Biphasic sleep left me feeling relaxed, meditation prone, inspired, and really, really socially deprived.
In this article I’ll tell you why I chose to spend two weeks of my life exploring this ancient type of sleep, the history behind it, what I liked about polyphasic sleep, and what annoyed me.
What Is Biphasic Sleep?
Biphasic sleep is a variety of polyphasic sleep where, instead of sleeping once per night, your evening sleep period is divided between two sleep segments and the wakeful interlude between them.
It may sound like some kind of crazy new-age idea or productivity strategy, but polyphasic and biphasic sleeping patterns go back to before humans had evolved into humans. It was the rule – rather than the rare exception it is today – for the millions of years before nighttime lighting became widespread in the 1600s A.D.
Until a few decades ago, researchers assumed human sleep patterns were largely unique among mammals on this planet. We’re almost the only ones that konk out for 7-9 hours at a time and then spend the rest of our days in periods of undivided wakefulness, the thinking went.
Daytime naps have always been around, of course, but this was assumed to be something of an exception rather than the rule.
But the myth of the human monophasic sleep pattern evaporates when you look beyond the developed world, particularly among extant hunter gatherer tribes that have a limited ability to light up their night time world.
For instance, anthropologist Paul Bohannan, who studied the Tiv of Nigeria in the 1960s, noted that “At night, they wake when they will and talk with anyone else awake in the hut.” The Tiv also refer to “first sleep,” and “second sleep,” as two distinct phases1.
Other tribes around Africa, such as the !Kung of Botswana and the Efe of Zaire, are noted for the fluidity of their sleeping patterns. Most would be considered polyphasic sleepers, with some having multiple blocks at night and others having one or more blocks in the day.
Literary and historical references of the ancient world, from Homer and Virgil to Canterbury Tales, are littered with references to first and second sleep, and mention some of the things people did between them2.
[pullquote align=”full” cite=”” link=”” color=”” class=”” size=””]“Time’s grateful hour, was soothing care with first sleep’s heavenly power: And Hector sought my dreams – a sea of tears disgraced and dragged, the gory dust besmears.” -Virgil, The Aeneid.[/pullquote]
But how exactly did humans in the developed world get away from this sleeping pattern, and do we still posses the ability to experience it?
Human Biphasic Sleep Experiments:
Historically, the winter sun only lit up the sky for 10 hours a day or less in temperate regions, and then people were left in relative darkness. With a limited ability to light up the night, ancient peoples often drifted off to sleep soon after dusk. But light is known to have significant affects on human health and hormonal balance, so how might their sleep have been facilitated or altered by the lack of light?
In 1992, research Thomas Wehr attempted to artificially recreate this 10-hour photoperiod and see how it would affect humans hormonally and in terms of real-world sleep patterns 3.
He let his seven subjects wander about freely outside or in indoor lighting for 10 hours, but afterward confined them to a totally dark room with a bed. They were not allowed to listen to music or do anything strenuous, but instead were instructed to relax or sleep as they wished. This went on for four weeks.
After a few days, the subjects’ sleeping patterns morphed. In place of one unbroken sleep period, they had two similar-length periods of sleep divided by 1-3 hours of wakefulness in the middle of the night. Melatonin production was also ramped up for a considerably longer portion of each day, facilitating their ability to sleep for such a large portion of the day.
My Biphasic Sleep Experiment
I decided to copy Wehr’s experiment in my own home for two weeks and see what would happen.
I was not motivated by a desire for improved productivity (which is why many people try polyphasic sleep trials), but simply because I was curious about this pattern, which was part of the human experience for so long. If anything, I knew it would make me dramatically less productive. I was also curious to see how it might affect my waking life, levels of alertness, etc.
I was able to reproduce the biphasic sleep pattern by not putting on any lights once the sun went down, and not putting them back on till it came back up (Roughly 10 hours of light each day). I mostly laid in bed, or sat up and meditated. I didn’t allow myself to do anything that might be stimulating, like listen to an audiobook or music.
