Polyphasic sleep is a sleep pattern specification intended to compress sleep time to 2â€“5 hours daily. This is achieved by spreading out sleep into short naps of around 20â€“45 minutes throughout the day. This allows for more waking hours with relatively high alertness.
The method uses natural human sleep mechanisms to maximize alertness when sleep time needs to be minimized. However, it requires a rigid schedule which makes it unfeasible for most people. It can work well for people who cannot afford sleep (e.g. sailors).
The theory is that ordinary monophasic sleep consists of many phases, only a few of which are needed for survival. REM sleep, occurring quite late in the sequence, is commonly believed to be one such necessary phase. It is believed that after being deprived of sleep during an adjustment period, the brain will start to enter the required stages much quicker – with the result that each short nap consists almost solely of REM sleep. Some theories of sleep suggest that REM is largely responsible for the mental rejuvenation effects of sleep, but the role of REM sleep has in recent years been disputed. It has been documented that depriving rats of REM sleep specifically leads to death in 3 to 8 weeks (which doesn’t happen with depriving test animals of other specific sleep phases), but it has also been documented that humans survive without REM sleep. Since polyphasic sleepers get a lot of Stage 4 NREM and REM sleep, they may achieve higher alertness levels than those who do not know the art of catnapping.
Some critics of the theory have expressed concern about the possible long-term effects of suppressing the other sleep stages, although such effects have been undocumented as of yet. Some negative effects may be unrelated to this particular schedule, but more related to the general lack of sleep this method entails. It has been shown that a lack of sleep weakens the immune system, decreases the amount of growth hormone produced, and decreases the ability of the body to metabolize sugar. However, polyphasic sleep is different from unmanaged sleep deprivation, so it’s unclear whether these side effects would still be present.
Several famous people applied catnapping to a large extent. These include Leonardo da Vinci, Thomas Jefferson, Thomas Edison and Buckminster Fuller. Other figures said to be associated with polyphasic sleep experimentation include Nikola Tesla, Napoleon, and Winston Churchill. This method was also popularized on Seinfeld, where the character Cosmo Kramer attempted to adapt to a polyphasic sleeping pattern.
Boat racers use this technique to avoid dangers at sea. Astronauts use this technique during extended crises, and military personnel, especially marines, use this technique in training.
One of the leading advocates of polyphasic sleep research is Dr. Claudio Stampi (Founder and Director of the Chronobiology Research Institute in Boston, Massachusetts).