Characterizing Resting-State Brain Dynamics with Frequency-Resolved EEG Microstates: Parallel Analyses of Psilocybin Microdosing and Acute Inhaled DMT
bioRxiv Preprint Server May 5, 2026 Povilas Tarailis, Inga Griškova-bulanova preprint
Frequency-resolved EEG microstate analysis can detect changes in brain dynamics that broadband analysis misses. In two public datasets, psilocybin microdosing produced subtle, frequency-specific effects—reduced global field power and altered delta- and theta-band microstate parameters—without broadband spatiotemporal changes. Acute inhaled DMT caused broader alterations across broadband, delta, theta, and alpha activity, indicating more extensive reorganization. In both conditions, delta-band microstate C showed increased duration and microstate D decreased occurrence, though these overlaps should be interpreted cautiously due to differences in dose, route, and context. The findings suggest frequency-resolved analysis is useful for characterizing altered resting-state brain dynamics.