- Few volunteers were asked to convert a string of numbers into a shorter sequence, following two simple rules
- What the volunteers weren’t told was that there was an easy trick: The second number in the sequence would always be the correct final number, too
- Once discovered, this cheat code dramatically cut the solving time
- After doing 60 of these trials on a computer, the volunteers earned a 20-minute break in a quiet, dark room
- Reclined and holding an equivalent of Edison’s “alarm clock,” participants were asked to close their eyes and rest or sleep if they desired
- People who had fallen into a shallow, early sleep were 2.7 times as likely to spot the hidden trick as people who didn’t fall asleep