Lead Field Space Projection for Spatiotemporal Imaging of Independent Brain Activities

Abstract

Magnetoencephalography and electroencephalography are non-invasive instruments that can record magnetic fields and scalp potentials, respectively, induced from neuronal activities. The recordings are, superimposed signals contributed from the whole brain. Independent component analysis (ICA) can provide a way of decomposition by maximizing, the mutual independence of separated components. Beyond the temporal profile and topography provided by ICA, this work aims to estimate and map the cortical source distribution for each component. The proposed method first constructs a source space using lead field vectors for vertices on the cortical surface. By projecting the specified components to this source space, our method provides the corresponding spatiotemporal maps for these independent brain activities. Experiments using simulated brain activities clearly demonstrate the effectiveness and accuracy of the proposed method.