the subject’s preoperative MRI image that was normalised to a canonical template MRI scan. Raw time series were band-pass filtered between 5 and 35 Hz prior to computation of the covariance matrix. As explained in (Litvak et al., 2011a) we used the imaginary part of the cross-spectral density to obtain a single time series for a resultant dipole orientation per source. We computed the full PAC spectrum between beta and HFO frequencies for each pair of STN channel and corresponding cortical location using the same settings for PAC within the STN, as described above.
