switch doctoring

I have been fascinated by placebos ever since the late Pat Wall gave a talk about them at a symposium on consciousness in the early Nineties. It was very small and very select; the report of the procedings “costs”:http://www.bookworkz.com/education/psychology_special_topics/0471938661.html an astonishing $160, and I am atill not quite sure how I was smuggled in there. We had Dennett, Searle, Tom Nagel, Tony-Marcel-who-cannot-stop-talking, Nick Humphrey, Maggie Boden, Colin McGinn …

In any case, Wall gave a wonderful talk about placebos which cured me forever of the temptation to suppose that consciousness can be an epiphenomenon. The point is that placebos work only when people consciously and whole-heartedly believe in them. Then they produce changes in thebody’s working far below the level of consciousness. They don’t just remove pain. They remove inflammation. Placebo treatment of heart patients improves their performace on the treadmill.

One of the stories he told, which is now a classic, was of a doctor in the Korean War, who developed acute appendicitis during a surgical marathon and had his nurse inject him with morphine so he could go onworking before going onto the table himself. Only after his own surgery did he discover that they had run out of morphine, and she had shot him up with saline solution instead. Yet the pain had vanished completely, and he had been able to work for another two hours.

Now comes the most astonishing twist on this experiment, “from”:http://www.newscientist.com/channel/space/mg18524911.600 the _New Scientist._

bq.. DON’T try this at home. Several times a day, for several days, you induce pain in someone. You control the pain with morphine until the final day of the experiment, when you replace the morphine with saline solution. Guess what? The saline takes the pain away.

This is the placebo effect: somehow, sometimes, a whole lot of nothing can be very powerful. Except it’s not quite nothing. When Fabrizio Benedetti of the University of Turin in Italy carried out the above experiment, he added a final twist by adding naloxone, a drug that blocks the effects of morphine, to the saline. The shocking result? The pain-relieving power of saline solution disappeared.

p. Wall himself died of cancer, a few years back. “I talked to him(“God knows why this is not bylined to me”)”:http://www.guardian.co.uk/uk_news/story/0,,253148,00.html while he was in remission. The pain of cancer, he said, serves no useful purpose at all.

This entry was posted in Science without worms. Bookmark the permalink.

4 Responses to switch doctoring

  1. Rupert says:

    So many questions. I was going to ask if anyone had reported a placebo effect with faux-pharmaceuticals in recreational settings, but then remembered the useful phenomenon of the contact high. But perhaps that’s just polishing the mirror neurons.


  2. acb says:

    If your mother found you chopping out lines on your mirror neurons she would be very upset.

    I _think_ it shows that there are certain configurations our nervous systems can reach, to which we are mormally stimulated by drugs. But they can be reached without this stimulus.

    The point is that “configuration” here is quite literal. There are cells which will actually change shape depending on whether we feel certain pain or not — this busiess of changing shape is after all how molecules communicate. The Naloxone physically blocks these receptors. Hence the cells can’t adopt the require configuration. Hence, ouch!

  3. rupert says:

    Drug-enabled states accessible without the original enabler? Check…

    Molecules communicate by changing shape, but also by ion exchange and boring old mobile electrons. Multiple, apparently unconnected stimulations can trigger the same effect.

    We live in a deeply cross-coupled soup of interacting mechanisms, from the grossest of brain structures down through bundles of neurons, chemically and electrically mediated interfaces, cell structures and (if you’re feeling Penrosian) down into the quantum level. Into this soup we ladle further ingredients of experience, compounds and the rest of the universe as strained through the phenomenological firewall.

    No wonder it can be a little difficult to untangle cause and effect. Fun trying, though, and though it’s really arrogant of us to suppose we might – I suppose we might.


  4. colin says:

    Very fascinating — yet in some ways the effect of naloxone doesn’t surprise me in the slightist. Some process has to be happening up there to make these placebos have an effect. And it makes more sense that the brain uses the exact same pathways/processes to achieve this effect then for it to create whole new ones.

    As to Rupert’s question regarding recreational psychoactives, the placebo effect has been shown have an effect when people believed they were drinking alcohol (And I’m sure this happens with other substances too but I haven’t seen studies)

Comments are closed.