PDA

View Full Version : Sleep Deprivation



joe yang
6th December 2001, 20:54
Kwan Chung Nihm says we need proper diet, proper exercise and proper sleep for proper health. But, he claims, two out of three isn't bad. My question, sleep debt appears to be inevitable, does meditation help?

Joseph Svinth
7th December 2001, 07:30
To a large extent, what constitutes "sleep deprivation" depends on what you're doing. See http://www.emedicine.com/neuro/topic444.htm :

"As the function of sleep has not been fully determined, the absolute number of hours necessary to fulfill its function is still unknown. Some individuals claim full effectiveness with only 3-5 hours of sleep per night, while some admit needing at least 8 hours of sleep per night (or more) to perform effectively. Sleep deprivation is best defined at this point by group means and in terms of the tasks impaired.

With decreased sleep, higher-order cognitive tasks are affected early and disproportionately. Tests requiring both speed and accuracy demonstrate considerably slowed speed before accuracy begins to fail. Total sleep duration of 7 hours per night over 1 week has resulted in decreased speed in tasks of both simple reaction time and more demanding computer-generated mathematical problem solving. Total sleep duration of 5 hours per night over 1 week shows both decrease in speed and the beginning of accuracy failure.

Total sleep duration of 7 hours per night over 1 week leads to impairment of cognitive work requiring simultaneous focus on several tasks. In driving simulations, for example, accidents increase progressively as total sleep duration is decreased to 7, 5, and 3 hours per night over 1 week. In the same simulations, 3 hours total sleep duration was associated with loss of ability to simultaneously appreciate peripheral and centrally presented visual stimuli, which could be termed as a form of visual simultanagnosia and peripheral visual neglect.

In tasks requiring judgment, increasingly risky behaviors emerge as the total sleep duration is limited to 5 hours per night. The high cost of an action seemingly is ignored as the sleep-deprived individual focuses on limited benefit. "

For more Army medical research on the topic of sleep deprivation, see http://wrair-www.army.mil/depts/behavbio/bbhp.htm . The Ranger School is a favorite study area, as during the 58-day course, the lads average 3.2-3.6 hours of sleep per day. "This sleep was not accrued in a single sleep period, but rather occurred as several naps during each 24 hour period. Anecdotally, cognitive performance in ranger candidates is marginal, with frequent episodes of what the rangers call 'droning' -- i .e., the candidates can put one foot in front of another and respond if challenged, but have difficulty grasping their situation or acting on their own initiative."

Anyway, my non-medical opinion is that if you are getting less than 5 hours of sleep a day and have time to meditate, you really should be spending it napping. This isn't as heretical as it sounds, either. For example, Koichi Tohei readily admitted that a lot of the time people saw him sitting Zazen, he was really sleeping.

Jon S.
8th December 2001, 07:33
I saw a show on TV a while ago which said (to the best of my recollection) that when faced with the prospect of very little sleep, to function effectively the best thing to do is take short naps on a frequent basis. I seem to recall that emergency workers were the subject of some studies, and it was determined that with a 15 minute nap every four hours, they could potentially operate indefinately.

I'd bet that meditation could be useful for such things as helping you to stay more focused, but I doubt it would remove fatigue - unless you managed to reach a really deep state (probably something like sleep or what's known as lucid dreaming). Of course this is just a guess. In my own experiences when deprived of sleep, when I sat down to meditate I fell asleep.

I also saw a show once on people who go into trances. I think it said that they must sleep a lot after doing so. It certainly seems that different states of mind affect the body's need for sleep.

Jon Small