Understanding the Language of Silence - Sleep, Sleep Behavior and Sleep Disorders. Dr. Amrit Lal
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insomniacs in the solitude of the night when rest of the country sleeps. They may find some solace and perhaps a way to come out of this problem. However, it is not the cook who decides the taste of the stew, but the actual diners who judge its taste. I can only add that sleep, unlike many other aspects of life, is a lifelong call for everyone. For most people sleep improves with a correct approach – be it based on pharmacology or on sleep hygiene. However, this is not to deny that many other may continue to sleep less than what is optimum for a healthy living.
Finally and with apology I have to express my limitation that panning through the ages I cannot pretend personal knowledge on more than a few frames of time and topics discussed. You will find me heavily dependent on the work of others. But it would be distracting to acknowledge all such debts one after another in the thickets of foot notes in a small volume like this. I convey my collective “Thank You” to all upon whose work I have freely and gratefully drawn.
AUTHOR
INTRODUCTION
Science of sleep is fascinating. Sleep is not an option or a volitional activity; it is the very essence of one’s existence - or an area of relevance because all of us sleep. Research has generated enough insight into the functions of this somnolent state that consumes one–third of our lives that some “gurus” of new business management philosophy abhor as waste – a third of life of inactivity and un-productivity in the bed! It is too much for them to swallow, “for there will be enough sleeping in the grave.”
Sleep in is not actually a waste of time since it has a great recuperative potential for productivity – both mental and physical. During daytime work an individual uses up a lot of hormones which keep him/her in good health. These hormones are replenished by the endocrine system when we snooze. Among these, somatotropin (also called growth hormone) is also released during sleep, which helps in the reconstructive task of repairing worn out cells and those cells destroyed during the waking hours. . Release of growth hormone is related, in part, to repair processes that occur during sleep. At the same time certain chemicals in the body, among them peptides, are produced, which not only have sleep-inducing effects but are also known to bolster human immune system by increasing the production of anti-bodies. They also help us fight infections. Other hormone such as thyroid-stimulating hormone is also released prior to sleep. Thyroid hormone makes way for harmonious growth of human body.
Sleep is not an inert psychosomatic state. Although there is a modest decrease in metabolic rate and some other vital functions of the human body, there is no evidence that any major regulatory system of the body, including the brain, shuts down in sleep. On the contrary, brain buzzes with neural activity and endocrine system involved in secretions of certain hormones (such as growth hormone and prolactin and sleep-inducing melatonin) actually increases. Slumber scientists, in particular, have identified and recorded electrical impulses in brain during sleep through electrocephalograms (EEGs) as brain waves which are classified according to their frequencies; electrooculogram (EOG) which measures eyes rate in the eye socket, and, electromyogram (EMG) which measures electrical activity associated with muscles. These measurements, EEGs, EOGs and EMGs, are simultaneously recorded to allow relationships among them to be compared and inferences drawn.
Through the ages, world’s greatest thinkers from Greek philosopher, Aristotle, to Austrian neurologist and founder of psycho-analyst Sigmund Freud, have provided diverse explanations on man’s sleep behavior from their respective perspectives. Sleep was once considered “an irreversible stupefaction – the absence of overt objective behavior which a working individual is capable of.” It has also been romanticized as “death of each day’s life.” But this concept of sleep as a passive state of periodic torpor, during which overt behavior and consciousness remains suspended has been replaced by a new approach – the study of sleep not simply as an absence of wakefulness but a dynamic mode of existence during which the brain buzzes with frenzied activity and many physiological functions are hyper-active.
A lot actually goes on during sleep. Even though slumber scientists are still not very certain about many aspects of sleep but they know that the brain performs critical memory consolidation and other important functions during the night for which it uses sleep as a workdesk to perform much needed maintenance job in the body.
We talk about “good” sleep, “poor” sleep, “light” sleep and “deep” sleep. Sleep behavior is characterized by three salient features, namely, reversibility, recurrence and spontaneity. There is no such thing as “sleeping like a log of wood.” This shows a great heterogeneity in the qualitative aspects of sleep architecture which is as important as total sleep time. Despite spending one-third of our lives asleep, sleep continues to be a complex and mystifying – like the smile of sphinx!
This presentation treats sleep not as a passive state of quiescence but as an active phase of life with inroads into psycho-social and neurological aspects of sleep and pathology of sleep disorder. Under normal circumstances, people in good health (physical, mental and social) tend to sleep well; whereas those in ill health suffer from many sleep maladies. Even a minimal loss of sleep can have deleterious impact on a person’s mind, energy and ability to handle day-to-day demands of modernity. It saps the quality of life that may lead to systemic diseases.
How much sleep we need varies between individuals but generally changes as we age. But it is a myth that sleep disorders affect only adults and the elderly. According to American Academy of Pediatrics sleep disorders affect 20 to 45 percent of children and adolescents, impacting their daily functioning, ability to concentrate and causing irritation and generating a propensity for irritability. When it comes to the elderly, because of their peculiar genesis and ramifications, sleep disorders in this group of population deserve a specific mention. The elderly not sleeping well, fragmented sleep marked by frequent arousals and repeated rounds of bath room for urination throughout the night and, finally, waking up in the early hours of the morning is quite a phenomenon and particularly exhausting. These are manifold geriatric problems. Also, the fact which has a significant impact on physiology and psychology of aging as well as sociology of old age has to be reckoned in any discussion of sleep disorders in the elderly, because the incidence of sleep disorders rise with age and changes in life events. In a National Institute of Aging study of 9,000 persons aged 65 and above, over half of the men and women reported at least one chronic sleep disorder. (Sleep, 1995; 18). The elderly not only require sufficient total sleep time but sleep that is in harmony with the individual’s circadian rhythm (daylight and darkness at night) because problems with proper sleep regulation in the elderly typically include difficulties in falling asleep, less time spent in sleep and early morning awakenings. As such evaluation of their problems is a multi-dimensional task which includes careful screening for sleep hygiene and other factors that may be contributing to particular sleep disorders.
And today we get 90 minutes less sleep every 24 hours than people got a century ago, mostly because of altering patterns of work where 24-hour shifts make nights look like day through specially designed lighting to induce workers to remain awake at night. Nature crafted nights for rest and relaxation and days for work and activity, but now the demands of modernity have put this pyramid upside down. Today, with more than a third of world population on night shifts, and money markets across various time zones conducting multi-billion dollars transactions around the clock and with tough deadlines imposed on enterprise by global competition, a man’s sleep debt keeps on accumulating. Much of this sleep deprivation is voluntarily as it is considered a mark of success to work long hours – a macho attitude! On this scenario, a 2012 study Center for Disease Control and Prevention, Atlanta, estimated that almost one-third of working adults in America get only six hours or less of sleep at night.
Man basically is the most self-deprived mammalian species on this planet. Reasons for this deprivation are as varied as the manifestations of this development – ranging from work culture round the clock to access to technology and ever shifting work schedules.
Less sleep than what the body needs can cause in serious consequences. Several major disasters have been linked in part with too little sleep in the work place - Nuclear melt-downs at three-mile Island in Pennsylvania, Chernobyl in Russia and the Exxon Valdez in Alaska are in part attributed to sleep deprivations of the workers on the job.
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