We all sleep: infants and children more than adolescents, adolescents more than adults, and some adults more than others. But a periodic alternation of sleep with wakefulness is universal, and suggests that sleep fulfils a basic biological need of the organism. On average, human beings spend one third of their lives in sleep.
What happens in sleep is that our consciousness withdraws from the field of its waking experience; it is supposed to be resting, suspended or in abeyance, but that is a superficial view of the matter. What is in abeyance is the waking activities, what is at rest is the surface mind and the normal conscious action of the bodily part of us; but the inner consciousness is not suspended, it enters into new inner activities, only a part of which, a part happening or recorded in something of us that is near to the surface, we remember. There is maintained in sleep, thus near the surface, an obscure subconscious element which is a receptacle or passage for our dream experiences, and itself also a dream-builder. After a time this subconscious activity appears to sink back into complete inconscience we speak of this state as deep dreamless sleep; thence we emerge again into the dream-shallows or return to the waking surface.
But in fact, in what we call dreamless sleep, we go into a profounder and denser layer of the subconscient, a state too involved, too immersed or too obscure, dull and heavy to bring to the surface its structures, and we are dreaming there but unable to grasp or retain these more obscure dream figures. However, it is possible to become wholly conscious in sleep; it is found that then we are aware of ourselves passing from state after state of consciousness to a brief period of luminous and peaceful dreamless rest, which is the true restorer of the energies of the waking nature, and then returning by the same way to the waking consciousness.
The Nature of Sleep: the Scientific Viewpoint
In order to try to understand sleep, scientists use an apparatus known as an electroencephalogram (EEG). In sleep experiments, electrodes attached to a sleeper's head are connected to this machine which then records brain wave patterns. Devices are also attached to the sleeper to record eye movements, heart rate, temperature, and so forth. From thousands of laboratory experiments over the years, scientists have concluded that there are two principal kinds of sleep, and that a person normally moves from one to another at 90-minute intervals throughout the night.
When we first go to bed, we fall into slow-wave sleep, so named for the fact that brain waves slow down. We gradually drift into a quiet state in which both temperature and pulse rate drop. Subjects awakened from this stage of sleep seldom report dreams. Then, approximately 90 minutes after falling asleep, the blood pressure, pulse and breathing become irregular. The ears are tuned for hearing and the eyes dart back and forth. This is REM (for rapid eye movement) sleep, also known as paradoxical sleep because it is unlike the popular idea of sleep as a quiet state. The brain is as active as when awake, and the brainwaves resemble those emitted in the daytime. Subjects awakened from paradoxical or REM sleep almost always report dreams. About 25 percent of the night is spent in this kind of sleep.
Another interesting — and paradoxical — observation about REM sleep is that although the brain and body appear to be as highly aroused and active as during the waking state, subjects awakened from this stage report that they were very deeply asleep. And the sleeper is also much less aware of external stimuli during REM sleep. Scientists interpret this finding as follows. When we are attentive to something, we are less likely to be distracted by any noise or movement around us than might otherwise be the case. The child reading with avid interest may not hear his mother calling. In other words, insensitivity to external stimulation is not always indicative of mental lethargy; to the contrary, it may reflect a high degree of attentiveness.
Narcolepsy, Insomnia and Sleep Deprivation
Pity the poor narcoleptic. He is likely to fall asleep at the peak moment of a film, in the midst of a conversation, while driving a car. He suffers from narcolepsy, a disorder in which the victim is subject to
sudden, uncontrollable attacks of sleep lasting anywhere from five to twenty minutes. Narcoleptics may have other symptoms, too. They sometimes lose muscle tone suddenly and fall down, and in the few moments between waking and sleeping, they may hallucinate or experience brief paralysis. The cause of narcolepsy is not understood by conventional science, though world literature has several vivid victims of this disorder, from Kumbhakarna, the giant brother of Ravana in the Ramayana, to Rip Van Winkle.
While the narcoleptic cannot stay awake, the insomniac cannot fall asleep. Among the commonest reasons for insomnia are anxiety and depression. Physical ailments can also make it difficult to sleep as can abuse of common drugs that affect the brain. Over the long run, sleeping pills, especially barbiturates, are apt to make insomnia worse rather than better. There are no pills that foster normal sleep. Some pills abolish the deepest stages of REM sleep, and most suppress much-needed REM sleep.
Then there are those who simply do not need to sleep as much as most people. Napoleon and Winston Churchill are famous examples. Churchill always insisted on an afternoon "siesta" of about one hour, but then would work until two or even three in the morning, only to rise again by six a.m. ready for more intensive work.
