To construct the functional network, the first step is to obtain the connectivity matrices representing inter-relations between brain regions. In order to obtain connectivity matrices, different methods were proposed [50]. In this study, we used Pearson’s correlation, which has been frequently used in functional network construction. The correlation coefficient between two electrodes, x and y, can be calculated as [32]:(1)rx,y=cov(x,y)var(x)var(y) where cov(x, y) is the covariance between node x and node y, and var(x) and var(y) are the variances of node x and node y, respectively.
