Sleep is a precious commodity here in Geezerville. At a certain age, in fact, we begin to pursue it with the sort of evolutionary fervor we once reserved primarily for procreative activities. And yet, for many elderly Americans, a good night’s sleep remains a maddeningly elusive goal. As Jane Brody notes in a recent New York Times column, a 1995 study found that 28 percent of people over 65 had difficulty falling asleep and 42 percent said they had trouble falling asleep and staying asleep. Given our current propensity to while away our evening hours staring at various electronic screens, Brody suggests those numbers are probably even higher now.
I am not one of these cranky insomniacs. Most evenings, I’m conked out within a few minutes of my 11 o’clock bedtime; most mornings, I rise reasonably refreshed, around 8. My Lovely Wife, on the other hand, is a night owl who will not entertain the notion of slumber until she is completely convinced she’s exhausted enough — physically and, more importantly, mentally — to hit the pillow and stay there.
She’s been this way since our first child was born, nearly 29 years ago. Hyperalert to any disturbances from the crib down the hall, and secure in the knowledge that I’ve been known to sleep through minor earthquakes, she took on the responsibility and maintains it now, long after our offspring have exited the nest.
I’d worry about MLW if she wasn’t able to snooze happily into the mid-morning hours when necessary. (She’s self-employed and has few time-sensitive obligations.) But for those aging insomniacs who never catch enough z’s, there can be serious consequences: cognitive disorders, psychomotor retardation, immune system dysfunction, and depression, among others.
Scientists, physicians, and psychiatrists have been trying to figure out the mysteries of sleep for as long as people have been tossing and turning. There are plenty of suggested cures — avoiding caffeine, alcohol, and computer screens before bedtime; ramping up your exercise; eschewing midday naps; and the like — but there’s little consensus on what might be happening in the body to make us more or less likely to snooze. Or why we need to sleep at all.
Researchers at Harvard Medical School recently weighed in on the debate with a study suggesting that it’s all connected to the body’s immune response, specifically certain type of brain-based immune proteins known as inflammasome NLRP3. When the brain detects an infection or inflammation in the body, it releases sleep-inducing immune molecules.
“We already know that sleep plays a protective role in resolving infections so our observation of inflammasome activation following infection suggests this immune mechanism may have a brain-protective role,” says lead study author Mark Zielinski, PhD.
I’m no sleep expert, but this would lead me to believe that my nightly snoozefest is the happy result of some stubborn infection, which seems to be something of a mixed blessing. Eradicate the infection, douse the inflammation, and the reward is an endless string of sleepless nights?
No one really questions that there is a restorative function to sleep, but University of Wisconsin–Madison scientists argue that its primary purpose is to help us forget. In a recent study published in the journal Science, biologists Giulio Tononi, MD, PhD, and Chiara Cirelli, MD, PhD, report that the brain’s synapses grow so exuberantly during the day that the circuits get too noisy. When we sleep, our brains surreptitiously delete unnecessary memories so we aren’t overloaded with useless information, rendering our useful memories fuzzy.
When I mentioned this the other day to MLW, she wondered how the brain could determine the difference between necessary and unnecessary memories. I said I didn’t know and I wasn’t going to lose any sleep over it. But now I’m sorry I mentioned it all, because she probably will.