Sleep Timing and Duration in Indigenous Villages with and Without Electric Lighting on Tanna Island, Vanuatu

Resource type
Date created
2019-11-21
Authors/Contributors
Abstract
It has been hypothesized that sleep in the industrialized world is in chronic deficit, due in part to evening light exposure, which delays sleep onset and truncates sleep depending on morning work or school schedules. If so, societies without electricity may sleep longer. However, recent studies of hunter-gatherers and pastoralists living traditional lifestyles without electricity report short sleep compared to industrialized population norms. To further explore the impact of lifestyles and electrification on sleep, we measured sleep by actigraphy in indigenous Melanesians on Tanna Island, Vanuatu, who live traditional subsistence horticultural lifestyles, in villages either with or without access to electricity. Sleep duration was long and efficiency low in both groups, compared to averages from actigraphy studies of industrialized populations. In villages with electricity, light exposure after sunset was increased, sleep onset was delayed, and nocturnal sleep duration was reduced. These effects were driven primarily by breastfeeding mothers living with electric lighting. Relatively long sleep on Tanna may reflect advantages of an environment in which food access is reliable, climate benign, and predators and significant social conflict absent. Despite exposure to outdoor light throughout the day, an effect of artificial evening light was nonetheless detectable on sleep timing and duration.
Document
Published as
Smit, A.N., Broesch, T., Siegel, J.M. et al. Sleep timing and duration in indigenous villages with and without electric lighting on Tanna Island, Vanuatu. Sci Rep 9, 17278 (2019). DOI: 10.1038/s41598-019-53635-y.
Publication title
Sci Rep
Document title
Sleep timing and duration in indigenous villages with and without electric lighting on Tanna Island, Vanuatu
Date
2019
Volume
9
Issue
17278
Publisher DOI
10.1038/s41598-019-53635-y
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Copyright is held by the author(s).
Scholarly level
Peer reviewed?
Yes
Language
Member of collection
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s41598-019-53635-y (1).pdf 4.84 MB