How Sleep Helps the Brain
Sleeping is essential for health, we know. But how many know the processes that clear out the clutter for the next day’s work?
A new study published in Science says that while you sleep, neurons clear out metabolites from the brain. This is a critical function for maintaining homeostasis (dynamic stability), the paper says, because it removes “potentially neurotoxic waste products that accumulate in the awake central nervous system.” Some of those toxins could be implicated in serious brain disorders, like Alzheimer’s Disease. In a sense, the brain cleans itself while you sleep. Emily Underwood at Science Now calls sleep “the ultimate brainwasher.”
Live Science adds that sleep gives the body time to repair itself and stabilize memories formed during the day. Using a pithy analogy based on the research findings, Charles Choi writes,
“The brain only has limited energy at its disposal, and it appears that it must [choose] between two different functional states — awake and aware, or asleep and cleaning up,” Nedergaard said in a statement. “You can think of it like having a house party. You can either entertain the guests, or clean up the house, but you can’t really do both at the same time.“
Underwood couldn’t make evolutionary sense of the need for sleep.
Every night since humans first evolved, we have made what might be considered a baffling, dangerous mistake. Despite the once-prevalent threat of being eaten by predators, and the loss of valuable time for gathering food, accumulating wealth, or having sex, we go to sleep. Scientists have long speculated and argued about why we devote roughly a third of our lives to sleep, but with little concrete data to support any particular theory. Now, new evidence has refreshed a long-held hypothesis: During sleep, the brain cleans itself.
That still doesn’t make evolutionary sense, though, if a predator were to eat the hunter while he takes time out for brain-washing. Wouldn’t survival of the fittest demand that predators attack when it’s easiest? The author of Psalm 104 had a different outlook: one of a harmonious creation, each part performing its function in the cycle of day and night:
20 You make darkness, and it is night,
when all the beasts of the forest creep about.
21 The young lions roar for their prey,
seeking their food from God.
22 When the sun rises, they steal away
and lie down in their dens.
23 Man goes out to his work
and to his labor until the evening.
24 O Lord, how manifold are your works!
In wisdom have you made them all;
the earth is full of your creatures.
Sleep is not a mistake. Too much sleep, though, can be a moral lapse, as shown by the many times Solomon warns of the “sluggard” in his book of Proverbs. Actually, another discovery announced in Nature reinforces the good old work ethic. In “How exercise boosts the brain,” the short article states, “A protein molecule secreted by muscles during exercise boosts the expression of factors that help to protect brain neurons.” That molecule is called irisin – as in “I risin’ up to get some exercise!” Exercise increases this protein in the brain. “When levels of irisin or its progenitor were raised experimentally in the blood and in neurons, genes associated with learning and memory became active in the brain.”
In summary, sleep to let the toxins get cleaned out, then rise, work hard, and let irisin improve your cognitive function. Here’s another helpful tip: stand while you work, if you can. Too much sitting defeats the benefits of exercise, an article on the BBC News said. But by standing more often, you can lose calories and increase triglycerides. Over a year, that could amount to losing 8 pounds of fat. Some offices are providing their workers with stand-up computer desks. Some are even offering slow-motion treadmills that allow them to walk as they type. Give it a try; with all the other healthy habits you are building into your life, this one allows you to improve your health while getting your work done. If you can’t stand while working, at least get up and move around often. The body was made for action and rest.
Everything for a purpose. Sleep well! Work hard. Take a stand. Do something worthwhile with these amazing gifts from your Creator.