When confronting a problem, or looking for creative inspiration, people get told “to sleep on it”. This turns out to be useful advice not just because it’s based on years of smart people saying that, but also because modern neuroscience research is proving it to be true. We can benefit a lot from sleeping more (on average people don’t get enough sleep) and dealing with complex issues is one more thing that sleep is good for.
Sleep, Walker suggests, is crucial to problem solving. When my students are stuck on a math problem, sleep on it is often the only wisdom I have to offer. This adage has served me well in the past and now, thanks to Walker’s research, it enjoys a strong neurological basis. Walker demonstrates that problem solving can seamlessly occur in the REM phase of sleep. It is in this critical stage of unconsciousness that we form novel connections between individual chunks of knowledge. In a REM sleep is where our ideas crystalize and recombine into new, creative thoughts. The link between sleep and inspiration is so pervasive that the phrase sleep on it exists in most languages.