Why do we sleep, anyway? asked the subhead introducing the many stories. How much sleep do we need? And just what are dreams — to say nothing of nightmares — made of?
The various and varied articles that filled the entire section attempted to formulate answers based on some of the same new research that was cited in the articles I wrote about earlier. (In some cases, it was particularly close, as in Jane Brody's piece titled "At Every Age, Feeling the Effects of Too Little Sleep." Let's say that the same press releases may have been drawn upon in several instances.) Overall, the articles suggested, answers to these basic queries may not be all that forthcoming — and more questions may have arisen among these scientists during their research.
As reporter Benedict Carey wrote in his article, titled "An Active, Purposeful Machine That Comes Out at Night to Play," "scientists have been trying to determine why people need sleep for more than 100 years. They have not learned much more than what every new parent quickly finds out: sleep loss makes you more restless, more emotionally fragile, less able to concentrate and almost certainly more vulnerable to infection. They know, too, that some people get by on as few as three hours a night, even less, and that there are hearty souls who have stayed up for more than a week without significant health problems."
But now, Carey pointed out, there are scientists who are saying that a "vital function" of sleep has to do with learning and memory. According to this approach, "sleep plays a critical role in flagging and storing important memories, both intellectual and physical, and perhaps in seeing subtle connections that were invisible during waking — a new way to solve a math … problem, even an unseen pattern causing stress in a marriage."
The theory has stirred up controversy, of course, with competing scientists arguing that it's still not at all clear that the sleeping brain can do anything different from what the waking brain does with memories in quieter, contemplative moments.
Still, the article reported, this most cutting-edge research "underscores a vast transformation in the way scientists have come to understand the sleeping brain. Once seen as a blank screen, a metaphor for death, it has emerged as an active, purposeful machine, a secretive intelligence that comes out at night to play — and to work — during periods of dreaming and during the netherworld chasms known as deep sleep."