Mindfulness seems to improve nearly every aspect of health -- but how? While mounting research has revealed many of the numerous physical and mental health benefits of mindfulness, little is known of the mechanisms underlying these positive changes.

"Many people are skeptical about whether there are helpful aspects of mindfulness meditation practices," Dr. David Creswell, a professor of psychology at the university and the study's lead author, told The Huffington Post. "We show that mindfulness meditation impacts measurable brain circuits more so than helpful relaxation practices, and that these brain circuit changes help us understand how mindfulness meditation improves health."

The researchers found that inflammation seems to be the key factor, as mindfulness reduces it by way of impacting changes in the brain's functional connectivity.

“[T]his new work sheds light into what mindfulness training is doing to the brain to produce these inflammatory health benefits,” Creswell said in a statement.

Chronic inflammation -- the long-term, runaway activation of the immune system's defense response, even in the absence of infection or injury -- is at the core of a host of health problems, including heart disease, diabetes, cancer, stroke, depression and Alzheimer's disease.

This new work sheds light into what mindfulness training is doing to the brain to produce these inflammatory health benefits." Dr. David Creswell of Carnegie Mellon University

The researchers recruited 35 stressed-out adult job-seekers, and asked half of the participants to complete an intensive three-day mindfulness meditation retreat program while the other half completed a three-day relaxation retreat program that did not have a mindfulness component.

The participants completed brain scans before and after the programs, and also provided blood samples before the programs and after a four-month follow-up.

The brain scans revealed that meditation increased functional connectivity between two brain areas that typically work in opposition: the default mode network (which is involved in mind-wandering and internal reflection) and the executive attention network (key to attention, planning and decision-making). Relaxation training, however, did not have this effect.

The blood samples showed that participants who underwent the mindfulness training had lower levels of Interleukin-6, a biomarker of inflammation, than those who did the relaxation retreat.

The researchers concluded that the changes in functional brain connectivity resulting from the mindfulness program seemed to help the brain manage stress (a known inflammation trigger), and therefore is responsible for the reduced levels of inflammation.

Why does it seem to be more beneficial than mere relaxation for managing stress? Creswell suggests that mindfulness may have a more lasting impact.

"Mindfulness meditation teaches participants how to be more open and attentive to their experiences, even difficult ones," Creswell said. "By contrast, relaxation approaches are good in the moment for making the body feel relaxed, but ... [they're] harder to translate when you are dealing with difficult stressors in your daily life."

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