Fig. 3. The relative timing between global and local motion signals in SAC dendrites is different for inward and outward motion directions.

a ASAP3-Vm relationship from an ASAP3-expressiong SAC by simultaneous imaging and voltage clamp recording at the soma. b Summary of ASAP3 -Vm relationship measured at the soma. Left: ASAP3 traces (Mean: solid lines; SD: dashed lines, 9 cells). Right: ASAP3-Vm plot. ASAP3 signals are averaged during each voltage step. Error bars represents SEM. c Upper: Dendritic imaging of ASAP3 during the moving bar stimulus. ROIs (colored squares) were placed along the dendrite. Numbers indicate distances (µm) from the soma. Lower: Overlay of the average somatic ASAP waveform (red) and 20 individual trials of somatic Vm traces of a SAC (gray). ASAP3 signal is converted to voltage based on the ASAP3-Vm curve. Scale bar: 10 µm. d Motion-evoked ASAP3 signals are grouped into 20 µm bins centered at different radial distances. Upper: schematics of outward (red arrow) and inward (black arrow) moving bar relative to the binned imaging areas (colored rectangles). Middle: Mean (solid lines) and standard deviation (SD) (dashed lines) of ASAP3 signals in outward (red) and inward (black) motion directions. Gray solid horizontal lines represent the baseline ASAP3 signal measured between moving bar trials. Vertical colored lines indicate the time when the leading edge of the bar arrives at the imaged ROI in the upper schematic. From soma to distal bins: n = 5, 7, 3, 5, 2 cells. Lower: Somatic signals are aligned according to the time when the bar arriving at each dendritic ROI (colored vertical lines). e Summary of the relative timing between the arrival time of local synaptic inputs and the peak of ASAP3 signal for each ROI location. Negative values indicate the local synaptic inputs before the peak time of the ASAP3 signal. From soma to distal bins: n = 5, 7, 3, 5, 2 cells. Box plots are defined as in Fig. 2a. Source data are provided as a Source Data file.