Impact of Mindfulness-Based Stress Reduction training on intrinsic brain connectivity

Abstract

The beneficial effects of mindful awareness and mindfulness meditation training on physical and psychological health are thought to be mediated in part through changes in underlying brain processes. Functional connectivity MRI (fcMRI) allows identification of functional networks in the brain. It has been used to examine state-dependent activity and is well suited for studying states such as meditation. We applied fcMRI to determine if Mindfulness-Based Stress Reduction (MBSR) training is effective in altering intrinsic connectivity networks (ICNs). Healthy women were randomly assigned to participate in an 8-week Mindfulness-Based Stress Reduction (MBSR) training course or an 8-week waiting period. After 8 weeks, fMRI data (1.5T) was acquired while subjects rested with eyes closed, with the instruction to pay attention to the sounds of the scanner environment. Group independent component analysis was performed to investigate training-related changes in functional connectivity. Significant MBSR-related differences in functional connectivity were found mainly in auditory/salience and medial visual networks. Relative to findings in the control group, MBSR subjects showed (1) increased functional connectivity within auditory and visual networks, (2) increased functional connectivity between auditory cortex and areas associated with attentional and self-referential processes, (3) stronger anticorrelation between auditory and visual cortex, and (4) stronger anticorrelation between visual cortex and areas associated with attentional and self-referential processes. These findings suggest that 8 weeks of mindfulness meditation training alters intrinsic functional connectivity in ways that may reflect a more consistent attentional focus, enhanced sensory processing, and reflective awareness of sensory experience.

Copyright © 2011 Elsevier Inc. All rights reserved.

Figures

Figure 1

Intrinsic connectivity networks identified by ICA: a) auditory/salience network; b) medial visual network; c) lateral visual network; d) sensorimotor network; e) default mode network; f) executive control network; g & h) frontal parietal networks.

Figure 2

Single group maps of the auditory/salience ICN for MBSR subjects (left panel) and wait list controls subjects (middle panel) are presented. In the right panel, significant group differences are shown; red indicates areas of significantly increased functional connectivity while blue indicates areas of greater anticorrelation with the auditory/salience ICN in MBSR subjects compared to wait list controls.

Figure 3

Single group maps of the medial visual ICN for MBSR subjects (left panel) and wait list controls subjects (middle panel) are presented. In the right panel, significant group differences are shown; red indicates areas of significantly increased functional connectivity while blue indicates areas of greater anticorrelation with the medial visual ICN in MBSR subjects compared to wait list controls.

Figure 4

Two regions in the anterior DMN displayed altered functional connectivity with sensory-related ICNs in MBSR subjects compared to controls. The red cluster (dmPFC) had increased functional connectivity with the auditory/salience ICN. The blue cluster (sACC) had greater anticorrelation with the medial visual ICN. The DMN across all subjects is outlined in dark grey.