Combined encephalography (OPM-EMEG project)

Fig 1. Scheme of source localization in case of combined EEG/MEG measurements

The OPM-EMEG project is devoted to the development of an encephalography system, based on a small number of optically pumped magnetometers (OPMs) combined with EEG. The aim is to develop a comparatively cheap EMEG system with the spatial resolution comparable to much more expensive conventional MEG-systems containing 100-500 sensors. The idea of the project is based on previously developed by the Skoltech’s group algorithms for processing the OPM-MEG and EEG data, including a set of methods for scalp-to-cortex extrapolation of the electric potential via a solution of the ill-posed Cauchy problem for the elliptic differential equation (see Fig. 4), and two-stage algorithm for the solution of the source localization problem for combined MEG/EEG measurements (see Fig.3).

Fig 2. Mapping the EEG data from scalp (left) to cortex (right)

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