Sunday, 13 April 2008

Heart & Soul: Additional comments

My post Heart & Soul triggered some interesting discussions in various places, which I've compiled here in case anyone has anything to add!

Over on Searchwarp I got the following response:
i think this was a well written, and interesting article, however, i have
listend to transplant patients on oprah, or larry king, whatever, and they seem
to have the same likes and desires and favorites as those who their transplants came from. things they didn't like or crave before.i don't think that needs to be explained, just simply accepted.we don't know why, but until we do, i don't think we can rule something out that we don't know whether or not it exists. thanks for sharing with us

Here's my response:

I'm glad you liked the article.

However, I'd have to disagree with the notion that we should just accept such things without explanation or questioning... the truth is worth searching for.

As to the people you've heard on Oprah and Larry King, the cynic in me would insist I point out that those people were on tv as a result of their perhaps self-interest is a factor in what they were saying... people do like to get their 5 minutes of fame!

Although I agree we shouldn't rule something out when we don't know whether or not it exists (when we are ignorant we cannot make a decision one way or the other), when we have no strong evidence for it and strong evidence that it is incompatible with our best understanding of reality its reasonable to say we DO know, beyond reasonable doubt based on available evidence, that it doesn't exist.

Of course, should new evidence come to light, that position would have to be reconsidered, but until that time the only reasonable conclusion is that it doesn't exist (or more accurately that it is so improbable that we can safely ignore it).But enough of my additional rambling...thanks for reading!

What worried me most about the comment was the notion that some things should just be accepted, not explained. This is potentially a very dangerous way of thinking - accepting things based on authority rather than evidence (explanation) is the root of today's global problem with clashing religious (and political) ideologies.

Another response to my original post directed me to an article on Fractal Memory. It was an interesting read, but to me seemed to be lacking in any scientific insight and indulging in the unsupported speculation and vague, imprecise mis-use of scientific terms that pseudoscientific articles are so found of, as well as conflating two very different types of memory.

Here's my response to it:

In response to your interesting discussion of fractal memory: It is a fact that genes contain information that determines behavioural traits, these traits being selected by natural selection just like other, more obvious, gene effects (like size, length of claws etc).

Genes that cause certain types of behaviour that turns out to be advantageous to the organism are likely to be passed into the next generation (as the organism is more likely to survive and reproduce due to its superior behavioural "programming").

The analogy of evolution being just a software update is false, as evolution has shaped the hardware and software together, with changes in both being genetically controlled and heritable.

However, the fact that large quantities of digital information is stored in genes has nothing to do with the storage of memories as commonly understood - the memories we lay down during our lives are stored in the brain and since they are not stored in our genetic code, these memories are not heritable - they are not passed on.

Thus using the term memory for both the "things we remember" and the heritable behavioural programming of our genes can lead to misunderstandings.

As our memories (in the common sense of the term) are not stored in our genes, they are not passed on to our children, and are not present in the rest of our bodies beyond the brain.

Genetic "memory" has no relevance to "past life memories" or "transplant memories", as it is a fundamentally different type of memory - genetic memory relates to instinctive behaviours, not to "learned" memories such as we lay down in our brains during our lives.

their counter-response was if anything even more full of unsupported speculation and nonsensical pseudoscience than the original article:

I think it is possible that 'relevant to survival' memories are stored and passed genetically via reproduction, hence adaptation, which I don't believe is all down to natural selection.

It is just the case that this type of memory is one we cannot access consciously, so yes in that regard it is a very different type of memory I am describing.

With regard to people who have had limb transplants taking on the original owners personality traits. If those traits are ones that would be passed through the genes via reproduction (we know we often inherit
character traits from our family regardless of what science says in that regard look at identical twins seperated at birth and some of their similarities) so if those traits are heritable then they are stored some where some how as memory and as the brain is not formed at conception, the only palce the memory can be transferred and stored is in the genes.

There were so many unsupported assertions and misunderstandings of biology and evolution in that short piece... I tried to clear some of them up in my response:

There is no evidence that memories laid down in life are somehow added to (stored in) our genetic code.

If it was true that our genetic code was altered during our lives to store memories gained during our life then this would be observable in studies. Studies of our genetic code have been done and have shown that there is no such change in our genetic code.

I'm not sure why you say that we often inherit character traits from our family "regardless of what science says in that regard" - science agrees completely on that!

Some character traits are passed down genetically, and some are passed down through upbringing. Behavioural tendencies and character traits (which are not the same thing as memories laid down during your lifetime) can be stored in genes just like other qualities (physical size, eye colour etc), but the vitally important point to note is that information is not added to an individual's genome during their lifetime and then passed on to the next generation.

Your genome when you die will be the same as it was when you were born.

Additionally, for what you are saying to be correct, even if our genetic code was constantly updated as we laid down new memories during our lives, if an organ was transferred to someone else that person's genome would have to change and incorporate some of the genetic information from the transplanted organ.

This does not happen - a person's genome doesn't change after an organ transplant.

There's more discussion of this subject over on here.

I find the subject of non-brain"organ memory" fascinating, but the evidence doesn't add up and those who believe that organ transplants also transfer memories and personality traits within the transplanted organ strike me as not having considered the other implications (such as memory loss after appendectomies for example) that would logically follow if memories and personality traits really were stored in all our organs.

But with pseudoscientific articles like Dr Danny Penman's 'Can we transplant a human soul?' being published in major newspapers, it isn't surprising that people have such ill-considered beliefs and such poor understanding of basic science.

For some interesting reading on genuine science relating to memory, take a look at these links:

Anaesthetic drug numbs memory

Deep Stimulation boosts memory (yes folks, the 'deep stimulation' refers to stimulation of the brain ;-) )

Scientists reverse memory loss

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