“…They calculate the time dependency (Granger causality) (Granger, 1969) or state dependency (convergent cross‐mapping) (Sugihara et al., 2012) between the variables. These methods were relatively difficult to implement in mutual causation systems (Yang et al., 2018). In contrast, causal decomposition uses the ensemble empirical mode decomposition (Huang et al., 1998; Wu & Huang, 2009; Wu, Huang, Long, & Peng, 2007) to decompose the LFP pairs (in our case, LFPs from CA1 and MEC) into a finite number of intrinsic mode functions, and then calculates the phase coherence values between the intrinsic mode functions.…”