In his article, “Ancient Sleep in Modern Times,” Walter A. Brown, professor of psychiatry, unveils an apparently unknown fact about the nature of human sleep, as revealed by independent research in both sleep psychology and history. The forgotten fact is that humans, like many other mammals, used to have a natural interruption in their night’s sleep, according to the historical research, and that that interruption is a natural result of circadian rhythms, according to the sleep psychology research.
The historian A. Roger Ekirch published a text in 2005 entitled, At Day’s Close: Night in Times Past. In that book, Ekirch reveals that it was entirely common for pre-industrial humans to have an interruption in their night’s sleep that could last several hours, in which they quietly contemplated their dreams, did household chores, visited family or friends, or had sex. According to the historical research, people used to retire earlier, within an hour after sunset, sleep for approximately four hours, wake up for a few hours, and then sleep for another four hours. Completely independent of this historical research, research in the field of sleep psychology, notably in the studies of Thomas A. Wehr, then of the National Institute of Mental Health, concluded that to break a night’s sleep into two sessions is more “in tune” with the body’s natural circadian rhythms.
Together, the two research efforts seem to yield the conclusion that it would be more natural for humans in the present day to break their sleep in the same way their ancestors did. However, while that may be the natural urge of biology, the environment in which sleep occurs differs greatly from that of a few short centuries ago. In modern times, the day is protracted by artificial light, and the demands of society’s common schedule often require later going to bed and earlier rising than the “natural” system would allow.
This research has direct application to discussions in class, namely those pertaining to the circadian rhythms that govern the human sleep cycle, and also the discussions of insomnia. The article directly advances the opinion that what many perceive as insomnia when waking in the middle of the night for several hours may not be that at all, but, rather, that it is a sleep habit inherited from millennia of human who slept exactly that way, and so not a disorder of any kind.
I find this article extraordinarily interesting, as someone who often feels under-rested. While I am not aware of ever having interrupted my sleep in the manner described, I am always curious to discover ways to improve my sleep habits to feel better rested throughout the day. Unfortunately, the article makes it quite clear that there is little reasonable expectation that this more natural sleep program could be implemented in the modern world, with its different environment and demands.