Feeling no pain

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(HOST) If you don’t expect something to hurt much, it may not. Research proves that the placebo effect is genuine, says commentator Ruth Page.

(PAGE) Remember the white queen in Alice in Wonderland?
She yelled when nothing had happened, ’cause she knew that shortly the pin on her shawl would prick her. She told Alice thus she wouldn’t have to react when she did get pricked. If you’ve ever seen a child crying when nothing has touched it, but it sees a nurse about to give it a shot, you understand the expectation of pain.

The opposite is also true: positive thinking, assuming the pinprick will be mild and not bothersome, helps to make it so. Researchers using magnetic resonance imaging learned that the same neural passageways in the brain that react to pain also react to the mere expectation of pain.

The researchers figure that’s why placebos often work. They reduce your expectation of pain, so when the nurse says,
“This will relieve your pain,” even a placebo often does.

Tests have shown the truth of this. Volunteers are given pulses that cause pain in a leg or arm and told they’ll feel some pulses
on their skin, some quite mild, some stronger, some more painful, though nothing damaging. Particpants are told to prepare for three levels. They understand that after seven seconds they’ll feel a mild pain jolt. After fifteen, they’ll feel a stronger one; and after 30 more seconds, one even stronger.

The pain came from heat pulses, none strong enough to discolor or damage the skin. A number of trials were done, as doctors varied the timing signals so that they didn’t always come in order. The 30-second one might be just moderate, for instance.Leaders of the study said that volunteers’ reports of feeling pain lessened by twenty-eight percent when people expected less pain, even if pulses were strong.

So brain pathways matched the expectation, not the actual degree of pain delivered. People often got mixed up about which pulse was stronger; thus the placebo effect was confirmed. Researchers said placebos reduced pain’s impact as much as morphine does. Our brain’s mechanisms work as much on what we expect as on what we feel. Is this true for all of us?

It may be that pessimists will make a tougher test. The research group has not yet tested that hypothesis, but it plans to do so. And are all doubters likely to be pessimists, or are some just natural-born skeptics? It will be interesting to see results from
the next batch of tests.

Pain, of course, is useful and necessary to many organisms. Many years ago I met a man whose nervous system didn’t work right: he couldn’t feel pain. He had to be aware of what he was doing every moment, or he could unwarily put his hand on a hot surface and get a serious burn. Remember, it’s the burnt child
who shuns the fire. Pain has its uses.

This is Ruth Page in Shelburne.

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