Sensory deprivation into maturity further diminishes the cone-mediated b-wave. Cone-dominated ERGs from normal-reared and dark-reared adult retinas under identical stimulus conditions from Fig. 7. (A and B) Dark rearing into adulthood nearly eliminates transmission from cones to their bipolar cells across all light intensities. (B) Population-averaged cone-driven b-wave amplitudes plotted against flash intensity from normal-reared (nr, closed circles; n = 7) and dark-reared (dr, open circles; n = 14) retinas. (C) Dark rearing does not alter the b-wave:a-wave ratio. Response ratios represent averages from normal-reared (nr, closed circles; n = 10 retinas) and dark-reared (dr, open circles; n = 10 retinas) animals plotted as a function of light intensity. (D) Dark rearing alters cone-driven a-waves. Blockers were perfused and the same stimulus families used in A elicited a-waves (red traces). Insets utilize the same method as Fig. 7 C to obtain amplification constants (A; s⁻²). The dashed horizontal indicates response saturation (R_max). (E) Cone-driven a-wave amplitudes are reduced at most light intensities while their sensitivity remains normal. Intensity–response relationships were best-fit with Eq. 2 and appear as follows: nr (solid green), dr (dashed green). Half-saturating intensities (I_1/2) = vertical lines. (F) Dark rearing reduces the sensitivity of synaptic transmission. Representative synaptic transfer functions from a single normal-reared (closed circles) and dark-reared (open circles) retina. The synaptic transfer function was fit with Eq. 6 and appear as follows: nr (solid green), dr (dashed green). Vertical lines = half-saturating a-wave values (solid lines: k_nr = 11.4 µV; dashed lines: k_dr = 33.1 µV). Average half-saturating a-waves from all retinas (k_nr = 15.7 µV, k_dr = 33.3 µV; P = 0.02). Error bars represent mean ± SEM. Single, double, and triple asterisks indicate P values of <0.05, <0.01, and <0.001, respectively.