THE SCIENCE OF SLEEP
Sleep is a biological need of man. It is essential for the smooth running of life. Like hunger and thirst, it too comes at fixed cyclic intervals. It energizes the body and freshens the mind. Lapsing into sound sleep is an art; it is not something haphazard. Those who are skilled in this art are able to put it to optimum advantage.
Ayurveda gives very deep analysis of sleep. It classifies sleep into six kinds: (i) sleep generated by physical exhaustion, (ii) caused by mental fatigue, (iii) post-ailment sleep, (iv) sleep induced by some bodily hurt, (v) that brought about by increase in cough, and (vi) tamoguni sleep. This last kind fills the body and mind with ‘tamas’ or darkness instead of freshness and vigor. Death is known as the mahatamoguni sleep. The physical death of yogis, however, is called ‘divine sleep’.
Modern psychology divides sleep into three phase-types: light sleep, deep sleep and the dreaming phase. These phases come in succession. In the deep sleep state, a person becomes completely oblivious of his surroundings and remains totally unaffected by them. Scientists believe that it is this phase which is the real sleep time. It takes away all mental and physical tiredness and fills a person with energy and vitality.
In the third phase of dreaming, the conscious mind takes a back seat and the unconscious mind becomes active. It is this mind, which ‘sees’ dreams. The psychologists are still not able to fully grasp the mechanism and meaning of dreams. But the yogi understands this phenomenon in its totality. Through various yogic techniques he refines and purifies his unconscious mind to the extent where it becomes non-existent. The yogi acquires full control over sleep. He does not dream; rather he illumines this dream phase with the bright rainbow-like lights of a Deepawali.
An ordinary person requires sleep because his unconscious has a vast ocean-like expanse. But how much sleep is really needed? Psychologists opine that the required quantum of sleep varies from person to person. It depends on many factors – physical and psychological state of a person as well as on his social and material environs. A child who sleeps for 15 hours can hardly manage a sleep of even 4-5 hours in old age. The thumb rule is that only that much sleep is required as fulfills the requirements of the body and mind. Napoleon slept for only 3 hours while Einstein for 10. On an average, a person sleeps for 5 – 7 hours.
In this wonderful creation of God there are many creatures who do not sleep at all and yet remain healthy and happy, and are able to perform all their activities perfectly well. Ants do not sleep; nor do blackbucks, and antelopes. Horses take their nap in standing postures. There have been some humans too who did not sleep in their entire lives. There is a case of one particular lawyer who never slept right from his childhood to death. Contrariwise, there is a ‘Kumbhakarni sleep.’ Kumbhakaran, a character in the Ramayan, used to sleep for six months at a stretch. These are some of the puzzling aspects of sleep which yet remain unsolved.
The yogic concept is that sleep undergoes a transformation at the apex level of Samadhi. Here occurs the final resolution of sleep, which comes as a climax of the yogic progression. But where is its starting point? Which are the factors which hamper sleep, and which ones are helpful? Modern psychologists are making inroads into the hidden layers of sleep and have come out with interesting results. According to them excessive brooding is inimical to sleep, and so is negative thinking.
Lack of sleep is extremely injurious to mental and physical health. Statistics reveal that one sleepless night reduces work efficiency by the same extent as is caused by high level of alcohol in blood. Lack of sleep disturbs the rhythm of internal biological cycle and the body consequently is restricted to utilize only 60 – 75% of its capacity. One sleepless night can bring about a reduction of up to 30% in our thinking capacity. Inability to take a correct decision, irritability, uncontrolled anger, temporary lapses of memory – all these are some other ill-effects of insomnia.
Prolonged lack of sleep has a direct bearing on diseases like heart aliment, hypertension, diabetes etc. In extreme cases, even sudden cardiac arrest may occur. Lack of sleep means metabolic and hormonal imbalance. It results in obesity, acidity and even ulcers. The immune system is weakened, and the body falls prey to many kinds of viral and other infections. According to doctors, pain below the waist and headache are a result of insufficient sleep. It slows down the reaction to situations of depression, frustration and anxiety. Continued lack of sleep puts the nervous system in a high state of agitation. It hampers the functioning of neurotransmitters and thereby starts a cycle of multiple nervous and mental disorders with serious complications. Not only the lack but also the excess of sleep is harmful. Studies show that women who oversleep damage the functioning of their hearts. During sleep, the coronary veins shrink and its excess may invite cardiac arrest.
Researchers of the Harvard Medical School claim to have identified the precise link in the chemical chain that regulates the sleep cycle of the body. This is the T.G.F. Alpha chemical found in either side of the brain. The leader of this research team says that the sensors in hypothalamus catch signals from not only the brain but also retina of the eyes. This is because T.G.F. Alpha is formed in the retina too. Its implication is that the quantum of light that enters the eye, and its duration both affect the biological clock of the body. For this reason the sleeping-waking pattern keeps changing with the gradual change in seasons.
We can rid ourselves of the problem of insomnia by a proper understanding of the art of living. If the life style is orderly, food and diet is satwik, and thinking is positive there will not be any problem of sleep. What is more, with the help of various techniques of yoga sleep can even be mastered and harnessed into some extraordinary uses.
There were two brothers of the names of ‘Truth’ and ‘Falsehood’. Truth was handsome and clean while Falsehood was dirty and distasteful. So wherever the latter would go he would be unwelcome. Out of jealousy, he decided to take revenge on Truth.
Once both embarked on a pilgrimage. As usual people responded to them differently everywhere they went – Truth with respect; and Falsehood with disdain.
In course of their pilgrimage they reached Badrinath. Both entered a pond for bath. While Truth was engrossed in cleaning his body thoroughly, Falsehood slyly wore the clothes of Truth and ran away. When Truth came out of the pond, he had no choice but to put on the left-behind clothes of Falsehood. From that time onwards both are ever moving and meeting people. But now the situation is reversed. Falsehood is respected and honoured because he has the clean mask of Truth on him. Truth, on the other hand, is wandering from door to door fruitlessly, wearing the black mask of Falsehood.