It doesn’t incite concern for it’s part of daily life. Yet, if one were to think about it, sleep is a very strange phenomenon. Being asleep is closest one could get to experiencing death and being able to wake up to tell about it. Is it not strange that every day we are overcome by stupor which necessitates us to stop doing whatever we do and just fall unconscious: vulnerably and helplessly? Is it not terrifying that we completely lose passage of time and awareness of our surrounding when we are sleeping? How long eight hours pass in a instant and we don’t even have a clue where our life went then? Would you not be paranoid if you didn’t know what happened with you for those odd hours beyond your own control? This Onion articles tells it as it is. We’d be petrified if not for the fact that it is talking about night and sleeping. Yet, we don’t really think about it at all. Except, when an stranger from alien land displays shock about this strange habits of humans (and other species) and our nonchalance about it, as it did in a small story by Isaac Asimov.
Science has been proving that sleep is very useful for our body. It is so important, in fact, that you would die earlier if you didn’t sleep than if you didn’t eat. It helps us relax our body machine. It helps us digest (notice sour burps after long sleeplessness). It helps process and organize memories (lack of sleep results in loss of memory). It helps repair and maintain our body cells damaged during the day. Sleep occurs in roughly 90 minutes cycles of regular sleep and Rapid Eye Movement (REM) sleep. Brain repairs body in regular cycle and itself in REM cycle, where we are in very deep sleep. An opinion on internet suggests that if we sleep in multiples of 90 minutes, we may be able to avoid groggy eyes and wake up cheerful even after shorter sleep. There is no scientific confirmation of this. We know what sleep does, but we still don’t know why and how.
Why would sleep evolve through Darwinian evolution? What advantage could an being immovable, unaware and vulnerable over hours had over those who didn’t sleep? Intuitively, it fails logic. An specie which learned to sleep will soon be devoured by predators even if other which didn’t is slow or stupid (some links* on the topic). Yet, most animal species sleep, indicating that development of sleep must have occurred long ago in evolution tree.
What science hasn’t understood completely, and what has huge implication of our society, is the frequency of sleep. It somehow came to be understood that sleeping once a day during night is the right way. Modern biology has even told us about the required length for good sleep. Most of it is driven by industrial revolution and non-agrarian societies. However, what remains unexplored, is if sleeping twice a day for equal duration or any other combination of duration might work better. People have different personal experience on this one but I find that an hour nap in afternoon increases productivity of rest of day significantly. On a fanciful note, I had always wished that we had capacity to store sleep upfront when there is much time for later when there isn’t enough.
Next time when you hit the sack do ponder over our very little understanding of such an important and obscure phenomenon.
*This argument seems invalid to me because as Richard Dawkins tells in The Selfish Gene, it’s not survival of the fittest specie that is aimed towards by evolution but survival of the fittest gene.