The Lacaux team also experimented with various objects that the participants should hold during a nap: spoons, steel bulbs, stress balls, etc. It turned out that Edison was right, and a cup was by far the best choice. It also turned out that most participants acknowledged that there was a hidden rule after the falling cup woke them up. The nap was short, only long enough to enter the light, non-brake N1 sleep phase.
Initially, the Schuck team wanted to replicate the results of the Lacaux study. They even bought exactly making cups, but the cups failed this time. “It just didn't work for us. People who fell asleep often did not drop these cups – I don't know why,” says Schuck.
The bigger surprise, however, was that the N1 phase -sleep did not work either.
The dots
The Schuck team set up an experiment in which 90 participants were asked to follow dots on a screen in a series of tests, with a nap between 20 minutes in between. The dots were quite small, colored purple or orange, placed in a circle, and they moved in one of the two directions. The task for the participants was to determine the direction that moved the points. This can vary from simple to really difficult, depending on the amount of jitter that the team has introduced.
The insight that the participants could discover was hidden in the color coding. After a few tests in which the direction of the dots was random, the team introduced a change that tied the movement to the color: orange dots always moved in one direction and the purple dots moved in the other. It was up to the participants to sort this out, either awake, either awake or through a nap-induced insight.
