title: Circadian rhythms. 1: Physiology.
abstract: Circadian rhythms are repeated psychophysiological patterns of the body. They are endogenously controlled and environmentally modified and are therefore a sociopsychophysiological phenomenon. Subjectivity of circadian rhythms occurs with relation to the individual circadian parameters and also within different individuals. The hypothalamus appears to be the master clock synchronizing the free-running rhythms of individual circadian control centres. Internal synchronisation occurs when the rhythms are within their homeostatic ranges.
authors.forename: J
authors.initials: J
authors.lastname: Clancy
authors.forename: A
authors.initials: A
authors.lastname: McVicar
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology*; D006706:Homeostasis; D006801:Humans; D010870:Pineal Gland / Q000502:physiology; D012160:Retina / Q000502:physiology; D012890:Sleep / Q000502:physiology; D014851:Wakefulness / Q000502:physiology