You know the feeling. Under the rush of the shower's water, you're mindlessly lathering up and then—boom!—you're hit with a stroke of brilliance. A thought comes into your head, seemingly out of nowhere. Perhaps it's a solution to a nagging work problem. Maybe it's the inspiration to start something completely new. Those eureka moments aren't unleashed from your soap's bubbles. But being in the shower apparently does, in fact, create the perfect conditions for coaxing out your inner genius.

Research has long shown that you're more likely to have a creative epiphany when you're doing something monotonous. Since routine activities like cleaning your apartment, lifting weights or showering don't require much thought, you flip to autopilot. This frees up your unconscious and relaxes the prefrontal cortex—the brain's command center for decisions, goals and behavior—allowing you to make new connections that your conscious mind would've dismissed. Which is why shower thoughts are so different from the ones you make in your 9-5 life, when your focus is tighter and you rely more on analytical thinking.

In the shower, those eureka thoughts come via insight rather than analytical thinking. And new research published in Scientific American help explain why all the pieces of a puzzle appear to fall into place with little conscious effort. John Kounios, a psychologist at Drexel University and one of the study's co-authors put it this way:

"Because such processing occurs largely outside a person's awareness, it is all or nothing—a fully formed answer either comes to mind or it doesn't. This hypothesis is supported by EEG and functional MRI scans, which revealed in previous studies that just before insight takes place, the occipital cortex, which is responsible for visual processing, momentarily shuts down, or 'blinks,' so that ideas can 'bubble into consciousness.' As a result, insights are less likely to be incorrect. Analytical thinking, in contrast, happens consciously and is therefore more subject to rushing and lapses in reasoning."

The time of day plays a role in your genius ideas too. Most of us shower in the morning or the evening, when we're most tired. And that's when we're most creative as well, according to the journal Thinking and Reasoning. That foggy state of mind temporarily weakens your brain's censors, letting in all those floating thoughts on the periphery which make great ideas possible. In other words, you've got the perfect storm for the perfect idea. So pull the shower curtain, turn on the water and just wait for the brilliance to wash over you.