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CENTER FOR APPLIED COGNITIVE STUDIES (CentACS)
CentACS reports that "studies show that the length of sleep is not what causes us to be refreshed upon waking. The key factor is the number of complete sleep cycles we enjoy. Each sleep cycle contains five distinct phases, which exhibit different brain- wave patterns. For our purposes, it suffices to say that one sleep cycle lasts an average of 90 minutes:
- 65 minutes of normal, or non-REM (rapid eye movement), sleep
- 20 minutes of REM sleep (in which we dream)
- Final 5 minutes of non-REM sleep.
The REM sleep phases are shorter during earlier cycles (less than 20 minutes) and longer during later ones (more than 20 minutes). If we were to sleep
completely naturally, with no alarm clocks or other sleep disturbances, we would wake up, on the average, after a multiple of 90 minutes--for example, after 4
1/2 hours, 6 hours, 7 1/2 hours, or 9 hours, but not after 7 or 8 hours, which are not multiples of 90 minutes. In the period between cycles we are not
actually sleeping: it is a sort of twilight zone from which, if we are not disturbed (by light, cold, a full bladder, noise), we move into another 90-minute
cycle. A person who sleeps only four cycles (6 hours) will feel more rested than someone who has slept for 8 to 10 hours but who has not been allowed to
complete any one cycle because of being awakened before it was completed.... "
2006 NATIONAL INSTITUTES OF HEALTH CONSENSUS CONFERENCE
Robin Lloyd of Live Science reports that at the 2006 National Institutes of Health Consensus Conference, experts agreed, according psychiatry professor Daniel Kripke of the University of California, San Diego on the following recommendations for obtaining optimum sleep value:
- Do not take sleeping pills. This includes over-the-counter pills and melatonin.
- Don't go to bed until you're sleepy. If you have trouble sleeping, try going to bed later or getting up earlier.
- Get up at the same time every morning, even after a bad night's sleep. The next night, you'll be sleepy at bedtime.
- If you wake up in the middle of the night and can't fall back to sleep, get out of bed and return only when you are sleepy.
- Avoid worrying, watching TV, reading scary books, and doing other things in bed besides sleeping and sex. If you worry, read thrillers or watch TV, do that in a chair that's not in the bedroom.
- Do not drink or eat anything caffeinated within six hours of bedtime.
- Avoid alcohol. It's relaxing at first but can lead to insomnia when it clears your system.
- Spend time outdoors. People exposed to daylight or bright light therapy sleep better.
A six-year study Kripke headed up of more than a million adults ages 30 to 102 showed that people who get only 6 to 7 hours a night have a lower death rate than those who get 8 hours of sleep. The risk from taking sleeping pills 30 times or more a month was not much less than the risk of smoking a pack of cigarettes a day, he says.
So what happens when you don't have time for even 6 hours of sleep? Surely you can't go without sleep? Without adequate rest, the brain's ability to function quickly deteriorates. The brain works harder to counteract sleep deprivation effects, but operates less effectively: concentration levels drop, and memory becomes impaired.
Similarly, the brain's ability to problem solve is greatly impaired. Decision-making abilities are compromised, and the brain falls into rigid thought patterns that make it difficult to generate new problem-solving ideas. Insufficient rest can also cause people to have hallucinations. Other typical effects of sleep deprivation include:
- depression
- heart disease
- hypertension
- irritability
- slower reaction times
- slurred speech
- tremors
Bеcause the amount and quality of the sleep we get affects our hormone levels, namely our levels of leptin and ghrelin, many physiological processes that depend on these hormone levels to function properly, including appetite, are affected by our sleep.
While leptin is a hormone that affects our feelings of fullness and satisfaction after a meal, ghrelin is the hormone that stimulates our appetites. When
you suffer from sleep deprivation, your body's levels of leptin fall while ghrelin levels increase. This means that you end up feeling hungrier without
really feeling satisfied by what you eat, causing you to eat more and, consequently, gain weight.
POLYPHASIC SLEEP
Polyphasic sleep is a term used to describe several alternative sleep patterns intended to reduce sleep time to 2-6 hours daily in order to achieve a better quality of sleep. This is achieved by spreading out sleep into short naps of around 15-30 minutes throughout the day, and in some variants, a core sleep period of a few hours at night.
The term "polyphasic sleep" itself refers only to the practice of sleeping multiple times in a 24-hour period (usually, more than two, in contrast to "biphasic sleep") and does not imply any particular schedule.
Uberman's Sleep
In application, Uberman's sleep schedule is likely to be the most widely known type of polyphasic sleep, and also the most strict. It consists of six naps of 20-25 minutes each, occurring four hours apart throughout the day. This is also the closest schedule to the type that has been studied by Claudio Stampi in connection with long-distance solo boat races. Claudio Stampi advocates polyphasic sleep as a means of ensuring optimal performance in situations where extreme sleep deprivation is inevitable (e.g. to improve performance in solo sailboat racers), but Stampi does not advocate the polyphasic sleep as a lifestyle.
Core Sleep
"Core sleep" is a variant of Uberman that adds a block of sleep, usually several hours, to the Uberman schedule, replacing one or two naps. (This term is also sometimes used to describe accidental oversleep by someone following Uberman, though one will more likely see the term "crash", and occasionally "reboot".) Another variant is called Everyman sleep schedule.
Buckminster Fuller advocated Dymaxion Sleep, a regimen consisting of 30 minute naps every six hours. A short article was published about this schedule in the October 11, 1943 issue of Time Magazine. According to this article, he followed this schedule for two years, but after that had to quit because "his schedule conflicted with that of his business associates, who insisted on sleeping like other men."
Scientists say that a successful midday nap depends on two things: timing and (no kidding) caffeine consumption. Experiments performed at Loughborough University in the UK showed that the sleep-deprived need only a cup of coffee and 15 minutes of shut-eye to feel amazingly refreshed.
1. Right before you crash, down a cup of java. The caffeine has to travel through your gastro-intestinal tract, giving you time to nap before it kicks in.
2. Close your eyes and relax. Even if you only doze, you'll get what's known as effective microsleep, or momentary lapses of wakefulness.
3. Limit your nap to 15 minutes. A half hour can lead to sleep inertia, or the spinning down of the brain's prefrontal cortex, which
handles functions like judgment. This gray matter can take 30 minutes to reboot.
