Note that the measure R is completely independent of the amplitudes of the time series as well as any constant phase lag between them. Furthermore this measure has been shown to reliably reflect relative changes in synchrony even in the strong presence of noise (Mormann et al., 2000). Since the variance over time was very low for the obtained synchrony profiles (<0.01 on average for different contact combinations, frequency bands, and patients, cf. Bullock et al., 1995b), matrices were subsequently averaged over time, resulting in a single synchronization matrix per patient and EEG band (cf. Figure 2).
