You’ve almost certainly heard of “shower thoughts,” those random ideas of incredible brilliance, profundity, and/or weirdness that seem to invariably hit us in the middle of a shower. There’s a decent chance you’ve had one or two yourself. But have you ever wondered why?
To understand why shower thoughts happen, you need to know what your brain does when it’s out of the shower. It’s constantly thinking about something, scanning your environment, controlling your body, acting and reacting to whatever task you have at hand. It takes a lot of energy to do all this, which is why the brain uses up 20 percent of the calories we eat and oxygen we breathe, while only taking up two percent of our body’s real estate.
For virtually the entirety of the day, our brains are focused on the tasks at hand: cooking a meal, doing our jobs, getting the kids ready for school, etc. When we’re in the shower, however, we lose focus, because what’s to focus on? You’ve taken thousands of showers, so many that you barely need to be aware of what you’re doing. You can’t bring your smartphone in there to check Twitter. You’re (almost) always alone and left undisturbed. You know where the shampoo is, you know the places on your body that need extra attention. You’re on autopilot, which means your brain has much less to do.
To put it in scientific terms, the prefrontal cortex of your brain — the part that does the majority of your conscious thinking — relaxes, so it feels like you’re not thinking at all. In reality, of course, the rest of your brain is still hard at work: This is called the “default mode network,” which a team of scientists led by radiologist Marcus E. Raichle discovered in 2001, after discovering that people still had large spikes of brain activity even when they were resting or not focused on tasks. Even when you’re zoned out, a huge portion of your subconscious is still going hard, thinking about all the things you were thinking about before you zoned out, and a lot more.
What’s cool is, studies show that the parts of the brain that operate our default mode network are a lot more creative than our prefrontal cortexes. When we’re hyper-focused on a problem, our brains eventually get stuck in a rut because we fixate on it. The default network isn’t constrained in the same way, so it starts tackling the problem in all sorts of ways to find a solution. It’s much more powerful than our prefrontal cortex, too — it uses 90 percent of the blood and energy the brain receives.
However, there’s another reason why these eureka moments tend to hit us in the shower: Showers feel good! They release a chemical neurotransmitter called dopamine in our brains, which not only makes us feel good, scientists have also found it can also bolster creativity.
Basically, showers are the perfect place for your brain to do its best thinking. So the next time you have a problem you just can’t solve, stop dwelling on it and hit the shower instead.