Extended Data Fig. 10: hΔB bump deviations.

a. hΔB ΔF/F in each FB column as a fly walks in closed loop with a visual cue. When the fly steps laterally (indicated by the arrowhead), the bump deviates from the cue. b. Histograms showing the difference between cue position and bump position, mean-centered in each experiment, and binned by translation direction; n=4 flies for hΔB, 16 flies for PFNd, and 11 flies for PFNv, # = relatively poor correlation between cue and bump; these experiments are omitted from panel c. At more lateral translation angles, the hΔB bump deviates away from where it would be when the fly is walking forward. c. Mean difference between cue position and bump position. Each set of connected symbols is one experiment. For hΔB neurons (n=4 flies), we found the shift was significant when comparing left translation-heading deviations to centered translation-heading deviations (P=0.0013, 2-sided paired-sample t-test with Bonferroni-corrected α = 0.0167, CI = [−0.460, −0.191] radians) and when comparing right translation-heading deviations to centered translation-heading deviations (P=0.0115, α = 0.0167, CI = [−0.698, −0.0473] radians). For PFNd neurons (n=16 flies), the shift is not significant when comparing left translation-heading deviations to centered translation-heading deviations (P=0.0215, 2-sided paired-sample t-test with Bonferroni-corrected α = 0.0167, CI = [−0.180, 0.0044] radians) or when comparing right translation-heading deviations to centered translation-heading deviations (P=0.4790, α = 0.0167, CI = [−0.0467, 0.0812] radians). For PFNv neurons (n=9 flies; 2 flies were excluded from our analysis), this shift is significant when comparing left translation-heading deviations to centered translation-heading deviations (P=0.0011, 2-sided paired-sample t-test with Bonferroni-corrected α = 0.0167, CI = [0.0544, 0.222] radians) but not significant when comparing right translation-heading deviations to centered translation-heading deviations (P=0.0313, α = 0.0167, CI = [−0.0135, 0.1848] radians); note that the shift is opposite to hΔB neurons. d. Same as Fig. 4f-g but color-coded by fly (n=28 epochs in 10 flies for hΔB, n=22 epochs in 6 flies for EPG). e. Maximum bump deviation versus φ, measured in all epochs ≥300ms when the φ was consistent over the epoch. Within each fly, epochs are binned by φ and then averaged (○) before averaging across flies (●). For hΔB neurons, the data are close to the identity line (purple); while for EPG neurons, the data are close to the zero line (gold). n=10 flies for hΔB, n=10 flies for EPG. f. Normalized hΔB bump amplitude versus φ, binned by speed (n=11 flies).