Posted 04.25.2017 | by AMRA
Mindfulness training has been shown to improve performance on behavioral measures of executive control including attention, working memory, emotional and cognitive control, and decision making. Research also suggests that a brain region known as the dorsolateral prefrontal cortex (dlPFC) plays an important role in executive control, serving as the hub of an executive control brain network. The dlPFC has rich anatomical connections to other brain regions that are also thought to be involved in executive control. Does mindfulness training assist executive control by improving the way the dlPFC interrelates with these other brain regions?
One way to test this is by assessing resting state functional connectivity between the dlPFC and other brain regions. Resting state functional connectivity is a measure of how much different brain regions work in tandem. For example, when one region increases activity, other brain regions act in sync with it.
Taren et al. [Psychosomatic Medicine] tested whether mindfulness training increases the functional connectivity between the dlPFC and other executive control brain regions by comparing functional connectivity after either mindfulness training or relaxation training in a randomized, controlled study.
The researchers randomly assigned 35 unemployed, job-seeking adults (average age = 40; 57% male; 66% Caucasian) who reported high levels of stress to either an intensive 3-day residential mindfulness training, or an intensive 3-day residential relaxation training. Mindfulness training was a condensed version of Mindfulness-Based Stress Reduction that included body scanning, sitting, walking, and eating meditations, and mindful yoga. Relaxation training included resting while walking and stretching and didactic presentations, but did not include progressive muscle relaxation.
All participants underwent functional magnetic resonance imaging (fMRI) both at baseline and two weeks after training. The fMRI sessions included a five-minute period when participants passively viewed a nearly empty computer screen with just a cross in the center while neither relaxing nor meditating. Resting state functional connectivity was assessed during this period.
The results showed that mindfulness training increased functional connectivity between the dlPFC and five different brain regions associated with cognitive control (the left superior parietal lobule, right supplementary eye field, right middle frontal gyrus, right inferior frontal gyrus, and left middle temporal/angular gyrus) significantly more than did relaxation training. Mindfulness participants showed no relative decreases in functional connectivity between the dlPFC and any of the brain regions as compared to relaxation training participants.
Findings show that mindfulness training increases functional connectivity between the dlPFC and other specific brain regions involved in executive control. This contributes to our knowledge of how mindfulness may enhance attention, working memory and other executive control functions through increasing functional connections between brain regions.
Future research can determine whether there is a relationship between these functional changes and the structural differences reported in studies of long-term meditators. The study is limited by its failure to include behavioral measures of executive control to test if they varied with changes in functional connectivity.
Taren, A. A., Gianaros, P. J., Greco, C. M., Lindsay, E. K., Fairgrieve, A., Brown, K. W., . . . Marsland, A. L. (2017). Mindfulness meditation training and executive control network resting state functional connectivity: A randomized controlled trial.