ABSTRACT
Sleep occupies one-third of our lives and significantly influences the other two-thirds. Sleep is not just the absence of wakefulness but rather an essential life process with its own distinct physiology. Descriptions of sleep can be found through the ages. The Upanishads, an ancient Indian philosophy text (circa 1000 B.C.), considered that dreaming and deep dreamless sleep comprised two of the four states of being (1). Sleep phenomena are described in many Western works as well (2). Greek mythology includes Hypnos, the god of sleep, and the hero Endymion, who after a kiss from the moon sleeps forever and remains eternally youthful. In Shakespeare’s Macbeth, Lady Macbeth suffers from nightmares and sleepwalking after helping Macbeth kill the king of Scotland. Charles Dickens’ Pickwick Papers described the sleepy fat boy Joe, who likely had obesity-hypoventilation syndrome, a disorder associated with obstructive sleep apnea.
