Sleep is one of the best-studied circadian behaviors, and what many of us think of when we think of circadian rhythms.

The 2-process model of sleep explains how homeostatic drive and the circadian clock control the timing of sleep.

Two experimental techniques that sleep researchers use to separate processes C and S are called “napping protocol” and “forced desynchrony”:

To learn more about sleep in humans, we recommend the following interviews with prominent sleep biologists: