Fig. 1: CBASS links state-dependent changes in gamma (30–80 Hz) activity to defined network events.

a, Schematic of laminar V1 recordings in head-fixed mice on a running wheel. b, Example data showing one LFP channel and its short-time Fourier transform during a transition from quiescence to locomotion (purple). a.u., arbitrary units. c, Average LFP power across channels (n = 19 mice), showing a selective power increase in the gamma range (30–80 Hz) during locomotion. d, CBASS applied to data from V1 during locomotion. The multichannel LFP (black) is filtered in the gamma (30–80 Hz) range. Candidate events are selected at the troughs of the filtered signal in a reference channel, and events (orange bars) whose phase and amplitude profile across channels predicts locomotion are retained. e, Average LFP around gamma events (left) and the associated CSD profile (right). Events are associated with a propagation of activity from layer 4 to superficial layers, followed by deep layers. Orange dashed line denotes gamma event. f, Rate of CBASS-detected gamma events around locomotion onset (L-on; n = 19 mice). g, Event rate increases during locomotion (L; n = 19 mice). Q, quiescence. h, Average distribution of inter-event intervals for gamma events. Events are divided into three groups: (1) burst, events whose closest neighbour is within 27.3 ms (1.5 average cycle); (2) distributed, events whose closest neighbour is further than 27.3 ms but within 90.9 ms (5 average cycles); and (3) isolated, events whose closest neighbour is further than 90.9 ms (n = 19 mice). The expanded view of the ‘isolated’ potion of the plot is also shown (inset). Black dashed lines denote divisions between groups. i, Population average distribution of firing around burst, distributed and isolated gamma events for extracellularly recorded regular-spiking (RS; black; n = 457 units) and fast-spiking (FS; red; n = 260 units) units across layers. Orange dashed line denotes gamma event. j, Average CSD profile of burst, distributed and isolated gamma events (n = 19 mice). Orange dashed line denotes gamma event. The error bars denote the s.e.m; and the shaded areas indicate mean ± s.e.m. For statistical significance, *P ≤ 0.05 and ***P ≤ 0.001. See Supplementary Table 1 for detailed statistics and Supplementary Table 2 for statistical samples.