How does night bring advice?

The expression “sleep on it” is based on the idea that sleep plays a crucial role in thinking, decision-making and problem-solving.

It’s not just a popular belief: science has shown that sleep has a direct impact on our ability to process information and clarify our thoughts.

Here’s an overview of how the night can bring advice:

By improving information processing

During sleep, particularly the REM phase, the brain sorts, organizes and consolidates the day’s information and memories.

This makes it easier to understand complex problems or find creative solutions, as the brain establishes connections between ideas or experiences that previously seemed disconnected.

• Reference: Walker, M. P., & Stickgold, R. (2010). Overnight alchemy: Sleep-dependent memory evolution. Nature Reviews Neuroscience, 11(3), 218-230.

Clarifying thoughts by taking a step back

When faced with a decision or problem, we often tend to focus on it intensely, which can cloud our judgment.

Sleeping allows us to “put distance” between ourselves and the problem, which helps us to see things more clearly when we wake up.

• Reference: Payne, J. D., & Kensinger, E. A. (2010). Sleep’s role in the consolidation of emotional episodic memories. Current Directions in Psychological Science, 19(5), 290-295.

Reducing the impact of stress and emotions

Fatigue or strong emotions (stress, anxiety) can impair our ability to think rationally.

A good night’s sleep helps calm these emotions, allowing us to make more thoughtful decisions.

• Reference: Goldstein, A. N., & Walker, M. P. (2014). The role of sleep in emotional brain function. Annual Review of Clinical Psychology, 10, 679-708.

Boosting creativity and intuition

Sleep encourages creative thinking. Studies have shown that innovative or unexpected solutions often emerge after a night’s sleep, as the brain explores different thought paths during rest.

• Reference: Cai, D. J., Mednick, S. A., Harrison, E. M., Kanady, J. C., & Mednick, S. C. (2009). REM, not incubation, improves creativity by priming associative networks. Proceedings of the National Academy of Sciences, 106(25), 10130-10134.

Through cognitive regeneration

Sleep allows the brain to “recharge”. After a day of thinking and making decisions, the brain needs rest to regain its full capacity to analyze and decide.

Researchers estimate that we make around 35,000 conscious and unconscious decisions a day, resulting in decision fatigue that night-time can help combat.

• Reference: Baumeister, R. F., & Tierney, J. (2011). Willpower: Rediscovering the greatest human strength. Penguin Press.

To find out more…

Night is the best time to take advice, because sleep gives the brain time to process information, calm emotions and regenerate its cognitive capacities. If you’re hesitating about a decision, and time allows, it can be useful to “sleep on it” to see things more clearly the next day.