Fig. 6

(a) Representative flash response family from zebrafish rods and cones obtained by ex vivo ERG recordings. The ERG a-wave was inverted to positive direction for consistency with the single-cell recordings. Flash wavelength and intensity: 500 nm, 1–32,000 photons μm⁻². Red trace was obtained at 100 photons μm⁻². (b) Intensity-response relationships of the overall response (●) and its estimated rod (■) and cone (▲) components. Rod and cone plots were fitted with Naka-Rushton function with R_max = 25 µV, I_1/2 = 13 photons µm⁻², and n = 1.9 for rod data, and with R_max = 72 µV, I_1/2 = 425 photons µm⁻², and n = 1.0 for cones. Plots are mean ± SEM (n = 7). (c) Responses obtained with 405 nm (violet), 500 nm (green), and 575 nm (orange) flash at 32,000 photons μm⁻². (d) Estimated intensity-response relationships of the four cone subtypes when stimulated with 405 nm flashes, based on their spectral sensitivity (Fig. 2) and intensity-response relationships obtained with near λ_max flashes (Fig. 4). A grey line indicates 32,000 photons µm⁻².