Learning is hard enough when we’re conscious. It would be nice if we could close our eyes and leave the heavy lifting to our sleeping brains.
In the past, learning in your sleep might have been laughed off as a crazy fantasy sold by charlatans and science fiction films.
In the 1920’s, A. B. Saliger invented a Psycho-phone, an “automatic suggestion machine” that promised to give you “health” or “inspiration” if you played phonograph records at night, according to the Washington Post. Although thousands bought into the idea, Saliger’s business went under, perhaps because his Psych-phones weren’t delivering on its promise.
A new study found that those Psycho-phones were onto something: learning in your sleep is possible. We can’t learn skills or facts from sleep alone, but we can learn new memories, researchers found. A team of neuroscientists published a study in Nature Communications that outlines how they figured out how to teach participants acoustic lessons in their sleep.
The neuroscientists recruited 20 participants with no history of sleep disorders to listen to random acoustic noises while they slept. When participants woke up, they were asked to recall the pattern in the split-second white-noise sounds in the recordings. Those who listened to the clips during their light sleep cycles were able to do this at a rate that’s higher than random chance.
It’s a task that goes beyond passive learning, the scientists said.
“The noise samples are fully novel to listeners, ensuring the formation of new memories and not consolidation,” the study states.
Memories can be introduced and strengthened in our sleep
Memories can be strengthened or worsened, depending on when you introduce new stimuli into your sleep cycle. Participants weren’t able to recall the patterns as well during the deeper non-REM sleep sequences as they could during their lighter sleep stage.
Noise “presented during non-REM sleep led to worse performance as if there were a negative form of learning,” the study said.
This study reinforces previous sleep studies that found we can alter our mind while we sleep through reconditioning. A 2015 study found that being exposed to foreign language words in your sleep helps you identify and translate them when you wake up.
One study even got smokers to cut down on smoking through smell conditioning in their sleep. It turns out, if you’re forced to smell unpleasant rotting foods after being exposed to cigarette smoke in your sleep, you’ll want to smoke less when you’re awake.
So you can’t yet dream your way into learning a new language overnight. And if you put a book under your pillow, you’re still not going to have the contents inside absorbed into your brain by morning.
You can, however, teach yourself new memories and break old patterns by snoozing, according to sleep studies. Hey, it’s a start.