Mindfulness meditation reduces stress by increasing brain connectivity between top-down executive control regions, according to a recent study published this July in Biological Psychiatry.
Mindfulness meditation is a form of meditation designed to develop the skill of paying attention to personal inner and outer experiences, by using acceptance, patience, and compassion. Training programs have been shown to reduce stress levels in stressed individuals, including in stress-related psychiatric and physical health illnesses.
Within the brain, mindfulness meditation has also been shown to influence the default mode network – an interconnected set of brain regions. This network is most commonly shown to be active when a person is daydreaming or their mind is wandering.
Evidence has suggested that mindfulness meditation training may increase default mode network connectivity within brain regions important in top-down executive control – especially the dorsolateral prefrontal cortex. These regions are important for a wide range of high-level processes, such as attention, planning, reasoning and cognitive flexibility. It is thought that this in turn improves emotion regulation, stress resilience, and stress-related health outcomes.
The study, led by David Creswell of Carnegie Mellon University, combined these findings to test whether mindfulness meditation training increases connectivity between the posterior cingulate cortex and the dorsolateral prefrontal cortex, and whether these changes lead to improvements in neurogenic inflammation (nerve swelling which can occur solely due to stress).
35 stressed job-seeking unemployed adults were randomly assigned to either a 3-day mindfulness meditation program or a relaxation training program. Participants completed a resting state functional magnetic resonance imaging (fMRI) scan before and after the program – this is used to evaluate connectivity between brain regions when a person is not performing a task. They also provided blood samples before, and 4 months after, the program – this was taken to measure for neurogenic inflammation changes (more specifically, they tested for interleukin-6, an established biomarker that is elevated in high-stress populations).
The results revealed that mindfulness meditation training increased resting state connectivity between the highlighted brain regions, whilst relaxation training did not. Furthermore, mindfulness meditation appeared to reduce neurogenic inflammation when measured after 4 months, whilst there were increases in the relaxation training group. Further analyses found that these changes to brain connectivity explained 30% of the overall mindfulness meditation training effects on neurogenic inflammation.
These findings provide the first evidence that mindfulness meditation training increases resting state connectivity between top-down executive control regions, highlighting an important mechanism through which it reduces stress levels in stressed individuals.
