Brain scans reveal mindfulness meditation for pain is not a placebo

Pain is a complex, multifaceted experience that is shaped by factors beyond physical sensations, such as a person’s mindset and expectations of pain. The placebo effect, a person’s tendency to improve symptoms in response to inactive treatment, is a common example of how expectations can significantly alter a person’s experience. Mindfulness meditation, which has been used for centuries in various cultures to manage pain, has long been thought to work by activating the placebo response. However, scientists have now shown that this is not the case.

A new one studypublished in Biological psychiatryhas revealed that mindfulness meditation uses different brain mechanisms to reduce pain compared to the placebo response. The study, conducted by researchers at the University of California San Diego School of Medicine, used advanced brain imaging techniques to compare the pain-reducing effects of mindfulness meditation, a placebo cream, and a “fake” mindfulness meditation in healthy participants.

The study found that mindfulness meditation led to significant reductions in pain intensity and pain unpleasantness ratings, as well as reduced brain activation patterns associated with pain and negative emotions. In contrast, the placebo cream only reduced the brain activation pattern associated with the placebo effect, without affecting the person’s underlying pain experience.

“The mind is extremely powerful, and we’re still working on understanding how to harness it for pain management,” said Fadel Zeidan, Ph.D., professor of anesthesiology and endowed professor of empathy and compassion research at the UC San Diego Sanford Institute for Empathy and Compassion. “By separating pain from the self and letting go of evaluative judgment, mindfulness meditation can directly change how we experience pain in a way that doesn’t use drugs, doesn’t cost anything, and can be practiced anywhere.”

The study involved 115 participants, consisting of two separate clinical trials of healthy participants, who were randomly assigned to receive four interventions: a guided mindfulness meditation, a sham mindfulness meditation consisting only of deep breathing, a placebo cream (Vaseline) that participants were trained to believe reduces pain, and a control group that listened to an audiobook. The researchers applied a very painful but harmless heat stimulus to the back of the leg and scanned the participants’ brains both before and after the interventions.

To analyze the participants’ brain activity patterns, the researchers used a novel approach called multivariate pattern analysis (MVPA), which uses machine learning to tease out the many complex neural mechanisms underlying the experience of pain, including those arising from specific heat stimuli, negative emotions, and pain responses driven by the placebo effect. The researchers were then able to identify whether mindfulness meditation and placebo engage similar and/or separate brain processes.

Although placebo cream and sham mindfulness meditation reduced pain, the researchers found that mindfulness meditation was significantly more effective at reducing pain compared to placebo cream, sham mindfulness meditation, and the control group.

They also found that mindfulness-based pain relief reduced synchrony between brain regions involved in introspection, self-awareness, and emotional regulation. These parts of the brain make up the neural pain signal (NPS), a documented pattern of brain activity thought to be common to pain across different individuals and different types of pain. In contrast, the placebo cream and sham mindfulness meditation showed no significant change in NPS compared to controls. Instead, these other interventions engaged entirely separate brain mechanisms with little overlap.

“It has long been assumed that the placebo effect overlaps with brain mechanisms activated by active treatments, but these results suggest that this may not be the case for pain,” Zeidan said. “Instead, these two brain responses are completely different, supporting the use of mindfulness meditation as a direct intervention for chronic pain rather than as a way to activate the placebo effect.”

In modern medicine, new therapies are generally considered effective and reliable if they outperform placebo. Since the current study showed that mindfulness meditation is more powerful than placebo and does not activate the same neurobiological processes as placebo, the findings have important implications for the development of new treatments for chronic pain. However, more research will be needed to demonstrate these effects in people living with chronic pain, as opposed to healthy participants.

In the long term, the researchers hope that by understanding the different brain mechanisms underlying mindfulness meditation, they can design more effective and accessible interventions that harness the power of mindfulness to reduce pain in people with a variety of health conditions.

“Millions of people live with chronic pain every day, and there may be more that these people can do to reduce their pain and improve their quality of life than we previously thought,” Zeidan said. “We are excited to continue exploring the neurobiology of mindfulness and how we can leverage this age-old practice in the clinic.”

Co-authors of the study are Gabriel Riegner and Jon Dean of the UC San Diego School of Medicine and Tor Wager of Dartmouth College.