In The Antidote: Happiness for People Who Can’t Stand Positive Thinking (Kindle Locations 940-956), Oliver Burkeman discusses research about the effects of meditation on the brain’s subjective perception of pain:
[Fadel] Zeidan wanted to test the effects of meditation on people’s ability to endure physical pain, and so, with refreshing straightforwardness, he decided to hurt them. His research employed mild electric shocks – jolts that weren’t sufficient to be harmful, but that were powerful enough to make limbs twitch – and participants were asked to rank their subjective experience of the pain. Some then received three twenty-minute lessons in mindfulness meditation over the course of the next few days, showing them how to develop non-judgmental awareness of their thoughts, emotions, and sensations. When further electric shocks were administered, those who used the meditation techniques reported significantly reduced pain. (In a related experiment by Zeidan’s team, using brain scans and pain created by a hot plate, meditation appeared to lead to less pain for every participant, with the reductions ranging from 11 to 93 per cent.) A critic might counter that the meditation was merely providing a distraction, giving the participants something else to focus on – so Zeidan had another group perform a mathematics task while being shocked. Distraction did have some effect, but it was nowhere near as large as that of meditation. And the meditation lessons, unlike distraction, lowered pain levels even when participants didn’t actively meditate during the shocks.
‘It was kind of freaky for me,’ Zeidan said. ‘I was ramping at four to five hundred milliamps, and their arms would be jolting back and forth, because the current was stimulating a motor nerve.’ Yet still their pain assessments remained low. Meditation, Zeidan believes, ‘had taught them that distractions, feelings and emotions are momentary, [and] don’t require a label or judgment, because the moment is already over. With the meditation training, they would acknowledge the pain, they realise what it is, but they let it go. They learn to bring their attention back to the present.’ If you’ve ever gripped the arms of a dentist’s chair, in expectation of imminent agony that never actually arrives, you’ll know that a big part of the problem is attachment to thoughts about pain, the fear of its arrival, and the internal struggle to avoid it. In Zeidan’s laboratory, focusing non-attachedly on the experience of pain itself rendered the experience much less distressing.
The Secular Buddhist interviewed Zeidan and one of his coauthors, John McHaffie. The introducitons out of the way, Zeidan starts explaining the experiment in detail at the 10:42 mark. Their paper is online. It is called “Brain Mechanisms Supporting the Modulation of Pain by Mindfulness Meditation”.