Fig. 6.
Assessing the phase-locking between the amplitude envelope AfA and fp. A, top panels: shown are a synthetic local field potential (LFP) example, along with the signal filtered at theta and gamma ranges bottom traces. The amplitude envelope (AfA) of the gamma filtered signal is also shown (thick line). Bottom panels: phase time series of theta (top) and gamma amplitude (bottom). B: same as before but for a case with stronger phase-amplitude coupling (as judged by the amplitude envelope). Notice that the phase-time series of the amplitude envelope is identical to the previous case and thus the levels of phase-locking to the fp rhythm are the same. Therefore CFC measures dependent on the level of phase-locking between AfA and fp are, in principle, potentially not able to track CFC intensity (for better clarity of the proof of principle, no noise was added to the synthetic signals shown in this figure).