The BBC reports, Sleep 'cleans' the brain of toxins
"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," said researcher Dr Maiken Nedergaard.
"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."Over at The Atlantic, Jessica Lehay writes:
I’ve been reading about daydreaming extensively lately, and it has caused me regret every time I roused one of my students out of their reverie so they would start working on something “more productive.” Daydreaming has been found to be anything but counter-productive. It may just be the hidden wellspring of creativity and learning in the guise of idleness.
Not all mental downtime is alike, of course. Downtime spent playing a video game or zoning out with a television show may have its charms, but the kind of downtime I am talking about is different. I’m talking about the kind of mind-wandering that happens when the brain is free of interruption and allowed to unhook from the runaway train of the worries of the day. When the mind wanders freely between random thoughts and memories that float through our consciousness, unbidden. Television, videogames, and other electronic distractions prevent this kind of mental wandering because they interrupt the flow of thoughts and memories that cement the foundation of positive, productive daydreaming.Yawn. Sigh. Zzzzzzzzzzzzz.