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bioRxiv · 10.64898/2026.10.19.760024

Disentangling evoked and induced activity from single-trial neurophysiological time series

Ahola, O.·Haxel, L.·Ziemann, U.·Ilmoniemi, R.·Lioumis, P.
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Abstract

Evoked and induced responses are fundamental neurophysiological readouts in the development and assessment of treatments for disorders with impaired neural function. Distinguishing these responses is essential for interpreting single-trial variability, identifying the determinants of these responses, and enabling real-time probing of cortical responsiveness. However, because of dynamic overlap, separating evoked and induced activity remains unsolved at the single-trial level when instantaneous fluctuations of cortical responsiveness are of interest. We developed the Evoked-Ongoing/Induced Separator (EOIS), a framework for separating event-evoked, ongoing, and event-modulated induced activity from single-trial data. EOIS recovers evoked and ongoing/induced components by leveraging their distinct phase-consistency features in MEG and real-time EEG, enabling subject-agnostic single-trial time-series analysis and attribution of cortical response variability to specific components. By delivering component-resolved time series, EOIS enables biomarker refinement, pharmacodynamic readouts, and closed-loop neuromodulation, facilitating translational deployment across individuals and care settings.

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Ahola, O., Haxel, L., Ziemann, U., Ilmoniemi, R., Lioumis, P.. 2026-10-24. Disentangling evoked and induced activity from single-trial neurophysiological time series. https://doi.org/10.64898/2026.10.19.760024

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