Extended Data Figure 7. Selectivity for direction varies among DSGC subtypes.

a, Polar plots of local DS preference among ON-DSGCs, plotted on standard flat retinas (above) and in reconstructed hemispherical form (below). Increasing the stringency of the criterion for direction-selectivity index (DSI) from 0.3 to 0.5 reduced the number of N-cells (top left) by 95%, but other subtypes by only 42-60% (sample zone: red rectangle). Thus, N-type ON-DS cells are unusually poorly tuned, and may have been excluded on that basis in previous studies reporting only three ON-DSGC subtypes. b, Left panels of (a) reproduced with color coded subtypes. Each cell’s subtype assignment determined by which of the four cardinal translatory flow fields was most closely aligned with its preferred direction. N, blue; T, green; D, orange; V, magenta. c, Line histograms showing the distribution of DSIs among each ON-DSGC subtype. The distribution for N-type ON-DSGCs is shifted to lower DSI values. d, Median DSI and first and third quartiles for each ON-DSGC subtype. N-cells were significantly less well tuned. e-h, same analysis as a–d, but for ON‐OFF DSGCs. There were significant differences among subtypes but the stringency of the DSI criterion did not affect the relative abundance of subtypes. i,j, Mean calcium responses (n=497) to preferred direction of bar motion of individual subtypes of ON‐DSGCs (i) and ON-OFF-DSGC (j). k,l, Histograms (k) and mean values (plus 1^st and 3^rd quartiles) (l) of latency to ON peak for each DSGC subtype, measured from estimated time of arrival bar edge at receptive field (see Methods). Latency differed significantly between each ON-DSGC subtype and its matching (homonymous) ON-OFF-DSGC subtype. m,n Histograms (n) and median plus 1^st and 3^rd quartiles (n) of the slope following the ON peak for each subtype of ON- and ON-OFF-DSGCs (see Methods). See Supplementary Note 12 for statistics and further details.