Extended Data Fig. 4: Spike properties of fan cells in Sim1-Cre mice.

(a)–(c), spike properties of fan cells. Fan cells were recorded in a session with Odour A and Odour B (AB session). After ~20 trials in AB session, associative learning (AB12) session was tested (T1-T5). T5 in error sessions is also shown. (a) Spike firing of 213 fan cells. Mean spike activity was averaged in 50 ms bins and shown in z-score compared with −1 – 0 s before odour onset. In this panel, cells were sorted using a cluster analysis of firing property in T5. (b). Mean firing rate of 213 fan cells shown in z-score. (c) Percent responsive cells in periods of 0.5-1.5 s (odour), 2-3 s (delay) and 3-4 s (choice) after odour onset. Neurons with significant firing during each period were counted (Wilcoxon signed-rank test, p < 0.05). (d) Percent responsive cells in correct T5 (top) and error T5 (bottom). Neurons with significant firing during 0.5-1.5 s after odour onset were counted (Wilcoxon signed-rank test, p < 0.05). Asterisk denotes lower percentage of A-1 responsive cells in error T5 than that in correct T5 (p < 0.05, chi-square test; p < 0.05 for A-1 cells, post-hoc residual test with false discovery rate correction for multiple comparisons). (e)Trajectories of neural firing of fan cell population (top), Euclidian distance between odour trial types (middle) and mean Euclidian distance and similarity index during 0.5-1.5 s after odour onset (cue period) for timepoints T1 – T5 of correct sessions (bottom). Ninety-fifth percentile distance obtained from shuffled data denotes significant distance (red line). Data during 2-3 s (delay) and 3-4 s (choice) after odour onset were also plotted. (f). Same as (e), but for error sessions where mice did not learn new associations. (g). Example trajectories obtained from shuffling analysis. Trajectories of neuronal data obtained from three shuffled data in correct T5 sessions are shown. (h). Distribution of mean Euclidian distance obtained from shuffle data in correct T5. Distance obtained from six possible odour pairs were averaged and plotted. A 95^th percentile of the distribution (red) was used for the cut-off indicating significant distance.