PMID: 16619063Apr 19, 2006Paper

Rhythms, depressions and light

Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række
Anders Johnsson, Johan Moan

Abstract

Many aspects of life in plants, animals and humans are controlled by light. Endogenous, so-called circadian rhythms in the body deviate from the exact 24-hour day and have typically a period of around 25.5 hours in man. Normally these rhythms adapt to the external 24-hour day-and night changes but under constant conditions the rhythms can free run. Many studies show how important the interplay between light and the circadian rhythms are for man as well as for other organisms. The control of these rhythms by light is mediated via the retina and the melatonin system in man. The adaptation of the rhythms is very important in shift work, in rapid jet lag travels over time zones, etc. Organisms often use the circadian rhythm to determine the length of day and of night, a feature that has given rise to the term biological clocks. A biological clock provides possibilities to determine the proper time for physiological processes to start in plants and animals (flowering, hibernation etc). The importance of light and circadian rhythms for seasonal affective disorders and manic-depressive disorders is also discussed. For several organisms one has now been able to specify genes that determine the period of the clocks. The rhythmic physiol...Continue Reading

Related Concepts

Related Feeds

Bipolar Disorder

Bipolar disorder is characterized by manic and/or depressive episodes and associated with uncommon shifts in mood, activity levels, and energy. Discover the latest research this illness here.

Related Papers

CNS Drugs
Pierre Schulz, Thierry Steimer
Journal of Genetics
Manjunatha TVijay Kumar Sharma
Nihon rinsho. Japanese journal of clinical medicine
Hitoshi Ando, Akio Fujimura
© 2022 Meta ULC. All rights reserved