Abstract
We investigated the EEG connectivity to visualize brain functional network. We employed a cross-correlation to analyze the connectivity of electrical activity. The electrical activity inside of the brain was estimated by solving the inverse problem of cortical dipole imaging. A threshold was established for the signal amplitude to extract major brain activity. Time-lag in the case of maximum correlation coefficient between observation points was calculated to visualize propagation path of the brain signal. The proposed method was applied to visual evoked potential of checkerboard pattern reversal stimulation. As a result of the cortical dipole imaging, two separated areas with relatively large amplitude were found at the occipital lobe. These areas were not confirmed by the scalp potential map. Furthermore, we confirmed a phase difference between two signal areas. These signals moved from the occipital lobe toward the temporal lobes. It was considered that our result demonstrated the visual signal information propagated along the ventral stream.
