Figure 1. Endogenous circadian rhythm in hunger.
Cosinor model is shown as mean (black line) ± 95% confidence interval (gray area). In addition, averaged data are shown grouped into six 60°(~4 h) bins (open circles). The model and data points are ‘double-plotted’ to better portray circadian rhythmicity. Bottom X-axis, circadian phase; top X-axis, corresponding clocktime; horizontal gray boxes, average habitual scheduled sleep episode; P-value, statistical significance of a circadian rhythm in hunger.