For the past month, attempting to learn French has been a part of my nighttime routine.
After I turn on this 5-hour video, I dim my iPhone screen and doze off, the French man on the screen whispering avoir and être into my ears.
There are loads of sleep-learning playlists available, all with a seductive promise of effortless productivity. Listen to the app, go to sleep, and voila — wake up bilingual.
It seems too easy to be true, and research suggests that it probably is.
"People can't learn any new verbal information while they're asleep," says Anat Arzi, a neuroscientist who studies sleep-learning at the Weizmann Institute of Science, tells Tech Insider. "It's too complex for the brain."
If I were to learn any French, Arzi says it would happen in the 15 seconds between consciousness and when I fall asleep.
While it's nearly impossible to learn a new language this way, other research shows sleep can enhance our memory.
In a new study from Brown University, two groups of participants were shown images with different patterns of lines. One group was asked to recall the patterns after they took a 90-minute nap. The other group was asked to recall them without sleep.
The researchers found that those who took naps were able to remember the patterns more easily.
"Sleep reactivates certain cortexes of the brain," Masako Tamaki, one of the study's authors, tells Tech Insider. "The brain doesn't just take a break during sleep."
To learn a new language, we need a good night's sleep, since it helps the brain process information from the previous day. Arzi says we shouldn't disturb our sleep with noise.
"We want to reset our brains so that we can get back to our studies," she says.
For me, the nightly French lessons made it extremely hard to fall asleep. Some mornings, I didn't feel as refreshed. Most nights, I lost about 30 minutes of sleep to shut off my brain. A month later, the only French words I know are bonjour, au revoir, and croissant.
I did learn something though: I will sacrifice 24-hour productivity if that means more sleep.
