Circadian Health Glossary

Biological Rhythms

Every living organism on Earth follows a natural, cyclical pattern in various biological processes. These cycles can range from the millisecond-level flickers of muscle contraction to the yearly rhythm of hibernation in certain mammals. In humans, the most well-known and studied rhythmic pattern is the circadian rhythm.

The central biological clock in the brain, residing in the hypothalamus, manages this daily rhythm by responding to environmental cues, the most influential of which is the light-dark cycle. These cues help to synchronize our internal process precisely with the external world, ensuring optimal functioning.

Types of Biological Rhythms

  • Circadian rhythm: Roughly 24-hour cycle regulating sleep-wake patterns, hormone release, and metabolism.

  • Circannual rhythm: Seasonal cycle influencing breeding, migration, and hibernation in some animals.

  • Ultradian rhythms: Cycles shorter than 24 hours, such as sleep cycles and hormone fluctuations. Learn more about ultratidian rhythms here.

  • Infradian rhythms: Cycles longer than 24 hours, such as menstrual cycles and molting cycles.

How Biological Rhythms Work

At the core of these biological fluctuations is a system of internal clocks that collectively orchestrate the daily activities of our body. These internal clocks, regulated by a group of genes, interact with proteins to produce a self-sustained rhythm that can persist even without external cues.
It’s a complex system where the production of proteins is constantly shut down and rebuilt, creating a cycle that repeats over roughly 24 hours. This cycle, known as a feedback loop, ensures that the body’s various processes are kept in reliable time.

Types of Disruptions

Disruptions to biological rhythms can have severe implications on our health, including:

How to Maintain a Healthy Biological Rhythm Through Light Therapy Glasses?

Light therapy glasses are very effective against conditions that are disrupting the body’s natural biological rhythms. To learn more on their benefits, check out our detailed FAQ on the topic.

Related Definitions

CIRCADIAN HEALTH Sleep Biological Rhythms Circadian Rhythm