Fig. 2: Preplay of memory-relevant spiking sequences.
From: Backbone spiking sequence as a basis for preplay, replay, and default states in human cortex
a Four individual spiking sequences from different cognitive periods in a testing session that are all significantly similar to one another. Each sequence shown is separated from the previous sequence by ~10 min in order to span the entire recording session. b Comparison of resting backbone sequence (2 min before task began) to spiking sequences during subsequent memory encoding epochs (one-sided t-test against 0 as null, incorrect: t(5) = 2.95, p = 0.0159; correct: t(5) = 2.54, p = 0.0259). (*) indicates p < 0.05 and n.s. indicates not significant. Error bars indicate SEM across participants. c Representative example of an MTL ripple co-occurring with a significant preplay sequence during the rest period. d Average similarity between resting cortical sequences and encoding sequences triggered to the onset of MTL ripples. Significant difference in similarity between correct versus incorrect trials is indicated by the bar (cluster-based permutation procedure correcting for multiple comparisons, p <0.001), indicating that MTL ripples precede cortical preplay by ~150 ms. Error bars indicate SEM across participants. e Sequence similarity between cortical spiking sequences during rest stratified based on if they were coupled to an MTL ripple (left) or not (right). Only MTL coupled preplay events demonstrate a significant difference in similarity between subsequently correctly and incorrectly encoded memories (N-way ANOVA with post hoc Tukey’s test, p = 0.034). Error bars indicate SEM across participants. N = 6 participants for all statistical tests in this figure.
