How a placebo reduces pain: Scientists move closer to cause

Scientists are looking into why and how a placebo reduces pain. A placebo could be a sugar pill, or a saline injection – something with no discernible effects, and yet still have the same effect as a drug – depending on what the patient believes about what he or she is taking. This goes to show that belief is the drug- and our minds can work just as effectively as some medicines.

Here is the story, first reported by the Daily Mail.

Date: 3rd April 2010

Source: Daily Mail

“The placebo effect – a phenomenon where symptoms can improve simply if a patient believes they are being treated – has long been recognised.

And now scientists are a step closer to discovering why it happens.

A new study has shown that brain activity related to anticipation declines in individuals who believe they have been given painkillers, leading them to feel less pain – even though they had been given a placebo or dummy treatment.

Researchers hope the findings will pave the way for developing new drug-free treatments.

‘The results suggest that being told you are being treated reduces the anticipation of pain, and hence the sensation of pain,’ say researchers at the University of Manchester.

In the study, volunteers were exposed to a laser focused on one arm and designed to cause moderate levels of pain.

Half the patients were told they were having an anaesthetic cream – that was in fact a simple moisturiser – rubbed on to their skin.

The were then exposed to another blast of the laser, but unknown to the patients, the power had been reduced.

It was therefore less painful, but not because of the dummy anaesthetic.

The researchers also measured activity in the brain related to anticipation during the experiment.

When the experiment was repeated six weeks later, those who believed they had been given an anaesthetic cream in the earlier procedure rated their pain levels as lower than those who had not – both before and after the cream was applied…Read More