Tuesday, June 27, 2006

Mindshock: Transplanting memories?

I wonder if anyone saw this programme on Channel 4 last night. It reported a controversial theory that the heart may play a role in forming emotions, personalities and memories, based on the experiences of some heart transplant patients. This radical possibility clearly challenges the conventional textbook account of the heart as just a pump, and embraces the metaphorical vision of the heart which has featured in literature and the arts for centuries. The first person to report this was a heart transplant recipient in Boston twenty years ago who reported a sudden penchant for beer, green peppers and KFC nuggets, later found to be firm favourites of her young male donor. Strict confidentiality regulations meant that she could not have had access to this information, nor the name of her donor which she correctly gleaned from a dream.

However I wasn’t entirely convinced by some of the cases. One transplant patient who developed a love of classical music was found to have received a heart from an American violin-playing teenager. I couldn’t help feeling that if the recipient had developed an interest in hip hop or rock, this too could have resonated with the donor’s musical interests. Another placid woman received the heart of a boxer, and subsequently reported violent tendencies. Again, it seems far too convenient to attribute this simply to the stereotype of a violent boxer. A particularly fanciful example was a man who became a prolific writer of poetry, only to receive a letter from his donor’s family containing lines of verse.

One thing seems apparent; the quagmire of confounding factors. Clearly a major medical procedure such as a heart transplant is likely to induce a degree of introspection and promote some lifestyle changes. Perhaps just the notion itself of having a heart transplant is sufficient to drive changes in personality, just as surviving a car crash may be life affirming for some, or traumatic for others. The effects of immunosuppressive medication in altering moods have also been implicated. However, this may not explain all of the reports, nor the finding that in a blinded study of 70 transplant patients that felt a change in personality, 10 matched their donors’ closely. The discovery of neuronal populations in the heart has also led to talk of a ‘little brain’ and ‘heart intelligence’, and the possibility that some memories may be stored in the heart. The last word finally went to a Prof Paul Pearsall, one of the strongest proponents of a sentient heart. Seemingly bursting from the pressure of keeping a lid on the puns for the last hour or so, he finally succumbs: ‘We better wake up and have a heart’.

5 comments:

Unknown said...

Welcome to the blog Roshan, and thank you for such an interesting post. This issue reminded me of a case study written up in 'The Golem: what you should know about science' by Harry Collins and Trevor Pinch. Using some rather disgusting experiments which involved 'training'worms and then feeding them to other worms, McConnell and Ungar sought to show that memory was chemical instead of neurological. The work they did was never disproved and seemed to show that memory was chemically transferable.

Physicists seem to be able to get away with inventing new particles to explain peculiar results, but I think biologists will have a more onerous burden of proof -- for something to exert such a profound effect it would probably have to be big enough to be visible under a microscope.

Anonymous said...

Obviously this is a hypothesis that has some distance to travel before becoming generally accepted, but the evidence I think is strong enough to resist summary dismissal. It did feel nevertheless like a science fiction tale, and all the more intriguing for that. Let's see how far it can go.

One question I would want to ask is whether the discovery of a neuronal network in the heart might lead cardiologists to investigate the possibility of detrimental effects on the neurons through the use of defibrillators. This could be investigated independently of the question about distributed memories, although it may also contribute some pertinent data to the debate.

aj said...

Fortunately this program was repeated last week. I found the idea interesting, and certainly it wasn't something I'd heard of before. But what started out as a plausible idea did slip in the second half of the program into unfounded anecdotal evidence, and became slightly repetitive.

Some of the stories are undeniably remarkable, and I don't think the simple explanations of the effects of the immunosuppressive medications and the emotion of the circumstance are enough to cover the phenomenon.

However, the program made me think about organ donation, and my own personal feelings about it. Would you be comfortable with your personality showing through in your recipient? Or is it irrelevant, given the enormity of the action? Witnessing the strength of bond between the child donor's mother and the Cystic Fibrosis sufferer recipient was quite touching.

Anonymous said...

Don't forget that the transplanted heart is denervated by the fact of being transplanted... so there are no neuronal connections between the heart and the recipient body. Control of the heart to adjust heart rate and contractility to meet demand has to be purely hormonal.

10 out of 70 personality changes match the donor, eh? I can't begin to tell you how sceptical I am of this. How many "personality types" are there? What is the chance of any randomly-adopted personality type being the same as the donor's? Probably quite high, as much as 1 in 7 or 15%, quite possibly.
Look at Myers-Briggs Type Indicators descriptions some time - they are 16 "personality types" defined along four axes, and the descriptions they give for each of the 16 personality types pretty much fits anyone at times.
My point is that if you sat and wrote a description of the donor's personality, you could probably make most people fit it to some extent at some times, and some people (maybe even 1 in 7) would fit it very well.

Also, there is the additional factor of selection bias - it's like horoscopes - you remember the "hits" and forget the "misses".

I don't believe this, not the basis of the evidence advanced so far.

corneilius said...

I watched this and found it really clicked with what I sense - that there's an innate natural intelligence that is able to asses/read 'others' really quickly... it fits with my theory that the discovery of plant qualities by indigneous peoples by trial and error as proposed by western conventional wisdom would be in most cases catastrophically unsuccessful.

The theory about the heart as a cognitive elctromagnetic reader/transmitter is a much better explanation of how creatures in nature are so well integrated into their worlds, how they work so well together. How do dogs know what plants to eat when they are unwell?

I have always felt that being limited to the rational mind is not proven as a working tool in nature - that practically every european 'expedition' depended upon the locals to survive shows how unable to survive we were..

The heart math institute http://www.heartmath.org has done some really interesting work on this. Worth a visit.