Fig. 3: The relative EEG power of NREM sleep increases at ZT4 on the first day of SD and at ZT3 and ZT4 on the seventh day of SD.

The relative EEG power was calculated for wakefulness, NREM sleep, and REM sleep from the mice (n = 6–7) during the 24 h recordings. Power density plot for A NREM sleep, B REM sleep, and C wakefulness during 24 h on all days. D Relative delta EEG power for NREM sleep per hour for all days. The shaded gray indicates the dark phase (ZT12-0) and the colored shading indicates the timing of SD (ZT2-6). Not all animals entered NREM sleep every hour; thus, the line-types indicate the mean across animals and the colored shading around the line indicates SEM. A repeated measures and paired mixed-effect model with the Geisser-Greenhouse correction with a Tukey’s multiple comparisons test was performed to compare relative EEG power per hour for NREM sleep. Baseline vs 1st day of SD - *p < 0.05 and baseline vs 7th day of SD ¤p < 0.05.