Mindfulness meditation training alters stress-related amygdala resting state functional connectivity: a randomized controlled trial

Abstract

Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n = 130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n = 35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects.

Trial registration: ClinicalTrials.gov NCT01628809.

Keywords: amygdala; cingulate; health; mindfulness; stress.

© The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Figures

Fig. 1.

CONSORT flowchart of participants retained at each stage of the Mindfulness Meditation Training RCT.

Fig. 2.

Discovery study (a, top left panel) Greater self-reported perceived stress on the PSS (item average) is associated with greater rsFC between right amygdala and subgenual ACC (P < 0.001). (a, top right panel) Scatterplot between perceived stress and right amygdala-sgACC rsFC parameter estimates (n = 130, R = −0.15). (b, bottom left panel) Greater self-reported perceived stress on the PSS (item average) is associated with greater rsFC between left amygdala and ACC (P < 0.001). (b, bottom right panel) Scatterplot between perceived stress and left amygdala-sgACC rsFC parameter estimates (n = 130, R = −0.101).

Fig. 3.

Mindfulness Meditation Training RCT. The left panel depicts the region of sgACC that showed decreased rsFC with right amygdala from before to after mindfulness meditation training (HEM) relative to relaxation training (HER) (P < 0.05, corrected for multiple comparisons). The right panel depicts the mean percent signal change for subgenual ACC cluster for the mindfulness (HEM) and relaxation (HER) training groups at each of the two time points (pre- and post-intervention). Error bars depict ± 1 standard error. Parameter estimates were extracted in SPM8 and plotted in a random effects mixed model conducted in SPSS.