In art, literature, or science, it’s an elusive question: how do you create something new? How do you get past a block or solve a seemingly impossible problem? Well, putting it aside and sleeping on it just might help.
“Sleeping on it” has led to many famous inventions and artistic creations. An example is the German chemist, Friedrich August Kekulé. As legend has it, after dozing in front of a fireplace he awoke with a sudden insight. He quickly sketched his idea: a string of atoms that joined at both ends to form a ring. This drawing later became the basis for his discovery of benzene.
Kekulé’s experience is backed up by numerous studies which show that having a snooze can promote creative problem-solving. But now scientists are starting to uncover why sleep may make you more creative. Dr. Penelope Lewis at Cardiff University suggests that it is the combination of non-REM (NREM) and REM sleep that allows the brain to detect commonalities between what may appear to be dissimilar concepts and present us with the keys to solving whatever problem is on our minds.
As you begin to nod off, your brain enters into four stages of sleep: the first three are NREM, and the final one is REM sleep. During NREM, or slow wave sleep, your brain replays memories. New information is initially channeled to the hippocampus, a small region located deep within the brain that is shaped like a seahorse. Importantly, the hippocampus organizes and prioritizes the incoming information.
“You’re forming brand new memories all the time, but you don’t necessarily retain the details of everything you’ve ever experienced,” says Lewis. “Non-REM sleep is important for forming generalities.” The sleeping brain gleans knowledge from our daily life, holds onto what is essential and discards the rest. This is how it creates an understanding of the world around us.
For example, you might replay memories of moving into a new home. All of them involve unfamiliar rooms, boxes, furniture, and maybe movers and a truck or car. This is the brain’s way of forming not just an isolated memory of a single event in your life. Instead it is building a representation of what “moving day” means — the gist of it.
Lewis claims that that during NREM sleep two key areas of the brain — the hippocampus and the neocortex — are actually working closely together. The hippocampus may even influence the neocortex by grouping together apparently divergent concepts and prompting the search for any overlapping areas between them. The result is that ideas are more likely to be related.
“You can detect similarities between different concepts which you might not have put together at all before,” says Lewis. Other bits of information are also activated by the haphazard activation of neurons. So, if you’re stuck on a problem when you drift off, after waking you just might have the answer.
More than half a century ago, Eugene Aserinsky and Nathaniel Kleitman discovered REM sleep, upending the science of sleep. Before the 1950s scientists had devoted their attention entirely to NREM sleep. Yet after detecting rapid eye movement, scientists knew that REM was more than just another stage of NREM sleep.
In adults, REM sleep is a short phase that makes up only about 20 percent of the total amount of time spent in slumber. Babies spend about half their time in REM sleep. This may be because they are constantly inundated with new information and are learning so much every day.