Have you ever wondered why your best ideas come to you in the shower?
You're not imagining it. It's what's known as "the shower effect".
Research led by Zachary Irving, an assistant professor at the University of Virginia, noted that people often seem to generate some of their best creative ideas during activities such as showering or walking.
Across two studies in 2022, Dr Irving and his team found "mind wandering leads to more creative ideas, but only during moderately engaging activities".
But what is it about these everyday activities that apparently unlocks our creativity?
How 'divergent thinking' boosts our creativity
Alan Pegna is an associate professor of psychology at the University of Queensland who specialises in cognitive neuroscience and works as a clinical neuropsychologist.
Dr Pegan says our brains have different modes of thinking that can impact our creativity.
Convergent thinking is the decision-making process that results in choosing the most logical or correct solution to a problem.
Divergent thinking is the creative process that involves coming up with multiple ideas that may follow many lines of thought and tend to generate new and original solutions to problems.
Divergent thinking is the sort that leads to our brilliant shower thoughts, Dr Pegna says.
It can boost creativity by helping us think outside the box — for example, by "connecting things together that [we] might not immediately think of".
"When you are in a situation, such as having a shower or going for a walk in the forest, you essentially stop being focused on a goal … [and] your mind starts to wander," Dr Pegna says.
"It's this positive, constructive aspect of mind wandering — of positive daydreaming, if you like — that brings up ideas, and then suddenly associating things randomly and coming up with stuff that you haven't thought of before."
Why it's important to think outside the box
From a young age, the way we are taught to learn is centred around rote learning, a memorisation technique based on repetition that involves convergent thinking.
Dr Pegna notes that in recent years, there has also been some focus on trying to help students develop their ability to think divergently.
"But, all in all, schoolwork is about focusing on something and learning the answers," he says.
This goal-oriented manner of thinking often translates into our adult working lives.
"Most people are in situations where they have to focus and think in this convergent way," he says.
"We have a job, we have expertise, we know what we have to do.
"There's not enough space to apply this divergent mode of thinking; there's not enough space for mind wandering.
"[Yet that mind wandering] is related to creativity, and ideas that are developing in one's mind actually incubate during these periods of divergent thinking.
"So, we should have more space to do that."
The benefits of a wandering mind
Dr Pegna says we should nurture our abilities to think outside the square. That could mean ruminating over a tricky problem in the shower, or letting your mind roam free during a walk in nature.
"What's happening when you're walking through the forest is your mind literally wanders. It's racing around and picking up on different things — mixing up ideas," he says.
"It has positive effects, and it helps in problem-solving."
When it comes to the concept of mind wandering, Dr Pegna says people often immediately think about what are perceived as "negative aspects", such as ADHD, children who are unable to focus on their schoolwork, recurrent anxious thoughts and pessimistic self-examination.
Dr Pegna says that in some of the clinical work he undertakes, he encounters "lots of people who are worried about having attentional difficulties" because they have trouble focusing on their work.
"Even though it's a fact that some people have a strong inability to focus their attention, it's … not completely true that it's an impairment," he says.
"I think it's an important thing for humans to be able to divert to mind wandering. There are aspects of it that are very healthy."
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