For each subject, we calculated pairwise zMVL values among ICA component pairs within each region as introduced previously (10). That is, the β phases and γ amplitudes were not only extracted from the same component, but also from different components. The method for computing n ICA components in a region was introduced in “Region-based source analysis.” In brief, we calculated the epochs of the time series of zMVL values among n × n component pairs in a region. We then computed a single time series by computing the weighted average of zMVL values across trials and n × n component. The weights for averaging were defined as the percentage of variance accounted for by each component pair in the region.
