Wednesday, January 30, 2008

...and miles to go before I sleep...

A point to ponder - why do we sleep at night, and not really at day? Why is it that sleeping is necessary? Why would one feel fresh after a good night sleep?

Not that these are questions that I would want answers to, in order to get enlightened! It's just that, I was trying to sleep last night, and just could not! I would have had what, maybe three hours of sleep last night, and still I am as fresh as ever. And many-a-times, even when I get as much as 14 hours of sleep at a stretch, I can feel uneasiness creeping into me.

I tend to feel good about the fact that the work I do is what I really like to - and the best part is that the arrangement that I work in suits my time and the things I want to do too. This morning itself, I was having this conversation with P (P's a friend of N, with whom I am staying right now), and I felt very proud telling her that I work in an arrangement that suits me, and I do work when I want to - all this enables me to sleep when I want to, and as much as I want to. Though I said all this (I mean it too!), but in retrospect, I can't still figure out why my sleeping cycle is like that! Why is it that I normally can catch sleep only after 3 o'clock in the morning (Is it that I am meant to stay in the vast lands of Switzerland!); why is it that there is hardly any correlation between the number of hours I sleep and my energy levels after getting up.

Obviously there is the question of whether any sleep is needed or not - No one has proven that humans needs sleep to live, obviously. How do you keep someone awake? When you get tired enough you can sleep through anything. More to the point, killing someone for science is unethical.. but an experiment has been done on mice, where they were left on a constantly turning turntable, with food and water, for several days. The constant slow spinning made it impossible for them to sleep, and after a few days, they died. I don't know how close we are to mice family, but I sure think I'll sleep!

There have been studies that 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); and a 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, nature's call, 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.

It explains why, when I get 8 hours of sleep I feel tired and groggy, or when I get 4 hour of sleep, I can barely wake up. As human beings, we should know about this fact, as everyone always says "get your 8 hours". Yet some people fare better than others. Why is that? Probably because the more rested people are actually getting closer to 7.5, or 9 hours, while the 8 hour folk feel constantly unrested.

I now know when my alarm should ring! And now I know, why those 3 hours of sleep last night were more than enough!

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