Ulysse Sabbagh

Walking away from a problem to do simple, routine tasks, and letting the mind wander in the process, can spark creative new connections or approaches to solving dilemmas, says a 2012 study in Psychological Science. That helps explain why “a lot of great ideas occur at transition times,” when people are waking up or falling asleep, bathing, showering or jogging, says Jennifer Wiley, a psychology professor at University of Illinois at Chicago and lead author of a 2012 research summary in Current Directions in Psychological Science.

A nice WSJ article exploring some of the most recent research to find the origin of the ah-ha moment. If you can’t access it, there are some tidbits on Quartz.