Visual area V1 responses were next examined for changes in alpha-gamma PAC. Specifically, we set out to test whether the coupling between alpha-band phase and gamma-band amplitude was altered during presentation of the visual grating. Phase-amplitude comodulograms were produced between a range of phase frequencies (7–13 Hz) and amplitude frequencies (34–100 Hz), using the four algorithms described in Section Methods: MVL-MI-Canolty; MVL-MI-Özkurt; PLV-MI-Cohen, and KL-MI-Tort. Grating and baseline comodulograms were compared using cluster-based non-parametric statistics (Maris and Oostenveld, 2007).
