# The Effects of Mindfulness on Brain Network Dynamics Following an Acute Stressor in a Population of Drinking Adults

## TL;DR

Mindfulness after stress shifts brain activity to a state linked with emotional regulation, while control participants remained in a state linked with rumination.

## Contribution

This study introduces a novel approach using dynamic brain state modeling to test and optimize mindfulness-based therapies.

## Key findings

- Mindfulness participants spent more time in brain states with increased salience network activity.
- Control participants spent more time in brain states with increased default mode network activity.
- Increased occupancy in salience network states was associated with lower perceived stress in control participants.

## Abstract

What are the main findings?
Participants that completed a guided mindfulness session following an acute stressor spent more time in a brain state in which the salience network was more active.Following an acute stressor, participants in the control group spent more time in brain states in which the default mode network was more active.

Participants that completed a guided mindfulness session following an acute stressor spent more time in a brain state in which the salience network was more active.

Following an acute stressor, participants in the control group spent more time in brain states in which the default mode network was more active.

What are the implications of the main findings?
Mindfulness may work to shift the brain out of states responsible for rumination and into a state that better supports emotional regulation and recovery following stress.This work offers a novel approach to testing and optimizing mindfulness-based therapies.

Mindfulness may work to shift the brain out of states responsible for rumination and into a state that better supports emotional regulation and recovery following stress.

This work offers a novel approach to testing and optimizing mindfulness-based therapies.

Background: Previous research has found that mindfulness-based techniques are beneficial for reducing stress in heavy-drinking individuals. However, the underlying neurobiology of these stress-reducing effects are unclear. Moreover, much of the research examining neurobiological correlates of mindfulness has used static functional connectivity, suggesting that brain activity goes unchanged for the entire length of an MRI scan. Methods: In the current study, we used a state-based dynamic functional connectivity model to examine brain states during either a 10 min mindfulness session or resting control that followed an individually tailored stress imagery task. Using a hidden semi-Markov model (HSMM), six brain states and the associated dynamics of state traversal were estimated for a population of moderate-to-heavy drinkers (N = 32). We modeled the 36 Schaefer atlas regions spanning the salience and default mode networks, and the HSMM characterized each state by its distinct multivariate pattern of activity and covariance structure. Group differences in dwell times, transition behavior, and overall state dynamics were evaluated using permutation tests and mixed-effects models. Results: Participants that experienced the mindfulness session had more transitions and longer time spent in states in which the salience network was more active. Participants assigned to the control group had more transitions and increased time spent in states in which nodes of the default mode network were more active. Moreover, for control participants, increased occupancy time to SN-dominant states was associated with lower perceived stress. Conclusions: Using HSMM provided a unique insight into network connectivity during mindful states; we believe it offers a novel approach to testing and optimizing mindful-based therapies.