Commentary: Could ‘sleeping on it’ really help you make better decisions?

DREAMING YOUR WAY TO CREATIVITY

Thomas Edison, who helped invent the light bulb, often used daytime naps to help spur his creativity even though he claimed not to sleep more than four hours a night.

When Edison went for his daytime naps, he fell asleep with a ball in his hand. As he fell asleep, his hand relaxed, and the ball fell to the ground. The noise of the ball hitting the floor startled Edison awake. 

He, and other famous thinkers including Salvador Dali, claimed that it was that transitional state, the moment between wake and sleep, that fuelled their creativity.

In 2021, French scientists put Edison’s claim to the test. They had participants attempt to solve a maths problem. Unknown to the participants, the problem had a hidden rule that would allow them to solve the problem much faster.

After working on the problem, they had participants fall asleep like Edison did. Each participant held a cup in their hand that they would drop if they fell asleep.

After this delay, participants were re-tested on the maths problem. They found that those participants who drifted off into a light sleep were better able to discover the hidden rule, compared with participants who remained awake, or who entered into deeper stages of sleep while still holding the cup.

During this twilight period between wake and sleep, many of the participants reported hypnagogia, dream-like imagery that is common during sleep onset.

In 2023, a different set of researchers investigated whether the content of hypnagogia was at all related to the three creatives tasks centred on a tree theme that their participants performed right before going to sleep. For example, listing all the creative, alternative uses they could think of for a tree. 

They found that creative problem-solving was enhanced when the hypnagogic imagery involved trees, suggesting imagery helped them to solve the problem.

So it turns out that Edison was right, sleep onset really is a creative sweet spot, and sleeping on it works.

Dan Denis is a lecturer in psychology at the University of York, in the United Kingdom. This commentary first appeared on The Conversation.