It may seem to you like time sleeping is time lost. To our brains, though, sleep is not only productive, but vital. Sleeping provides the chance for our brains to do some chemical house cleaning, which helps us feel rested, awake, and a lot less grumpy the next day.
And now, new research from the Ecole Normale Supérieure in Paris suggests that our brains are capable of both learning and suppressing information during different phases of sleep. Their work was publishedAug. 8 in the journal Nature Communications.
Researchers led by Thomas Andrillon, a psychologist studying sleep, hooked up 20 participants to electroencephalograms, which measure the brain’s electrical activity. In the lab before the individuals fell asleep, researches played them white noise, similar to television static. They interspersed this noise with blips of other sounds, and asked participants to pick out when they heard distinct patterns.
Participants were then allowed to get some shuteye through the night while wearing their electroencephalograms (granted, it probably wasn’t the best sleep of their lives). Researchers tracked their phases of sleep by measuring the different patterns of electrical activity the subjects’ brains produced, all while playing them some of the same sound patterns.
The next morning, researchers played participants the white noise interspersed with blips of other sounds again. All of them were better at picking out the patterns played during rapid eye movement, or REM sleep, than they had been the night before. They didn’t remember patterns that were played during non-REM sleep (the light and dreamless sleep that occurs before REM), as well.