Resting-state EEG biomarkers of accelerated intermittent theta burst stimulation treatment for depression: a pilot study

Accelerated intermittent theta burst stimulation (aiTBS) is a novel and effective treatment for drug-resistant depression. While past studies have identified encephalography (EEG) features predicting repetitive transcranial magnetic stimulation (rTMS) outcomes, EEG biomarkers specifically for aiTBS in depression patients have not been explored. In this pilot trial on 5 depression patients undergoing aiTBS, we assessed clinical outcome using the Montgomery-Asberg Depression Rating Scale (MADRS) and collected resting-state EEG pre and post-treatment. All patients showed an improvement in MADRS, with 3 having at least 50% improvement. We found significant correlations between MADRS change and pre-treatment frontal beta power, midline frontal Lempel-Ziv Complexity (LZC) and alpha connectivity. We also observed a trend of increased frontal theta power post-treatment. However, no significant correlations emerged between MADRS change and change in EEG feature post-treatment. This preliminary trial highlights the potential for investigating aiTBS-specific EEG biomarkers, paving the way for larger studies to enhance personalized neurostimulation and predict treatment outcomes in drug-resistant depression patients.