Thomas Edison tapped into the creative imagination more than 100 years ago. He found that taking a quick snooze boosted his creativity, and a new study finds the famous inventor may have been on to something! He would hold a ball in his hands while napping and when his muscles relaxed, the ball fell from his hands, hit the floor and woke him just in time to capture sleep-inspired ideas.

Researchers at the Paris Brain Institute found taking a quick nap taps into a ‘creative sweet spot’ because the brain only drifts into the first stage of sleep, known as the hypnagogia state, or N1, considered the transitional state between being awake and sleep. During this stage, our muscles start to relax and we have dreamlike visions about recent experiences. N1 is also known as hypnagogic hallucinations. It’s also the least studied stage of sleep. When we sleep, we only spend usually less than 10 minutes in N1.

It’s characterised by involuntary and imagined experiences, and it is during N1 that your muscles relax and you begin to have visions of recent events which help you through a mental block to solve a puzzle, a test, or finish a project. The study set out to see if these visions can help people overcome mental obstacles and used the same method as Edison. They were each given an empty plastic bottle to hold in their right hand, while researchers recorded their brain activity with electro-encephalography helmets to measure electrical waves produced by neural cells.

103 volunteers were recruited for the study and asked to work on a maths test. However, the volunteers were not told about a hidden rule designed to easily solve the puzzle. The researchers gave each participants 30 tries at the test and those who failed to find the hidden rule took a quick 20-minute nap.

The researchers found those who spent at least 15 seconds in N1 had an 83% chance of solving mathematical puzzles, while those who remained awake had only a 30% chance.