Sleep, consciousness and human behaviour

    30-Aug-2020
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Zaurez Hamid
We commonly associate reality with consciousness. This is our psychological condition when we are awake. It is the state of awareness created by the input of information from our eyes, ears and other senses into the brain’s cerebral cortex. The cortex continuously analyses all that input. We rely on its analysis for our sense of reality. So, is dreaming in sleep a reality? Let us first understand what sleep is.Sleep is viewed as an instinctive expression of innate behaviour elicited by “inducing” stimuli.Sleep is a basic human need.So basic that we sleep about one-third of our lifetime satisfying this need, but unlike other basic need, sleep is something we usually do not think about we are deprived of sleep. It’s only then that we discover, that we are deprived as have how big a difference a little sleep loss makes in our lives.
The irony is that much as we need sleep, no one can explain why we need even it, not even the world-renowned sleep experts. Through scientific observations, it has been found that there are some exciting discoveries related to sleep. It is observed that however, we may experience it sleep is not a single psychological state; it is a complex cycle of several stages a cycle we repeat several times each night. EEG scientist can record the electrical signal activity of the brain. The EEG is their principal tool for identifying the stages of the sleep cycle. No one knows what happens when we fall asleep. The EEG tells us that when we close our eyes, our brains gradually switch from a regular activity rhythm to the slower-paced alpha rhythm. Our muscles relax, our general activity slows down, and finally, we cross the threshold what we call falling asleep.
When we fall asleep, during the first 15 minutes of sleep, our general brain activity slowdown continues; scientists call this period - stage 1 sleep. Then after 15, more minutes the EEG begins to record a slower rhythm, we become even more relaxed. This is stage 2 sleep, and it lasts about another 15 minutes. Then the EEG picks up the first signs of an even slower rhythm the Delta wave; it signals the onset of stage 3 sleep finally in another 15 minutes delta waves predominate our brain activity. In this stage, our muscles are deeply relaxed; our pulse and breathing are prolonged. We shift to stage 4 sleep, the deepest sleep of all about one hour after we first fall asleep, but the sleep cycle is not complete. The final stage is most remarkable, and we experience REM (Rapid Eye Movements). REMS are only one of the curious things we do after stage 4 of sleep. The EEG suddenly shows alpha waves and other evidence of brain activity at the border of sleep and waking. This stage is known as Paradoxical Sleep. Paradoxical because our brainwave pattern looks more like waking than sleeping. We humans, often make a definite distinction between our conscious experiences and our unconscious experiences we have.
When we’re not awake, that means that a dream is an unconscious experience. However, surprisingly research into the sleep cycle indicates that sleeping dreaming and waking consciousness maybe not so separate states; instead, they are probably varieties of a single cycle-logical and physical process. One that creates both - Our waking reality and the altered reality of our dreams. Why do we sleep? What does sleep do for us, if anything? Furthermore, why do we dream? These fundamental questions remain tantalizing mysteries, to date!
Writer is an Alumni of IIT, Jodhpur.