Supplementary Figure 10: Visuomotor interactions in HS cells

(a) Top: Velocity-tuning maps under replay visual stimulation per cell. Bottom, visual and angular velocity maps per cell. (b) Walking velocity tuning map across the population of right-side HS cells under replay trials (N=13). (c) Estimate of the visual modulation of HS cells’ activity under replay conditions in quiescent segments: the visual stimulus is scaled by the velocity tuning curve of HS cells (see Methods) to obtain an effective visual stimulus (red trace). This effective stimulus is convolved with a response kernel (see Methods) to estimate the visual-induced activity in HS cells (blue trace). For comparison, the observed visual responses under identical conditions is shown (black trace). The delay of the kernel was obtained by cross-correlation analysis between HS cell responses and visual stimuli in quiescent segments. (d) Distribution of θ (Fig. 6) for each cell for fits with R²>0.7 (top, 9/13 cells, mean±SD=37±9°). Black: mean value; red, θ for the population map shown in Figure 6b. (e) Predictions from ideal random forest decoders (see Methods) of the sum of the visual velocity (Vv) and the fly‘s angular velocity (Va, red traces), or the difference between the two (blue traces). The input signals for the decoder were either the estimated Vm dynamics from the visual stimulus and the three-component walking of the fly (top row), or the estimated Vm dynamics from Vv and the fly’s Va (bottom). c=correlation coefficient between the predicted and the observed values of the sum or difference between Vv and Va. (f) Cross-correlation coefficients between the predicted and the observed velocities for each recorded cell, for the two different inputs to the ideal decoders. Bars: the mean values across cells. Color code as in (e).