of their brains could be swapped. A small part of the first patient's brain might be replaced with a corresponding part from the second patient's brain, and that same part of the second patient's brain might be replaced with a similar part that had been removed from the first patient's brain. Then scientists might look for sudden losses or sudden additions in the memories of the two patients.

What might conceivably happen is something like this. After this partial brain swap, the first patient might still claim to be the same person he had always been. But he might claim that his memory had been changed. He might now be able to remember things he never knew before.

There are all kinds of weird possibilities. It might be that John Baker might remember his experiences between ages 5 and 20, and also remember his experiences between ages 30 and 60. But his memories of life between ages 20 and 30 might be the memories of Eddy Hawkins. Or it might be that John would no longer remember how to play the piano, but would now remember how to fix cars – knowledge that he had gained from Eddy Hawkins. Eddy, on the other hand, might no longer know how to fix cars, but might now know how to play the piano, something he had never previously known.

It would seem to be impossible to reconcile any results such as these with any theory that memories are stored in the soul. Given such results, you would finally have proof that memories are stored in the brain. 

partial brain swap
Hypothetical result of a partial brain swap

It is quite possible that such an experiment might be performed. But I doubt very much that it would produce results like those just described. As discussed here, scientists do not have any workable theory of how the brain could be storing memories that last for 50 years. The main theory of memory is that memories are stored in synapses. But there is a huge reason for doubting such a theory. Synapses are subject to rapid molecular turnover and structural turnover which make them unsuitable for storing memories lasting longer than a year.

If this partial brain swap experiment is ever done, I think it will not produce results showing a swapping of memories. I think we will one day be able to swap brain tissues between two people, but I think such an experiment will not actually result in a transfer of memories.

There are experiments such as these that could in theory verify the idea that our memories are stored in brains, but such experiments haven't been done. The claim that all our memories are stored in our brains is a dogmatic assertion not yet proven by either observations or experiments.  Near-death experiences, Lorber's cases of people with good memory but fractional brains, and the lack of a workable detailed theory of brain memory storage all suggest that such a dogma is not correct.  Another thing casting doubt on such a dogma is the very fact that we are able to instantaneously recall obscure facts and distant memories. Scientists have no explanation as to how a brain can do such a thing, which creates all kinds of "how could a brain know where to find the exact location where a memory was stored" explanatory problems discussed here.

Postscript: Some have claimed that Wilder Penfield's experiments show memories are stored in brains, but such claims are unwarranted. Penfield's experiments are described in the book The Human Mind Explained (page 132):

When this area [the temporal lobe] was stimulated, 40 out of about 1000 patients reported vivid flashbacks -- a fragment of a tune, a child calling, being in a room. All were marked by a dreamlike quality with no sense of time or location. He believed that this was evidence that our memories are stored in one place in a complete and recoverable form. Later researchers pointed out, however, that few of the patients recalled actual memories.  

A page online says Penfield "did not provide support for the claim that what was elicited was actually a memory and not a hallucination, fantasy or confabulation."

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