Moonlight and Sleep (05-18-21)

Casiraghi and colleagues’ work indicates how tightly the experiences of all humans are tied to stimuli in the natural world.  The researchers used “wrist actimetry to show a clear synchronization of nocturnal sleep timing with the lunar cycle in participants living in environments that range from a rural setting with and without access to electricity in indigenous Toba/Qom communities in Argentina to a highly urbanized postindustrial setting in the United States.  Our results show that sleep starts later and is shorter on the nights before the full moon when moonlight is available during the hours following dusk.  Our data suggest that moonlight likely stimulated nocturnal activity and inhibited sleep in preindustrial communities and that access to artificial light may emulate the ancestral effect of early-night moonlight.”

Leandro Casiraghi, Ignacio Spiousas, Gideon Dunster, Kaitlyn McGlothlen, Eduardo Fernandez-Duque, Claudia Valeggia, and Horacio de la Iglesia.  2021.  “Moonstruck Sleep: Synchronization of Human Sleep with the Moon Cycle Under Field Conditions.”  Science Advances, vol. 7, no. 5, eabe0465, DOI: 10.1126/sciadv.abe0465