Tuesday, June 27, 2006

Plausible explanations

Scientific experiments, when succesful in producing statistically significant results, only answer the question that was asked, which usually is of the yes/no -type. Interpretation of the results is always up to the researcher. And researchers might interpret things in orthogonally different ways, depending on their background theories (or lack thereof). When an experiment produces an effect, it is often debatable what causes the effect, or what conclusions can now be drawn based on the verified existence of that effect.

A good example of very bad interpretation was demonstrated yesterday in the documentary on Channel 4. (Yes, I know, shouldn't watch C4, it's rubbish). They "investigated" the possibility that in heart transplants, part of the personality of the donor could be transplanted along the organ. This was backed up by a number of heart transplant patients whose personality had underwent a change as a result of the transplant, and their newly acquired traits were akin to those of the donors of their new hearts. In addition to the testimonies, they had some wacky Californian "scientists" explaining how there are neurons in the heart and that the network of these neurons is complex and it exhibits memory, and that's where these personality traits can travel from one person to another.

Where to start... Well, first of all, I think that organ donations should always be anonymous. In these cases, there has been mutual consent to reveal the identities of the donor and the recipient, which had then in some cases led to very emotional "let me listen to my brother's heart beating one more time" -kinds of things. This might help dealing with the loss of a relative or might be detrimental for both parties. One of the relatives of a donor who died in a stunt accident in his twenties, said he has found it easier to accept the loss now that he sees that the receiver had started doing sports and being very active, and was "making the most out of his new life". Imagine the pressure this puts on the shoulders of the recipient!

Second, I think nobody denies that a heart transplant is a life-changing event. To such an extent that it can affect your personality in many ways. People often see it as giving them a second life, so they might take up hobbies they didn't have before, or they might show a different side of their personality etc. And, often these new sides are more active, more creative, more open and agreeable than the old ones. Or feel like it for those around. Remember, the transplant is a trauma and a psychologically heavy process for the recipients' family and friends, as well. These active, creative traits are also exactly the kinds of things you tend to (want to) remember of your deceased relative. Bring the two together and you have a match.

If you take up sports after your heart transplant, it is not a surprise. It is more than likely as well, that your donor was an active sporty person, as a donated organs need to be healthy (no fatty couch potatoes dying of angina pectoris) and the donors often have died in accidents (active lifestyle, higher risk). Correlation, yes; causation, no.

Third, the neurons in the heart and them "remembering". Of course, we've known this for long. That's what keeps the heart pumping. There has to be memory in the neural network, of the previous cycles of oscillation, so that the next one can follow, and that there is stability in the system. That's all it does, however. Memory to sustain oscillation is different from memory about places, names or skills, such as poetry. Of course, our mind-body is a complex system, our cognition is embodied (I'm the first person to admit that, as it's a central tenet in my thesis), but before saying that since heart has neurons, it carries a part of our personality, you need to establish that there are sufficient, functionally relevant links between the brain (the parts we know are responsible for components of personality) and the "brain of the heart", as they called it. There are links, as both link to the same nervous system, but so do toes and all our muscles. While the neurons in the heart are like the ones in brain, functionally the connections between the two are more like the ones between brain and other internal organs or muscles than those between different regions and structures in the actual brain.

Finally, this connection between heart and the brain was what they told they were showing when they presented some experiments byt these wacky scientists. They had measured people's reactions to emotional stimuli and saw that the heart and the brain both react to them, and the heart anticipates some of the reactions. No news here: we have primary emotions that work pretty directly from perception to physical reaction (happiness, sadness, fear, anger), without needing any cortical processing. This concsious processing will then follow, leading to feelings. Evolutionarily it has been important to be able to prepare for fight or flight as quickly as the threatening stimulus occurs, without having to pause to think. We startle when we hear loud noises, for example. Our heart rate shoots up, hormones are released, muscles get ready to action etc. Again, showing this correlation is not enough to conclude that we "feel emotions with our heart and part of our personality lies there". Personality and these autonomic reactions are two very different things.

With this kind of an experiment, a "mainstream scientist" would take the results and talk about the experience of emotions and the embodied nature of cognition, and how the interlinkage between the autonomous nervous system and cognition are linked functionally and how there seems to be two pathways of processing emotionally valenced stimulus. In his/her case, the experiment has shed light on the issue and provided data based on which theories can be developed and better models built.

The wacky one would claim how he has now shown that heart thinks on its own and how the connection is so mysterious and magical that all previous knowledge about how we think is now invalid and transplanting hearts is probably bad and how it's all so new age. Muddying the waters, that is, and raising himself to a position of superior knowledge (while deciding what colour Porsche he should buy when the book advance arrives).

Lack of proper controls, relying on apparent coincidences, asking impossible questions, over-interpreting the experimental evidence and mystifying rather than clarifying are the telltale signs of bogus science. Check, check, check, MindShock ticked all the boxes!

(Pic: kzone.com.au)

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