The ABCs of Catching Zs—
Normal Sleep, What It Is
From Rest to Slumber
"Honey, go to sleep now," says the Mommy. "Why do I have to?!" the child demands and, with that response, asks a questions that goes far beyond the dynamics of a familiar moment in the bedtime struggle. Why do we "have to" go to sleep? What is this mysterious one-third of our lives we call sleep, and what are its normal patterns? How do these change over an individual's lifetime? What do we know about the range of healthy variation in sleep patterns as a person grows and ages? And, of course, "why?" Why do we sleep at all ... what possible functions does sleep serve?
To attempt to answer these questions (questions which, incidentally, represent only the tip of the iceberg of inquiries that might be made about sleep), we must first be in possession of a consistently valid and reliable definition of the phenomenon of "sleep." The fact that we so suddenly are carried off in the arms of Morpheus once we fall into sleep, may suggest a galvanic process in which a switch is thrown, suddenly carrying us into new territories, neurologically and psychologically speaking. Once we can define what sleep is, then, perhaps, we will be able to more clearly delineate and describe some of these qualities.