Next, the coupling between fp and fa was quantified using four common PAC approaches1: the Mean-Vector Length modulation index, originally described in Canolty et al. (2006); the Mean-Vector Length modulation index described in Özkurt and Schnitzler (2011); the phase-locking value modulation index described in Cohen (2008); and the Kullback-Lieber modulation index described in Tort et al. (2010b). These approaches were selected due to their popularity in the MEG/EEG PAC literature (e.g., Mathewson et al., 2011; Khan et al., 2013; Bonnefond and Jensen, 2015; Cho et al., 2015), and to demonstrate the diversity of PAC results based on the algorithm selected.
