Figure 3. Circadian rhythms in the wild-type and Gnat1^−/− cone ERG. Wild-type mice showed significant difference in b-wave amplitude (A) and implicit time (B) over the course of light adaptation when measured at CT6 (open circles) compared to CT18 (closed circles) F test curve fit comparison p<0.0001 for each parameter. Similar effects of circadian phase were observed on b-wave amplitude (C; F test p<0.0001) and implicit time (D; F test p<0.0001) in Gnat1^−/− mice. All data are shown as mean±SEM. Replicates for A and B were: n=10 (CT6), n=8 (CT18), for C and D: n=8 (CT6), n=6 (CT18). The estimated parameters for curve fit for the curves in A were, CT6: Y₀=-5.061 a=149, k=0.124, CT18: Y₀=-2.029 a=127, k=0.1082. Estimated parameters for B, CT6: Y₀=83.39, a=54.94, k=0.143, CT18: Y₀=96.08, a=59.07, k=0.176. Estimated parameters for C, CT6: Y₀=88.72, a=194.4, k=0.127, CT18: Y₀=46.62, a=159.3, k=0.0666. Estimated parameters for D, CT6: Y₀=56.23, a=51.78, k=0.283, CT18: Y₀=59.20, a=52.11, k=0.087.