Spatiotemporal source localization with new reweighted method: a simulation study

Abstract

Recently a smooth temporal activation model was introduced to include temporal a priori information for the spatiotemporal localization of EEG sources. The temporal and spatial smoothing constraints improved accuracy of reconstruction in noisy data, but the spatial resolution was relatively poor. We have investigated a novel approach where in addition to spatial and temporal smoothing constraints, we also apply a novel reweighting method to improve the spatiotemporal resolution. To evaluate our approach, we conducted a simulation study of the spatiotemporal reconstruction problem for synchronous and asynchronous sources in EEG. In one example, four separate regions where each region contained four synchronous sources that were asynchronous with respect to the other three regions were simulated, both in noise-free and noise-added situations. The results showed that all four regions are recoverable with our approach, at a higher spatiotemporal resolution than existing approaches.