Amongst some of the things that amazes me most about the human body is our cycle of sleep and in addition to it the complex and intriguing phenomenon of dreams. When we sleep, we are in either of the two stages of REM or NREM. REM stands for Rapid Eye Movement, is the period of sleep when the eye is in a constant motion, while NREM is Non-REM as the name suggests when there is no movement activity. An ordinary sleep is in cycles of around 90 mins in which the major portion (about 70 mins) is the NREM sleep, the small REM portion is the one in which we are popularly supposed to have our dreams and other bizzare visual experiences. However dreams can occur in the other parts of the sleep as well. Researchers have done tremendous analysis of this complex state of mind, sometimes using Electroencephalographic (EEG) patterns. In layman terms EEG patterns are measurements done on the brain signals and analysis is done based on certain types of waves characterized into -
alpha,
beta,
gamma and
delta waves. Each of the waves corresponds to a certain kind of activity. For some interesting reading and detailed introduction to this study check out the ever reliable
WikipediaWhats surprising to me is that during our sleep, it has been observed that, we enter into a certain stage described as the
true delta sleep - the deepest sleep, the EEG graphs sometimes show a near "flat line", which is reported by numerous people as having a near-death experience. Our religious books sometimes refer to phrases like "
... in your sleep we take away your souls and return them back ..." (apparantly talking about the life-after-death phenomenon). Do both of these phenomenon mean the same? Your guess is as good as mine.
Sleep is a treasure to human beings, which cannot be achieved all the time. If you wish to sleep, the harder you try and concentrate on going to sleep the more horrible it will be and impossible it becomes. Problems related to sleeping and its associated remedies is a big study on its own. There is some
interesting research on sleep analysis being done at University of Zurich and here is a
good paper which describes a study on sleep using EEG analysis.
