Circadian rhythms control the physical, mental, and behavioral changes an organism experiences over a 24-hour cycle. Almost all living things, from bacteria to humans, have circadian rhythms. They’re controlled by a biological clock, which is composed of proteins encoded by thousands of genes that switch on and off in a specific order in response to the daily cycle of day and night.
Circadian rhythms can influence important body functions like hormone levels and temperature. The most noticeable effects of circadian rhythms are predictable sleep patterns. Traveling across several time zones or working the night shift can disrupt these sleep patterns and cause drowsiness, poor coordination, and difficulty staying focused.
In 2017, three NIGMS-supported researchers won the Nobel Prize for finding a gene in fruit flies that helps control circadian rhythms. Similar genes in the human body affect sleep patterns, sharpness of brain functions, and more.
Issue of Pathways student magazine focused on circadian rhythms (grades 6-12).
An interactive that explores different regions of the brain when someone is conscious, asleep, or unconscious.
