Fig. 3.

Quantification of dark-adapted ERG responses to flashes of light recorded in the middle of the day (ZT6) and in the middle of the night (ZT18). Mice (3–4 months old) were dark-adapted for at least 30 min before the recordings were performed. Data are presented as mean ± SEM; n = 4–6 for each time point and genotype. Two-way ANOVA indicated a statistically significant contribution of the time of day for the a-wave (P < 0.05) and b-wave (P < 0.001) amplitudes and for genotype (P < 0.005, a-wave; P < 0.001, b-wave). The implicit time of the a-wave and b-wave was also affected by the time of the day (P < 0.001 in both cases), but not by the genotype (P > 0.1 and P > 0.1, respectively).