Since 2004, scientific research has shown that a full night of sleep may lend itself to a burst of insight in the morning.
But what about the earlier stages of sleep?
That was the question posed by a group of researchers at the University of Hamburg, the Max Planck Institute for Human Development and the Max Planck UCL Centre for Computational Psychiatry and Ageing Research.
The research team found that even a 20-minute nap could deliver a "eureka" moment, and published their findings in the journal PLOS Biology this week.
For the study, 90 participants tracked a group of dots and decided whether the dots were generally moving towards one of the four corners of the screen.
There was a secret trick that made the task super easy: The correct response was paired with a color. Without knowing that trick in advance, however, the task was quite difficult.
Could a nap help?
To figure that out, in the middle of the task, the researchers let the participants take a 20 minute break — with the lights off, seated upon the most comfortable Ikea chair that cognitive neuroscientist Anika Löwe could find.
"We also told people to sleep 30% less the night before and not consume any caffeine for coming in at 1 p.m," Löwe told NPR.
During the experiment, participants' brain activity was measured with an electrode cap. Some stayed awake; some fell asleep.
Upon returning to the task after the break, those who napped figured out the color trick at a higher frequency than those who did not sleep. Even better: Those who managed to enter the first phase of deep sleep, known as the N2 phase. A startling 86% of those deep sleepers had a eureka moment — more than any other group.
Célia Lacaux, a cognitive neuroscientist at the University Geneva, who was not a part of this study, was really impressed by these results.
"I am super happy to see that they also replicated the fact that short nap is helpful for boosting insights," she said.
Lacaux and Löwe both say the next step is further research to determine why this is happening — at the level of biochemical level.
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This episode was produced by Megan Lim and Rachel Carlson. It was edited by Rebecca Ramirez and Patrick Jarenwattananon. Tyler Jones checked the facts. Jay Czys, Ko Takasugi-Czernowin and Tiffany Vera Castro were the audio engineers.
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