Alterations in Resting-State Functional Connectivity Link Mindfulness Meditation With Reduced Interleukin-6: A Randomized Controlled Trial.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 27021514 · doi:10.1016/j.biopsych.2016.01.008
What was done
Thirty-five stressed, job-seeking unemployed adults were randomized to either a 3-day intensive residential mindfulness meditation program or a 3-day relaxation training program. Participants completed a 5-minute resting-state fMRI scan before and after the 3-day intervention to evaluate default mode network functional connectivity via posterior cingulate cortex seed-based analysis. Blood samples were collected at baseline and at 4-month follow-up to assay circulating interleukin-6 (IL-6).
What was found
Mindfulness meditation training significantly increased resting-state functional connectivity between the posterior cingulate cortex and the left dorsolateral prefrontal cortex (p < .05, corrected), whereas relaxation training did not. These connectivity alterations statistically mediated 30% of the overall effect of mindfulness training on reduced IL-6 at 4-month follow-up. Absolute baseline and post-intervention IL-6 numbers were not reported in the abstract.
Why it matters
This trial identifies a plausible neurobiological mechanism linking mindfulness meditation to reduced systemic inflammation, showing functional coupling between the default mode network and executive control regions.
Limits
The sample size was small (n = 35) and restricted to stressed, unemployed adults. The resting-state fMRI scan was short (5 minutes), only a single inflammatory marker (IL-6) was evaluated, and statistical mediation does not confirm direct biological causality.