Fig. 4: PAC neuron selection and local activity.

a, The binning used for PAC neuron selection for an example hippocampal neuron. Theta phase, binned into ten groups, and gamma amplitude (amp.), median split into low and high, were used to predict the spike counts of each neuron from the MTL during the delay. The spike count was higher during high-gamma amplitudes (gamma main effect) and differed in their theta phase distribution between high and low gamma amplitudes (interaction effect), resulting in selecting this neuron as a PAC neuron. b, The proportions of neurons qualifying as PAC neurons. Cat., category. c,d, FRs of PAC neurons were positively correlated with single-trial estimates of TG-PAC in the hippocampus (c; n = 79, P = 0.028, mixed-effects GLM), but not in the amygdala (d; n = 163, P = 0.98; GLM results are shown in Supplementary Table 4). e,f, FRs of PAC neurons during the maintenance period differed between correct and incorrect trials in the hippocampus (e; n = 63; correct versus baseline, P = 0.01; incorrect, P = 0.33; correct − incorrect, P = 0.0001; 16 neurons were excluded due to insufficient data in the incorrect condition), but not in the amygdala (f; n = 156; correct, P = 0.0001; incorrect, P = 0.0001; correct − incorrect, P = 0.45; 7 were neurons excluded due to insufficient data in the incorrect condition). FRs are shown as the percentage change compared with the baseline (−0.9 to −0.3 s). g,h, FRs did not differ between loads (hippocampus (g): n = 79; load 1, P = 0.03; load 3, P = 0.01; load 3 − load 1, P = 0.20; amygdala (h): n = 163; load 1, P = 0.0001; load 3, P = 0.0001; load 3 − load 1, P = 0.80). For g–j, statistical analysis was performed using two-sided permutation-based t-tests. For e–j, data are mean ± s.e.m.