PCC-hippocampal functional connectivity associated with stress biomarker changes after meditation training for healthy adults.

Meditation training has been shown to improve physical and mental health and promote neural plasticity, but more research is needed on the relationships between these effects. This study analyzed the Resting State Functional Connectivity (RSFC) of posterior cingulate cortex (PCC) among 94 chronically stressed but otherwise healthy adults randomized 1:1:1 to receive eight weeks of in-person one-on-one interventions focused either on meditation (n = 32), yoga (n = 31), or stress education (n = 31). We found only in the meditation arm, there was a significant reduction of PCC RSFC with the left hippocampus (p < 0.05, FWE corrected). Post-intervention changes of PCC-hippocampal RSFC were significantly (all p ≤ 0.01) correlated with changes of perceived stress (r = 0.54), allostatic load index (r = 0.58), and NF-κB anti-inflammatory gene expression (r = -0.55), suggesting the neural effects of meditation are closely associated with biomarkers of physical wellness. No significant changes with PCC RSFC were observed within the yoga or stress education arm, suggesting this neurobiological mechanism might be unique to meditation training.