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arXiv · 1809.03930

Localization of Brain Activity from EEG/MEG Using MV-PURE Framework

Tomasz Piotrowski·Jan Nikadon·Alexander Moiseev
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Abstract

We consider the problem of localization of sources of brain electrical activity from electroencephalographic (EEG) and magnetoencephalographic (MEG) measurements using spatial filtering techniques. We propose novel reduced-rank activity indices based on the minimum-variance pseudo-unbiased reduced-rank estimation (MV-PURE) framework. The main results of this paper establish the key unbiasedness property of the proposed indices and their higher spatial resolution compared with full-rank indices in challenging task of localizing closely positioned and possibly highly correlated sources, especially in low signal-to-noise regime. Numerical examples are provided to illustrate the practical applicability of the proposed activity indices using both simulated and real data.

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Tomasz Piotrowski, Jan Nikadon, Alexander Moiseev. 2018-09-11. Localization of Brain Activity from EEG/MEG Using MV-PURE Framework. https://doi.org/10.1016/j.bspc.2020.102243

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