Credit UC San Diego Health Sciences

Pain is a complex and multi-dimensional experience influenced by factors beyond just physical sensation, including a person’s mindset and their expectations of pain. The placebo effect, where symptoms improve in response to inactive treatment, demonstrates how expectations can significantly impact a person’s experience. Mindfulness meditation, which has been used for pain management in various cultures for centuries, was previously believed to work by triggering the placebo response. However, recent scientific findings have disproven this belief.

A recent study published in Biological Psychiatry discovered that mindfulness meditation activates specific brain mechanisms that differ from those involved in the placebo response, leading to a reduction in pain. Researchers at the University of California San Diego School of Medicine utilized advanced brain imaging methods to compare the pain-relieving effects of mindfulness meditation, a placebo cream, and a “sham” mindfulness meditation among healthy participants.

The research discovered that mindfulness meditation led to notable decreases in both the intensity and unpleasantness of pain, as well as a reduction in brain activity linked to pain and negative emotions. On the other hand, the placebo cream only affected brain activity related to the placebo effect without changing the person’s actual experience of pain.

“The mind is incredibly powerful, and we are still trying to understand how it can be used for managing pain,” said Fadel Zeidan, PhD, a professor of anesthesiology and Endowed Professor in Empathy and Compassion Research at UC San Diego Sanford Institute for Empathy and Compassion. “By separating pain from the self and letting go of judgment, mindfulness meditation can directly change how we experience pain. It does not involve any drugs, costs nothing, and can be practiced anywhere.”

The study involved 115 participants who took part in two separate clinical trials. The participants were randomly assigned to different groups to receive one of four interventions: guided mindfulness meditation, a sham mindfulness meditation involving only deep breathing, a placebo cream (petroleum jelly) that participants were told reduces pain, and, as a control, listening to an audiobook. The researchers applied a mildly painful but harmless heat stimulus to the back of the leg and scanned the participants’ brains before and after the interventions.

The researchers utilized a new method known as multivariate pattern analysis (MVPA) to examine the brain activity patterns of the participants. This method uses machine learning to understand the complex neural mechanisms linked to the sensation of pain. These mechanisms involve specific responses to heat stimuli, negative emotions, and pain reactions induced by the placebo effect. Using this approach, the researchers could ascertain whether mindfulness meditation and the placebo effect trigger similar or different brain processes.

Although both the placebo cream and sham mindfulness meditation reduced pain, the study revealed that mindfulness meditation was significantly more effective in pain reduction compared to the placebo cream, sham mindfulness meditation, and the controls.

They found that mindfulness-based pain relief reduced synchronization between brain areas involved in introspection, self-awareness, and emotional regulation. These areas of the brain make up the neural pain signal (NPS), a recognized pattern of brain activity associated with pain across different individuals and types of pain. On the other hand, the placebo cream and sham mindfulness meditation did not show a significant change in the NPS compared to the controls. Instead, these interventions engaged entirely separate brain mechanisms with little overlap.

“It has been widely believed that the placebo effect and the brain mechanisms activated by actual treatments are closely linked. However, these findings indicate that this may not be the case when it comes to pain,” explained Zeidan. “Instead, these two brain responses are entirely separate. This supports the idea of using mindfulness meditation as a direct treatment for chronic pain, rather than as a means of triggering the placebo effect.”

In modern medicine, new therapies are considered effective and reliable if they perform better than a placebo. A recent study discovered that mindfulness meditation is more effective than a placebo and does not activate the same neurobiological processes. These findings are significant for developing new treatments for chronic pain. However, further research is needed to confirm these effects in individuals with chronic pain as opposed to healthy participants.

The researchers aim to use their understanding of the specific brain mechanisms involved in mindfulness meditation to create better interventions. These interventions could be more effective and accessible and could help reduce pain in people with different health conditions.

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