After a few days I usually drifted off to sleep by 7 p.m., woke up for 1-3 hours in the middle of the night, then drifted off to sleep again till dawn.
During the 1-3 hours that I was awake each night, I found myself in a state of of deep relaxation. It was an odd kind of half life between my waking and slumbering lives, and a place that I was happy to be visiting because it left me so mellow.
In years past I periodically suffered from insomnia, which sometimes also lead me to wake up in the middle of the night. Biphasic sleep leads to a dramatically different experience, however. Insomnia leaves you feeling anxious and annoyed, but the early-morning wake time you encounter during biphasic sleep seems like a generally welcome interlude.
On several of my biphasic nights I seemed to meander between a half-slumbering reverie and what seemed like divine inspiration, with ideas for writing projects and videos flooding my head. Some of them seemed half baked in the sober light of morning, but many were genuinely good. Although I’d been mulling some business reforms for some time, the idea to create Renaissance Humans was actually born out of one of those nights. I sometimes hook into a similar flow of ideas during the day, but the hook-up is sporadic, and I was very happy to get a nighttime connection to wherever it is inspiring ideas come from.
The twilight time between biphasic sleep one and two seems a particularly effective time to meditate. While I don’t think it’s going to turn an undeveloped meditator into a master, there does seem to be a certain quiet of the mind in the middle of the night. However, I’ve long felt thoughts gain momentum as you continue to think them, and before biphasic sleep my best meditations were usually done early in the morning right after waking up. So perhaps its less about the hormonal situation between sleep one and two and more that your mind hasn’t started racing yet, as is usually also the case when you first wake up in the morning.
Several people have asked me if my biphasic sleep experiment lead to lucid dreams, or dreams where you’re, “awake,” and able to control the dream to some extent.
When I was in college I spent about a month following a program I’d found somewhere and was eventually able to control my dreams almost every night, but it honestly just wasn’t all that entertaining and I stopped doing it. The ability to do it didn’t randomly return during the two of biphasic sleep weeks.
However, I did have a pretty interesting dream experience, and what might be the only time I literally made my dreams come true.
I dreamed that I was holding a flyer over my head in a partner acrobatics move that’s called, “high bird,” which was made famous by the movie, “Dirty Dancing.” But I dreamed that I was holding the flyer above me with just a single arm, which I’d never done before and hadn’t even seen. I also was painting a fence yellow with my free hand, oddly. I woke up determined to do it, and a few days later I gave it a shot.
Turns out I can do one!
Biphasic Sleep Downsides:
In a world without electronic devices, lights, and evening social activities, I could see myself falling into this sleeping pattern. It brought a nice rhythm to my life that’s probably far more natural than what I’m used to. But honestly, I couldn’t make this stick long term while living in civilization.
The biphasic sleeping experiment left me vaguely irritated at dusk most days because I was usually wrapped up in doing something that I had to stop working on because the sun was going down. I also passed on several social activities I would have enjoyed that would have brought me out, exposed me to lights, and kept me stimulated.
Since I work at home during the day, this ended up leaving me pretty socially deprived.
There were no particular improvements in feelings of alertness or being rested compared to a regular night with 8-9 hours of sleep compressed into one block. If there had been, I would have had a harder decision to make.
Biphasic Sleep: Going Forward
While a fun experiment, and even enjoyable in many ways, I feel like this would take more from my life than it would add. During camping trips and vacation time in rural settings I may revert to this way of sleeping periodically, but while I’m in civilization I’ll probably keep using lights and sleeping in solid blocks.
Bohannan, Paul. “Concepts of Time Among the Tiv of Nigeria”. Southwestern Journal of Anthropology 9.3 (1953): 251–262.↩
Ekirch, Roger A. “Sleep We Have Lost: Pre-industrial Slumber in the British Isles” The American Historical Review. V 106. Issue 2. Pages 343 – 386.↩
Wehr, Thomas A. In short photoperiods, human sleep is biphasic. Journal of Sleep Research Volume 1, Issue 2, pages 103–107, June 1992.↩