Midnight looks different in different time zones across the globe. In the United States and most other industrialized societies, people are checking their smartphones and thinking about turning off the lights and getting some much-needed shut-eye. But in the developing world, people are likely getting up for a cup of tea. Having slept four hours, they are now taking a natural #sleep break before settling down for a second phase of slumber.
“If we look at cultures all around the world, we see that sleep is interpreted in very different ways between different cultures and between the western culture and the more traditional cultures,” says Dorothy Bruck, an Australian psychology professor who is one of many researchers studying the impact of culture on sleep.
What accounts for these different sleep patterns? In part, we have Thomas Edison to thank. Before the advent of artificial electrical light, human beings for the most part arose and went to sleep with the sun. But they also engaged in what’s called biphasic sleep, sleeping for a four-hour block, waking for a spell, then retiring again until daybreak.
Some cultures continue to practice biphasic sleep, such as the rural Toraja of Indonesia, who continue to rise at various times through the night. In western societies, however, monophasic sleep—sleeping for a single uninterrupted period—is the norm.
Even in the industrialized world, there isn’t uniformity as to how many hours a night different nations tend to sleep. The #National Sleep Foundation conducted a Bedroom Poll in 2013 that quantified sleep patterns among six countries in the industrialized west. The Japanese were identified as logging the fewest hours of sleep per weeknight, with an average of 6 hours and 22 minutes, with the United States following close behind at 6 hours and 31 minutes. Mexicans slept the most per weeknight, with a national average of 7 hours, 6 minutes, with Canadians and Germans both sleeping just over 7 hours a night.
Another difference in sleeping patterns across cultures is the custom of afternoon naps or siestas, which remain prevalent in countries as diverse as Greece, Italy, the Philippines, Mexico, and Nigeria.
And some of these siestas happen at work. Even though the Japanese log the fewest hours of sleep per night, Japanese workers make up for this sleep deficit by practicing inemuri, a nap taken at one’s desk during the work day.
Indeed, in case you needed further evidence for the different ways sleep are interpreted across the world, inemuri is viewed in Japan with pride, a sign of one’s commitment to work, to the extent of sacrificing sleep. Imagine being proud of falling asleep at work!
But the practice has been making inroads in the U.S., and is being taken up by employees at some tech companies like Google, where employees are given the opportunity to nap at work.