Figure 2.

Single-neuron coactivation drives ensemble transitions. A, Change points (CPs), represented by red dots, and state transitions (vertical dashed green lines) are superimposed to a raster plot of simultaneously recorded neurons (same trials as the first three in Fig. 1A). x-axis for top, time preceding taste delivery (0 = stimulus delivery); y-axis, ensemble neuron index. B, CPTA of ensemble transitions for the empirical dataset (black) and for the trial-shuffled dataset (blue). Shaded bounds represent SE. Thick black line below traces indicates p < 0.05 (bin-wise t test with multiple-bin Bonferroni correction). x-axis, time lag from CP (seconds); y-axis, probability of a transition given a CP at t = 0. C, Fraction of transitions co-occurring with CPs within a 200 ms window before the state transition (significant window from B). x-axis, number of single neuron's CPs divided by the ensemble size; y-axis, fraction of transitions co-occurring with CPs (%). D, Correlation (φ² statistics) between the signs of single neurons' and ensemble firing rate changes for the empirical (“Data”) and simulated datasets. In the latter, 90%, 50%, and 0% of simulated neurons had firing rate changes matched to those of the whole ensemble (boxes in box-plots represent 95% CIs). y-axis, φ² statistics. E, Firing rate distributions across states for representative neurons 2 and 3 from the ensemble in Figures 1A and 2A (color-coded as in Fig. 1A; each curve represents the empirical distribution of firing rates in each state). x-axis, firing rate (spikes/s); y-axis, probability density of states. F, Number of different firing rates per neuron across all sessions: 42% of all neurons had ≥3 different firing rates across states. x-axis, minimal number of different firing rates across states; y-axis, fraction of neurons (%).