Bipolar mood cycles associated with lunar entrainment of a circadian rhythm

Transl Psychiatry. 2018 Aug 13;8(1):151. doi: 10.1038/s41398-018-0203-x.


In bipolar disorder, episodes of depression and mania are associated with dramatic disturbances in sleep, which experiments show are likely to contribute to the pathogenesis of the episodes. A recent finding that 18 patients' manic-depressive cycles oscillated in synchrony with biweekly surges in amplitude of the moon's tides provided a clue to the cause of the sleep-disturbances. Analyses of one of the patients' sleep-wake cycles suggest that his mood cycles arose when a circadian rhythm that normally is entrained to dawn and controls the daily onset of wakefulness became entrained instead to 24.8-h recurrences of every second 12.4-h tidal cycle. The finding provides the basis for a comprehensive description of the pathogenesis and pathophysiology of the mood cycle.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Affect
  • Bipolar Disorder / physiopathology*
  • Bipolar Disorder / psychology*
  • Circadian Rhythm / physiology*
  • Humans
  • Male
  • Middle Aged
  • Moon*
  • Sleep / physiology*
  • Sleep Wake Disorders / physiopathology
  • Wakefulness