A new method based on Correlation Coefficients to map coherent brain sources

Fully correlated neural activity across different brain regions is suggested to be a possible mechanism for functional integration. Noninvasive analysis of the coherent sources among cortical areas is possible by mapping coherent sources on the scalp. We developed a method using scalp EEG recordings to map the coherent sources. Firstly the correlation coefficient matrix was estimated. By statistics tests, significant correlations between EEG channels were picked out. The sum of CCs between one channel and all the other channels is taken as the mapping index. Theoretical analysis shows this method can map coherent sources. Both computer simulation and real visual evoked potentials (VEP) test confirm that, compared to traditional power mapping, the presented method is sensitive to the combination of the correlated brain sources with different energy levels.