Sunday, 27 July 2014

Legless in Kampuchea

Nearly 3 million people have tuned into TED to watch VS Ramachandran talk about the weirdness of how our brain makes sense of the world. A couple of them are me because I had occasion recently to cite the great neurologist for his thoughts on the intrinsic meaning of the sounds of language.  In the same talk (from about 9:30 minues), he refers to his extraordinary work on phantom limbs.  This is firm belief of amputees that the limb is still there.  They can feel it so clearly that all kinds of aspects of their lives are forced to accommodate something that isn't there.  That's what we do all the time, we try to make sense of the world and come up with rational narratives to explain random events that have happened to us.  It is too much to allow that shit happens - there must be a reason.  If you seed the idea that entirely ficticious events have happened to people - they went on a trip in a hot-air balloon as a child - they will not only come to firmly believe that it happened but invent all sorts of reasons why it happened - Uncle Jim was in town and took the kids for a treat etc.

That would be curious or mildly amusing except that a large proportion of amputees experience their limb as twisted in agony to such an extent that their quality of life falls through the basement into a hell which you and I can barely imagine.  Well, of course, everyone said, that's because you've sawed off the leg and the nerve endings including pain receptors are still raw and still transmitting.  So for years the standard treatment was pain-killing meds.  But Ramachandran and others have shown through a series of damn-clever experiments that the pain is not peripheral but generated in the brain as it tries to make sense of the fact that part of its familiar body is missing.  Motor signals sent to the missing part have no visible effect and the cognitive dissonance is interpreted as pain.  It is similar to the effect when our eyes tells us that the floor on the ferry is horizontal while our semi-circular canals are telling us that it is heaving about in a storm.  The result is queasiness or even what Australians call a technicolor yawn.

Clever experiments are all very well but the neurologists tried a creative therapy based on a low low tech appropriate technology.  They hid the stump behind a mirror in such a way that it looked to the patient like there were two mirror-symmetrical limbs available (situation normal, therefore).  A short course in training - telling the patient to move both limbs in synchrony creates a feeling of oh look my phantom limb is moving under my command. After a while - a matter of weeks - in some people the now under-central-command limb no longer feels painful. I guess the unfortunates who have lost both legs are beyond this therapy.

Ramachandran mentions the Iraq war as a source of missing limbs but you can finish the TED talk and reckon that this is just a quirky anomaly that affects a small part of the case load of this adventurous neurologist in California. California is a long way from Cambodia. But hey, if you want people without legs, then Cambodia is the place to be.  Three decades of war strewed the countryside with twice as many land-mines as people to step on them.  It was one of the places that exercised Princess Di before she died and also helped put in place the Ottawa Treaty which repudiated the manufacture, use or stock-piling of anti-personnel mines. It has been signed off by 150+ countries, so it should now just be a case of cleaning up the residual mines with a minimum of lost limbs and lost lives. There is a shorter list of countries that have a different way of dealing with land-mines - making money from them: why not check to see which side of the fence your own nation stands?  From a science and engineering viewpoint, landmines have been ingeniously improved over the last 60 years. Some clever engineer, for example, designed a feature that makes the explosive charge spring out of the earth to eye-level before filling the air with ball-bearings.

Anyway, that's our shame.  But I can strongly recommend that you take ten minutes out of your life to read the story of  Canadian wanderer Stephen Sumner. He lost his leg in a bicycle-car accident, screamed through several years of phantom pain, then cured himself in the parking lot of the store where he bought a mirror.  With his eyes shining with fervour rather welling up with tears he went off to Cambodia, designed a light-weight unbreakable therapeutic mirror, loaded his bike with samples and went off into the countryside. Whenever he saw someone missing a leg, he'd dumb-show his way through the way to put the pain behind. "I can’t believe no one else is doing this. It’s super-effective. I’d have thought there would be thousands of people riding around with mirrors, but there are not… What is wrong with people?”

Now what was I quoting?  "to know even one life has breathed easier because you have lived this is to have succeeded."  Hats off to Mr Sumner.  Or wave your prosthetic legs in the air: that will do as well.

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