PT  - JOURNAL ARTICLE
AU  - Ma, Yijia
AU  - Brown, Joshua A.
AU  - Chen, Chaowen
AU  - Ding, Mingzhou
AU  - Wu, Wei
AU  - Li, Wen
TI  - Alpha-Frequency Stimulation Enhances Synchronization of Alpha Oscillations with Default Mode Network Connectivity
AID  - 10.1523/ENEURO.0449-24.2025
DP  - 2025 Mar 01
TA  - eneuro
PG  - ENEURO.0449-24.2025
VI  - 12
IP  - 3
4099  - http://www.eneuro.org/content/12/3/ENEURO.0449-24.2025.short
4100  - http://www.eneuro.org/content/12/3/ENEURO.0449-24.2025.full
SO  - eNeuro2025 Mar 01; 12
AB  - Alpha (8–12 Hz) oscillations and default mode network (DMN) activity dominate the brain's intrinsic activity in the temporal and spatial domains, respectively. They are thought to play crucial roles in the spatiotemporal organization of the complex brain system. Relatedly, both have been implicated, often concurrently, in diverse neuropsychiatric disorders, with accruing electroencephalogram (EEG)/magnetoencephalogram and functional magnetic resonance imaging (fMRI) data linking these two neural activities both at rest and during key cognitive operations. Prominent theories and extant findings thus converge to suggest a mechanistic relationship between alpha oscillations and the DMN. Here, we leveraged simultaneous EEG–fMRI data acquired before and after alpha-frequency transcranial alternating current stimulation (α-tACS) and observed that α-tACS tightened the dynamic coupling between spontaneous fluctuations in alpha power and DMN connectivity (especially, in the posterior DMN, between the posterior cingulate cortex and the bilateral angular gyrus). In comparison, no significant changes were observed for temporal correlations between power in other oscillatory frequencies and connectivity in other major networks. These results thus suggest an inherent coupling between alpha and DMN activity in humans. Importantly, these findings highlight the efficacy of α-tACS in regulating the DMN, a clinically significant network that is challenging to target directly with noninvasive methods.