Artificial light can affect the quality of sleep a person gets at night, a study by researchers found.
In a study involving indigenous tribes of hunter-gatherers from Chaco region in northeastern Argentina, researchers from the University of Washington, Harvard, Yale and Argentina's University of Quilmes have documented for the first time the link between access to artificial light and the amount of sleep an individual gets at night.
For the study, researchers observed two communities composed of hunter-gatherers that have similar sociocultural and ethnic backgrounds.
The purpose of the study, which appeared in the journal Biological Rhythms, was to see if electricity can affect the sleep cycle during summer and winter.
In the Chaco region, two indigenous Toba/Qom communities, live around 50 kilometers from each other. The first community has free access to electricity for 24 hours and anyone can just turn the lights on as they wish.
On the other hand, the second community does not have access to electricity and only rely on natural light, as reported in Science 2.0. With a wrist-fitted device, researchers were able to track the participants' sleep-wake cycles.
The study found that the community that has electricity access slept around 40 minutes less compared with the other community during summer. Moreover, the community with electricity slept about one hour less during winter compared with the other community.
"Our findings are consistent with the hypothesis that access to electricity has allowed humans to extend the evening light hours, thereby delaying the time of sleep onset and reducing daily sleep duration," the report reads.
According to Eduardo Fernandez-Duque, co-author of the study and biological anthropologist from Yale University, the study suggests that early humans may have had more time to rest compared with most people in modern societies.
The report also explained that access to different sources of artificial lighting and having the ability to create artificial lighting must have served as important factors that reduce sleep in industrialized societies.
