Eastern forms of mindfulness meditation have become increasingly popular in the United States. These forms of meditation increase awareness by encouraging the practitioner to pay attention to sensations and to accept those sensations without judgment. These practices are designed to relax your mind and body through breath or a certain mantra: instead of moving away from uncomfortable sensations, you accept that sensation and bring focus your back to your breath or mantra. This ability to accept negative sensation can be useful in many facets of life, especially for those living with chronic pain, anxiety, or depression. People afflicted by these disorders are often told at some point in their treatment plan that they must learn to live with some degree of pain or anxiety, whether it be physical or psychological. But does the degree to which you accept negative sensation influence the degree to which you feel it? Recent studies indicate that this is indeed the case, and that neurological changes that occur during meditation may help explain why.

Chronic pain affects 10-25% of adults in the United States. Two thirds of those affected individuals report that pain has prevented them from working and has severely impacted their quality of life, and two thirds of the population living with chronic pain report that they have been experiencing chronic pain for more than five years. Furthermore, three quarters of those suffering from chronic pain are depressed, and a staggering 95% suffer from anxiety.

We currently have a range of methods to treat pain from opiates to surgery. Sometimes, some of these treatments can be limited in their effectiveness and do not fully treat patients.

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Understanding the way we perceive pain may lead to more effective treatments. As depicted in the image to the left, the mechanisms that allow us to perceive pain are relatively complex. First, sensory inputs come into an area of the brain called the somatosensory cortex, which maps sensory information from the body and allows for perception of things like touch, heat, and pain. Signals sent to the somatosensory cortex are then sent to another area of the brain, called the dorsolateral prefrontal cortex (DLPFC). It has been theorized that the DLPFC monitors stimuli from the external world, stores these experiences in our working memory, and governs what we pay attention to in the presence of competing stimuli. In other words, the DLPFC could “decide” how we process pain.

Recent studies have shown that patients with chronic back pain have lower cortical grey volumes in the DLPFC than subjects without chronic pain. “Grey matter” refers to cell bodies that process information while “white matter” refers to axon tracts, the cellular cables that transmit information. Higher cortical grey volume means that there are more healthy cells to perform neural computations.

When chronic back pain is treated effectively, cortical grey volume of the DLPFC increases. This suggests that there is less activity in the DLPFC when a patient is in pain, and the decrease in cortical grey volume could alter how pain is perceived.

The DLPFC is also involved in regulating attention: 18.7 % of pain patients complain that they have difficulty with attention, and fifty-four percent of chronic pain patients have complained of some cognitive impairment, which could also be a consequence of decreased cortical volume in the DLPFC. A decrease in activity in the DLPFC is often correlated with an increased intensity and unpleasantness of painful stimuli, suggesting that the DLPFC plays some top-down role in the perception of pain. Lower activity in the DLPFC could lead to a decrease in cortical grey volume of the region. In addition, the DLPFC is connected to the anterior cingulate cortex (ACC). Patients who suffer from chronic pain and its often associated depression often have less activity in the DLPFC and a more active ACC.

Since meditation focuses on accepting negative sensations and focusing attention elsewhere, the practice could be effective for those who experience chronic pain. While the sensation of pain arises from physiological components of the sensory nervous system, the perception of pain is heavily influenced by cognitive states and unique subjective experiences on the perception of pain.

Several studies have indicated that various types of meditation can diminish the perceived intensity and unpleasantry—and associated anxiety—of pain. Most studies use mindfulness meditation, a practice of Buddhist origin in which practitioners focus their attention on their breath. Patients can then monitor their attention and bring it back to their breath when it has wandered elsewhere.

How mindfulness meditation mitigates chronic pain has yet to be determined although scientists have found that mindfulness meditation leads to an increase in cortical volume in areas, including the prefrontal cortex, that process somatosensory, visual, auditory, and proprioceptive stimuli. The DLPFC, as stated earlier, is observed to be thinner in subjects experiencing chronic pain. The DLPFC has previously been linked to attentional processing in pain; however, these higher cortical functions and their control over pain have not been researched as extensively as has how the spinal and lower level brain controls pain.

Chronic pain severely decreases the quality of life for those who suffer from it by, among other symptoms, causing depression or anxiety. But because meditation has previously been shown to effectively treat anxiety in patients with generalized anxiety disorder, it is hoped meditation will also help pain patients cope with anxiety. Furthermore, one study has indicated that depression can be correlated with higher activity in the ACC and lower activity of the DLPFC, similar to what is observed in those living with chronic pain. Recovery from depression is associated with reciprocal changes in activity in the ACC and DLPFC, suggesting that those brain areas are involved in the development of and recovery from depression—and might also be instrumental in coping with chronic pain. Another study showed that those who recovered from chronic pain had decreased reciprocal coactivation of the DLPFC and the ACC, corresponding to reduced evaluative and emotional responses.

Currently, research suggests that we should think about top-down treatments for chronic pain when the better characterized—but often detrimental—bottom-up, conventional treatments, like taking prescription medications or surgery, fail. Meditation could change the way future pain is perceived: teaching patients how to perceive pain might open up new avenues for treatment. Through mindful meditation practices, patients who suffer from chronic pain can improve their quality of life and can increase their tolerance for pain.

Further Reading

Image Credit: Rob Ireton via flickr