Fig. 1.

pDSGC Off responses are contextually modulated. a Schematic shows side view of the laminar organization of bipolar cells (BCs), SACs and On-Off DSGCs in the inner plexiform layer (IPL). b Simplified schematic shows major types of synaptic inputs onto On-Off DSGCs. c Left: Schematics show the visual stimulus conditions. A schematic of a pDSGC is shown in the center of each stimulus to indicate the relative sizes of DSGC dendritic arbors and visual stimuli. The red arrows indicate the moving directions of the drifting gratings, and the black arrow at the top indicates the preferred direction of the pDSGC. Right: Example Off spike traces of a pDSGC from a control mouse evoked by the stimuli on the left. Spike traces are overlays of 10 grating cycles (also see Methods) for this and subsequent figures. d Scatter plots compare Off firing rate during uniform versus compound gratings. Direction-contrast vs uniform grating: n = 29 cells from 13 mice; phase-contrast vs uniform grating: n = 22 cells from 9 mice. Wilcoxon signed-rank test, ***p < 0.001. Grey dots represent individual cells, red dots with error bars indicate the median ± IQR, and diagonal red dashed lines are unity lines. The data point corresponding to the example traces was labelled by the black arrow. e Direction selectivity index (DSI) of pDSGC Off spiking in different stimulus contexts. Friedman test: n = 10 cells from 4 mice, *p = 0.025. Wilcoxon signed-rank test with Bonferroni correction: center only vs uniform grating: *p = 0.0039; center only vs direction-contrast: p = 0.23; center only vs phase-contrast: p = 0.70. Box plots represent minimum/first quartile/median/third quartile/maximum values, open grey dots represent individual cells, grey crosses are outliers defined by Tukey’s fences. f pDSGC Off firing rate when center gratings drift in the null direction. Friedman test: n = 10 cells from 4 mice, p = 0.29. See also Supplementary Fig. 1 for further identification of Off firing rate during different stimulus contexts, and Supplementary Movie 1 for visual stimuli