Fig. 2: Consistent firing sequences during assembly activation predicts successful memory and may result from member neurons locking to different phases of the underlying gamma oscillation.

A Schematics of three example assemblies with member neurons colored according to the expected firing order within activation events. B Cumulative distribution functions of spike times within activation events for each assembly member neuron, colored according to the key displayed in (A). C Spike rasters of assembly member neurons within five example activation events demonstrating the expected firing sequence. D Comparison of MI for each of the three assemblies from (A) to a null distribution obtained by shuffling spike times within activation events (n = 1000 shuffles, p = 0.0009). E Distribution of z-scores obtained by comparing the actual MI to the null distribution for each assembly (one-sample t-test, t(n = 45) = 7.454, p = 1.24e-6). F Comparison of the average MI across assemblies to that of each shuffle (permutation test, n = 1000 shuffles, p = 0.0009). G Positive Spearman correlation between MI and overall recall fraction (spearman rank correlation, n = 45, r = 0.305, p = 0.0419). H Comparison of the observed MI-recall fraction correlation to a null distribution obtained by shuffling spike times before re-calculating (permutation test, n = 1000 shuffles, p = 0.0020). *p < 0.05. **p < 0.01. ***p < 0.001. Source data are provided as a source data file.