Light responses of ON-OFF ganglion cells are slower in NCBE-deficient mice.

<p><b>A–C,</b> Single PSTH of representative NCBE KO (red) and WT (black) ON-OFF ganglion cell light responses, evoked with increasing spot sizes (<b><i>A</i></b>), light intensities (<b><i>B</i></b>) and stimulus frequencies (<b><i>C</i></b>). <b><i>D, G,</i></b> No significant differences were found between the ON <i>(A1τ2)</i> and OFF(<i>A2τ2)</i> response durations of WT and KO cells when spot size was increased [<b><i>D</i></b>; top (ON): F(1, 29) = 0.06; p = 0.8141; bottom (OFF): F(1, 29) = 0.01; p = 0.9425]. However, when light intensity was increased, response durations were longer in NCBE KO mice [<b><i>G</i></b>; top (ON): F(1, 29) = 5.98; p = 0.0207; bottom (OFF): F(1, 29) = 4.50; p = 0.0426]. <b><i>E, H</i></b><b>,</b> Time to peak of the ON response <i>(L1</i>) but not of the OFF response (<i>L2</i>) was significantly increased in NCBE KO when either the spot size [<b><i>E</i></b>; Top (ON): F(1, 29) = 6.13; p = 0.0194; bottom (OFF): F(1, 29) = 1.94; p = 0.1741] or the intensity were increased [<b><i>H</i></b>; top (ON): F(1, 29) = 12.56; p = 0.0014; bottom (OFF): F(1, 29) = 0.53; p = 0.4736]. <b><i>F,</i></b> No significant differences were found between the normalized ON (<i>A1</i>) and OFF response amplitudes (<i>A2</i>) with increasing spot size (<b><i>F</i></b>; top (ON): F(1, 29) = 0.03; p = 0.8565; bottom (OFF): F(1, 29) = 0.28; p = 0.5978). <b><i>I,</i></b> Normalized cell responses <i>(A1)</i> of a flicker series. NCBE KO cells showed decreased responses and were not able to follow higher frequencies comparably to NCBE WT cells (<b><i>I</i></b>; F(1, 29) = 2.94; p = 0.0969). Vertical lines an <b><i>A</i></b> and <b><i>B</i></b> represent stimulus onset and offset, respectively. Values are presented as mean ± SEM. Statistical values were obtained from repeated measurement ANOVA. NCBE WT (n = 16), NCBE KO (n = 15).