Archive for February 2009
The wise words of Wilse Webb, a prominent sleep researcher recently said.
So, question of pose: How long can humans stay awake?
The experiemental answer to this question is 264 hours (about 11 days). In 1965, Randy Garder, a 17 year-old high school student, set this apparent world-record for a science fair. Several other normal research subjects have remained awake for eight to 10 days in carefully monitored experiments. None of these individuals experienced serious medical, neurological, physoiological or psychiatric problems.
On the other hand, all of them showed progressive and significant deficits in concentration, motivation, perception and other higher mental processes as the duration of sleep deprivation increased. Nevertheless, all experimental subjects recovered to relative normality within one or two nights of recovery sleep. Other anecdotal reports describe soldiers staying awake for four days in battle, or un-medicated patients with mania going without sleep for three to four days.
The more difficult answer to this question revolves around the definition of “awake.” As mentioned above, prolonged sleep deprivation in normal subjects induces altered stated of consciousness ( often described as “microsleep”), numerous brief episodes of overwhelming sleep, and loss of cognitive and motor functions. We all know the dangerous, drowsy driver, and have heard about drowsy flyers crashing planes because they fell asleep while flying. RandyGardner was “awake” but basically cognitively dysfunctional at the end of his ordeal.
In certain rare human medical disorders, the question of how long people can remain awake raises other surprising answers, and more questions. Morvan’s fibrillary chorea or Morvan’s Syndrome is characterized by muscle twitchings, pain, excessive sweating, weight loss, periodic hallucinations, and severe loss of sleep ( agrypnia ). Michel Jouvet and his colleagues in Lyon, France, studies a 27 year-old man with this disorder and found he had virtually no sleep over a period of several months. During that time he did not feel sleepy or tried and did not show any disorders of mood, memory, or anxiety. Nevertheless, nearly everynight between 9:00 and 11:00 p.m., he experienced a 20 to 60-minute period of auditory, visual, olfactory and somesthetic (sense of touch ) hallucinations, as well as pain and vasoconstriction in his fingers and toes. In recent investigations, Morvan’s Syndrome has been attributed to serum antibodies directed again by specific potassium (K+) channels in cell and nerve membranes.
So, to return to the orginal question, “How long can humans stay awake?” the ultimate remains unclear. Despite studies, there are no reports that sleep deprivation per se has killed any humab ( excluding accidents and so forth ). Indeed, the U.S. Departmend of Defense has offered research funding for the goal of sustaining a fully awake, fully functional “24/7″ soldier, sailor, or airman. Future warriors will face intese, around the clock fighting for weeks at a time. Will bioengineering eventually produce genetically cloned soldiers and citizens with a variant of Morvan’s Syndrome who need no sleep but remain effective and happy? I hope not. A good nights sleep is one of life’s blessings.
As Coleridge wrote years ago, “Oh sleep! It is a gentle thing, beloved from pole to pole.”