Fig. 3: The network gain maintains a trace of the visual cue in darkness.
From: Population dynamics of head-direction neurons during drift and reorientation
a, Offset traces (light blue) across darkness events D1 (n = 42), D2 (n = 35), D3 (n = 33) and D4 (n = 35). The black lines show the mean drifts. For D2, D3 and D4, only darkness epochs that follow a correct reset were considered. b, Drift variability increases with time during dark epochs compared with the baseline (baseline: n = 42 events; darkness: n = 145 events; two-sided Wilcoxon rank-sum test, P = 7.5211 × 10−23, Z = 9.84). c, The triggered average of network gain shows an abrupt drop at the transition between cue-on and cue-off epochs, marked by the dotted red line (two-sided Wilcoxon rank-sum test, P = 9.0165 × 10−12, Z = 6.81; comparison between mean values over 40 s before and 40 s after cue removal; the same data as in a). d, Network gain tuning curves at the baseline (light blue) and during darkness (dark blue). The internal HD is relative to the baseline cue location (dashed yellow line). The gain remains flat at the baseline; however, it peaks around the internal cue location ([−90:90]°) and drops sharply away from it ([−180:−90]U[90:180]°) in darkness (n = 145 events; two-sided Wilcoxon rank-sum test, P = 5.8683 × 10−7, Z = 5.00). e, Network gain heat map. Note the increase in amplitude and width of the gain tuning curve at a larger head angular velocity. All clockwise sessions were reflected across the x axis and transformed into counter-clockwise ones. Signals in c and d are shown as mean (solid line) ± s.e.m. (shaded area). Bar graphs in b–d show the mean ± s.e.m. with individual datapoints.
