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bioRxiv · 10.64898/2026.10.08.757789

Coupled neuro-fluid dynamics in human bioelectromagnetism

Popov, T.·Miller, G. A.
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Abstract

Electroencephalography (EEG) and magnetoencephalography (MEG) are widely interpreted as direct, non-invasive measures of neural population activity, assuming surrounding tissue and cerebrospinal fluid (CSF) act as passive volume conductors that distorts but do not contribute to signal generation. Using conductive-fluid phantom experiments, structural magnetic resonance imaging, and in vivo EEG and MEG recordings, the present report challenges this assumption. Mechanically driven conductive fluid generated structured, oscillatory, source-localizable electromagnetic signals resembling M/EEG in the absence of neural tissue, and interindividual differences in CSF volume systematically moderated M/EEG signal amplitude. These findings suggest that, at the scales accessed by invasive and non-invasive electrophysiology, electromagnetic and mechanical processes form a coupled system in which contributions of neural currents and fluid motion cannot readily be uniquely separated.

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Popov, T., Miller, G. A.. 2026-10-15. Coupled neuro-fluid dynamics in human bioelectromagnetism. https://doi.org/10.64898/2026.10.08.757789

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