Author: Saurabh Bhaskar Shaw1,2,3, Yarden Levy4,5, Allison Mizzi4,5, Gabrielle Herman6, Margaret C McKinnon3,7,8, Jennifer J Heisz9, Suzanna Becker2,4,5
1 Department of Psychiatry, Western University, London, ON, Canada.
2 Vector Institute for Artificial Intelligence, Toronto, ON, Canada.
3 Homewood Research Institute, Guelph, ON, Canada.
4 Department of Psychology Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada.
5 Centre for Advanced Research in Experimental and Applied Linguistics (ARiEAL), Department of Linguistics and Languages, McMaster University, Hamilton, ON, Canada.
6 Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON, Canada.
7 Department of Psychiatry and Behavioural Neuroscience, McMaster University, Hamilton, ON, Canada.
8 Mood Disorders Program, St. Joseph's Healthcare, Hamilton, ON, Canada.
9 Department of Kinesiology, McMaster University, Hamilton, ON, Canada.
Conference/Journal: Front Hum Neurosci
Date published: 2022 Jun 14
Other: Volume ID: 16 , Pages: 838614 , Special Notes: doi: 10.3389/fnhum.2022.838614. , Word Count: 360
Lifestyle interventions such as exercise and mindfulness training have the potential to ameliorate mental health symptoms and restore dysregulated intrinsic connectivity network (ICN) dynamics, seen in many psychopathologies. Multiple lifestyle interventions, in combination, may interact synergistically for enhanced benefits. While the impacts of lifestyle interventions on subjective measures of mood are well-documented, their impacts on ICN dynamics are not well-established. In this study, we assessed the validity of EEG-derived measures of ICN dynamics as potential markers of mood disorders, by tracking ICN dynamics and mood symptoms through the course of a longitudinal exercise intervention. Specifically, we investigated the separate and combined effects of aerobic exercise and mindfulness-like neurofeedback training on task-linked ICN dynamics of the default mode network (DMN), central executive network (CEN), and salience network (SN). Participants were assigned pseudo-randomly into four experimental conditions-Control, Running, Neurofeedback, and Combined, performing the corresponding intervention for 16 sessions across 8 weeks. Intervention-linked changes in ICN dynamics were studied using EEG-based neuroimaging scans before and after the 8-week intervention, during which participants performed multiple blocks of autobiographical memory recall (AM) and working memory (WM) trials, designed to activate the DMN and CEN, respectively, and to activate the SN in conjunction with the task-appropriate network. The EEG-based features for classification of the three core networks had been identified in our prior research from simultaneously recorded EEG and fMRI during the same AM and WM tasks. We categorized participants as "responders" or "non-responders" based on whether the exercise intervention increased their aerobic capacity (VO2-max) (Running/Combined group), and/or neurofeedback increased the percentage time spent in the calm mindfulness state (Neurofeedback/Combined group). In responders, compared to each intervention alone, the combined exercise-neurofeedback intervention resulted in a more healthy CEN-SN synchrony pattern. Interestingly, non-responders to neurofeedback exhibited a maladaptive pattern of persistent, task-inappropriate DMN-SN synchrony which we speculate could be linked to depressive rumination. Furthermore, the CEN-SN synchrony at baseline predicted NFB response with up to 80% accuracy, demonstrating the potential utility of such network-based biomarkers in personalizing intervention plans.
Keywords: aerobic exercise; central executive network (CEN); default mode network (DMN); intrinsic connectivity networks (ICN); mindfulness; neurofeedback; salience network (SN); tri-network model.
PMID: 35774480 PMCID: PMC9237564 DOI: 10.3389/fnhum.2022.838614