Chronobiology & health: Why your nervous system thrives on biological rhythms.

Look closely at human biology, and you will find that almost every physiological process is rhythmic. Our cells, organs, and nervous systems do not operate at a constant, linear output. They rely on complex biological clocks, from the millisecond firing of heart rate variability (HRV) and the 24-hour circadian rhythm to monthly infradian hormonal cycles.