Biphasic Sleep
February 24th, 2011 § Leave a Comment
Humans’ natural sleep cycles are biphasic, meaning sleep is separated into two parts. In a natural environment with no artificial light and mostly equal amounts of night and day (think near the equator), sleep happens shortly after the sun goes down, followed by an hour or so of calm wakefulness around mid-night, followed by another bout of sleep, which is finally broken after dawn.
Here is a brief TED talk by Jessa Gamble.
Anecdotally, I don’t remember having any meditative periods that break up two cycles of sleep.
I have experienced the wonderful feeling of deep sleep followed by extreme wakefulness. The most notable of these experiences generally happen during the summer, and more so during a camping expedition.
On a trip to Belize that involved little to no artificial light (and fairly even amounts of day/night), shortly after sundown profound sleepiness set in.
Mark’s Daily Apple has more.