Perhaps no one has described the anguish of the insomniac as vividly and poetically as Shakespeare's King Henry V
O Sleep, O gentle Sleep,
Nature's soft nurse, how have I frightened thee
That thou no more wilt weigh my eyelids down
And steep my senses in forgetfulness?
Why rather. Sleep, liest thou in smoky cribs,
Upon uneasy pallets stretching thee
And hush'd with buzzing night-flies to thy slumber,
Than in the perfumed chambers of the great
Under the canopies of costly state,
And lull'd with sound of sweetest melody?
O thou dull god, why liest thou with the vile
In loathsome beds, and leavest the kingly couch
A watch-case of a common 'larum bell?
Wilt thou upon the high and giddy mast
Seal up the ship-boy's eyes, and rock his brains
In cradle of the rude imperious surge
And in the visitation of the winds,
Who take the ruffian billows by the top,
Curling their monstrous heads and hanging them
With deafening clamour in the slippery clouds,
That, with the hurly, death itself awakes?
Canst thou, O partial Sleep, give thy repose
To the wet sea-boy in an hour so rude,
And in the calmest and most stillest night,
With all appliances and means to boot,
Deny it to a king? Then happy low, lie down!
Uneasy lies the head that wears a crown.
(King Henry IV, 2, III, i.4-31.)
Insomnia is not considered an illness, and most insomniacs are able to live normal lives. However, the effects of prolonged sleep deprivation are well known: a loss of efficiency in mental and physical functioning, irritability, and tendencies toward perceptual distortions and ideational confusion. When laboratory animals have been deprived of sleep, they die after ten sleepless days.
The American aviator Charles Lindbergh describes a remarkable experience brought on by sleep deprivation during his record-breaking flight across the Atlantic:
"On May 20, 1927, after months of concentrated effort, frustration, and the threat of probable failure, I flew from New York to Paris in a single-cockpit, single-engine mono plane christened Spirit of St. Louis. I had spent twenty three hours without sleep when I took off, and obviously there would be no opportunity to sleep before I landed. My lack of sleep turned out to be the most-difficult and dangerous factor of the flight, but it resulted in an inner experience that seemed to penetrate beyond mortality.
"There comes a point when the body's demand for sleep is harder to endure than any other pain I have encountered, when it results in a state of semiconsciousness in which an
awareness exists that is less acute but apparently more universal than that of the normal mind. Before my flight was halfway finished, I found that I could not force myself to stay awake through will power. The rational mind I had previously known and relied upon had less and less effect on my body's responses. There were lengthening periods when it even lost the knowledge of its own existence, when an intelligence without the need for reason had replaced it. "Over and over again on the second day of my flight, I would return to mental alertness sufficiently to realize that I had been flying while I was neither asleep nor awake. My eyes had been open. I had responded to my instruments' indications and held generally to compass course, but I had lost sense of circumstance and time. During immeasurable periods, I seemed to extend outside my plane and body, independent of worldly values, appreciative of beauty, form, and colour without depending upon my eyes. It was an experience in which both the intellectual and sensate were replaced by what might be termed a matterless awareness. It was the only occasion in my life when I saw and con versed with ghosts.
"They appeared suddenly in the tail of the fuselage while I was flying through fog. I saw them clearly although my eyes were staring straight ahead. Transparent, mistlike, with semihuman form, they moved in and out through the fabric walls at will. One or two of them would come for ward to converse with me and then rejoin the group behind. I can still see those phantoms clearly in memory, but after I landed at Paris I could not remember a single word they said."
The following words of The Mother are very instructive:
"To sleep well one must learn how to sleep. If one is physically tired, it is better not to go to sleep immediately, otherwise one falls into the inconscient. If one is very tired, one must stretch out on the bed, relax, loosen all the nerves one after another until one becomes like a rumpled cloth in
one's bed, as though one had neither bones nor muscles. When one has done that, the same thing must be done in the mind. Relax, do not concentrate on any idea or try to solve a problem or ruminate on impressions, sensations or emotions you had during the day. All that must be allowed to drop off quietly; one gives oneself up, one is indeed like a rag. When you have succeeded in doing this, there is always a little flame there — that flame never goes out and you become conscious of it when you have managed this relaxation. And all of a sudden this little flame rises slowly into an aspiration for the divine life, the truth, the consciousness of the Divine, the union with the inner being, it goes higher and higher, it rises, rises, like that, very gently. Then everything gathers there, and if at that moment you fall asleep, you have the best sleep you could possibly have. If you do this carefully, you are sure to sleep, and also sure that instead of falling into a dark hole, you will sleep in light, and when you get up in the morning, you will be fresh, fit, content, happy and full of energy for the day."