Sleep is a function of the brain. However, the ultimate physiological function of sleep remains enigmatic and unknown despite recent extensive research of this ubiquitous and important brain activity. Sleep intervenes in functions of somatic growth, regeneration, and memory. Sleep is important in medicine because it modulates quality of life, while its disorders provoke family pathology, disturb work routines, alter social activities, and, in general, affect the health of the individual (1).