EEG power in the 1–20 Hz range for NREMS, REM sleep (REMS) and wake during baseline. (A) EEG spectral power in cry1,2-/- (thick lines) and wild type mice (thin lines). Differences between the genotypes are limited to NREMS delta power. (B) Delta power (1–4 Hz) during wake-to-NREMS transitions in the baseline light (left) and dark (right panel) period. Gray horizontal bars underneath the curves indicate significant genotype differences (P < 0.05; post-hoc t-tests). Error bars span ± 1 SEM.