Figure 3.

High-speed walking bouts reveal specific phase relations between neural activity and the stride cycle

(A) Schematic of experimental configuration and definitions.

(B) Example traces of Vm (black: raw, green: filtered), Vf, Va, and the left front leg phase, triggered at the stance onset.

(C) Left, distribution of the magnitude of the oscillations during walking (magenta) versus quiescence (gray) across 19 fly-cell pairs. Right, mean amplitude of oscillations during walking (3.95 ± 0.29 mV) and quiescence (1.79 ± 0.22 mV) (p = 0.00013, Z = 3.823, the signed-rank test).

(D) Left, schematic of the experimental configuration. Right, tuning of right HS cells (Vm_|5 Hz) to the stride cycle of the left front leg during spontaneous walking in darkness (black) and under visual feedback (green, n = 8 fly cell pairs, grand mean ± SEM).

(E) Probability distributions of the phase of the stride cycle at the peak of Vm_|5 Hz oscillation (contralateral/ipsilateral cells, 4,182–4,747/1,937–2,269 strides, n = 19/11 fly cell pairs). Black lines indicate the mean per cell.

(F) Vm_|5 Hz as a function of the stride cycle of the left front leg during opto-runs (right cells: solid orange, n = 19 fly cell pairs; left cells: dashed maroon, n = 11 fly cell pairs).

See also Figures S2–S4 and Video S1.