Thursday, June 16, 2011

Meditation Works Through Brain to Soothe Pain

Meditation There is increasing interest in exploring nonpharmacologic and non-interventional approaches for the management of pain. According to a study reported in the Journal of Neuroscience, even a brief course in meditative techniques may significantly reduce a person's sensitivity to pain [Zeidan et al. 2011]. While there are considerable limitations in the research to date, meditation might be a viable and helpful adjunctive approach for almost any person with pain.

In the study, researchers — from the Wake Forest University School of Medicine in North Carolina and Marquette University in Wisconsin — applied a painful heat stimulus to the calves of 15 healthy men and women both before and after they attended four 20-minute mindfulness meditation training sessions during the course of 4 days. Meditating in the presence of the noxious heat stimulus significantly reduced pain unpleasantness by 57% and pain intensity ratings by 40%, on average.

Functional magnetic resonance imaging (fMRI) brain scans conducted during the pain experiments showed that meditation influenced a number of changes in how the participants' brains responded to pain. For example, meditation training reduced activity in the somatosensory cortex in an area corresponding to the calf, thereby dulling response to the painful heat stimulus. Reduced pain also was associated with thalamic deactivation, which may reflect a limbic gating mechanism that modulates communication between incoming pain signals and higher-level functions in the brain.

Furthermore, limbic areas of the brain responsible for maintaining focus and processing emotions and pain — eg, anterior cingulate cortex, orbitofrontal cortex, and anterior insula — were more active during meditation, and such activity was greatest in volunteers who reported the most reductions in pain. Together, these data indicate that meditation engages multiple brain mechanisms that favorably alter subjective perceptions of the pain experience.

COMMENTARY: The outcomes of this study by Zeidan et al. seem promising; however, it must be considered that it was an experiment examining responses to an acute pain stimulus in a small group of healthy subjects. The value of meditation for persons with chronic pain conditions needs further consideration.

In a published interview, one of the authors conceded that “real life” chronic pain is much more complex than in a laboratory, and it can involve trauma, depression, and other physical and mental processes. However, often there is a suffering aspect of pain, which can be the hardest part to treat and, at the least, mindfulness meditation may be helpful “medicine” for that problem.

This particular study used a type of meditation known as Shamatha, or "focused attention." As with other forms of mindfulness meditation, it involves learning how to observe what is going on in one's mind and body without judging, and while focusing on one's breathing or a chanted mantra.

According to Zeiden and colleagues, reductions in pain ratings were greater in their study than had been attained in similar trials involving placebo pills, hypnosis, and even morphine and other analgesics. An important aspect of the study was that significant results were achieved after just 80 minutes of meditation training. While long-term training might prove even more beneficial, it appears that some of the positive effects might be realized by average patients in a minimal amount of time.

It has long been believed that meditation helps relieve pain not by diminishing sensation but by helping people to consciously control their perceptions of pain. The fMRI brain scan results in this present study imply that mediation actually may change the nature of pain before it is perceived and also allows people to better self-manage it. The possible role of the various brain regions revealed in this study is not entirely new and was previously discussed in a Pain-Topics UPDDATE [here].

Overall, mindfulness meditation could be a practical and viable adjunctive therapy worth recommending for almost any persons with enduring pain. And, helpful resources for patients from the National Center for Complementary and Alternative Medicine (NCCAM) can be accessed at [here].

However, it also must be acknowledged that a report several years ago from the U.S. Agency for Healthcare Research and Quality [PDF here] concluded that many uncertainties still surround the practice of meditation for health purposes. Scientific research on this modality does not appear to have a common theoretical perspective and has been characterized by poor methodological quality, the report states. Future research on meditation practices must be more rigorous in the design and execution of studies and in the analysis and reporting of results.

REFERENCE: Zeidan F, Martucci KT, Kraft RA, Gordon NS, et al. Brain mechanisms supporting the modulation of pain by mindfulness meditation. J Neurosci. 2011;31(14):5540-5548 [abstract here].