If it seems to you that the phases of the moon affect your sleep, then most likely you are right. American scientists have found out that the Earth's satellite causes not only sea tides. On the eve of the full moon, people go to bed later and sleep less — study jpg» />
98 residents of three communities of the Toba Indian people in Argentina took part in a study by the University of Washington. One community uses electricity all the time, another a few hours a day, and a third has no artificial lighting at all. The Indians were equipped with portable devices that tracked sleep patterns over two lunar cycles. One lunar cycle is 29.5 days.
At the same time, scientists conducted the same experiment with the participation of 464 students from Seattle, a modern and well-lit metropolis at any time of the day.
“Moonlight is very bright to the human eye, and it is reasonable to assume that in the absence of other sources of illumination, it can play a significant role in modulating human nighttime activity. We decided to test the hypothesis that in communities without access to electricity, people have increased nighttime activity during the full moon,” the study authors wrote.
On average, participants from the experiment from the Indian community went to bed for 30 minutes later and slept 50 minutes less on the night before the full moon, when the moonlight is especially bright. The scientists compared these data with the results of a study involving young people from Seattle and were surprised to find that their sleep patterns changed in much the same way. Moreover, on the eve of the full moon, the townspeople went to bed even later and the duration of their sleep was even shorter than that of the inhabitants of the Indian community.
According to scientists, this effect appeared in the pre-industrial era, when people tried to use the period of maximum bright moonlight for their occupations, and entrenched in the course of evolutionary adaptation.
«Our findings strongly suggest that human sleep is still synchronized with the phases of the moon, regardless of ethnic and sociocultural background,» the authors of the study concluded.