Finally, the KL-MI-Tort approach estimates PAC by quantifying the amount of deviation in amplitude-phase distributions. This involves breaking fp into 18 bins, and calculating the mean amplitude within each phase bin, normalized by the average value across all bins. Although the number of phase bins chosen is arbitrary, the specific number (9, 18, or 36) does not seem to influence PAC estimation (Figure S1; van Driel et al., 2015). The modulation index is calculated by comparing the amplitude-phase distribution (P) against the null hypothesis of a uniformly amplitude-phase distribution (Q).
