A s a strategy for raising educational achievement, sleep should rank highly. Yet you will hear scant mention of sleep in the education discourse. For all the debate on curriculum and assessment, pedagogy and behavior management, so little attention is given to an issue that acutely affects our everyday lives.

Matthew Walker’s Why We Sleep addresses that dearth. Sleep, it appears, is vital to every aspect of our mental and physical wellbeing. Walker’s expertise lies in neuroscience, and his well researched work exposes the fallacy in thinking we can get by with compromising on our sleep — not just the amount of sleep we get, but also the consistency of our sleep patterns. After reading it, I was convinced that I have chronic sleep deprivation. Walker made me reflect on my morning coffee routine and my occasional nap. His book has been — that’s right — a wake-up call.

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.

Walker is only confirming what problem solvers have long understood. Thomas Edison is known to have turned power napping into a craft — he believed his deepest insights originated from the sweet spot between conscious and unconscious states. He would hold a bunch of ball-bearings as he power napped, so that just as he drifted into deep slumber, they would drop and clatter onto the floor — awaking him at the opportune moment.

French polymath Henri Poincare articulated the importance of sleep in the nature of invention, stating, “The role of this unconscious work in mathematical invention appears to me incontestable.” Jacques Hadamard agreed with his compatriot, making note of how he alternated between conscious and unconscious thought when working on mathematics.

“Sleep on it” would pass as folk wisdom, except that it heralds from some of the most creative thinkers of past and recent times and is now reinforced by neuroscience.

Responding to Hadamard, Albert Einstein spoke of the “combinatory play” that is “the essential feature in productive thought,” concluding: It seems to me that what you call full consciousness is a limit case which can never be fully accomplished.” No wonder that George Polya, in his classic How to Solve It, advised maths students to “take counsel of your pillow” when caught in the web of a problem.

Bringing the discussion to the present day, mathematician Andrew Wiles devotes one of the Bs of his “3B” mantra to Bed (along with Bus and Bath), in homage to the importance of switching off to allow creative insights to make their way in.

Sleep on it would pass as folk wisdom, except that it heralds from some of the most creative thinkers of past and recent times and is now reinforced by neuroscience. The link between deliberate sleep patterns and core tenets of mathematical thinking, such as problem solving and creativity, is inescapable.

So why has education not embraced sleep as a central part of its design?

Acknowledging the importance of sleep would meant that the education system would have to adapt to the varied sleeping patterns of students. The most important concept I took away from Walker’s book is circadian rhythm, or the body clock.

Our bodies are attuned to rising and sleeping at different hours, depending on our state of biological development. Adolescents have a much more difficult time waking in the early morning, compared to children and young adults, because their body clock dictates that they should be sleeping. It’s not that adolescents are lazy; their tendency to drift off in mid-morning classes is partly a consequence of being denied their natural sleeping routine. For education to meet the needs of its students, timetables would have to change — later starts and finishes for high-schoolers would fit better with their inherent sleeping rhythms. But adaptive timetabling does not fit our standardized model of education.

Sleep does not lend itself to the measurement paradigms of today’s education system, either. The education system is hell-bent on measuring whatever it can, and then assigning importance only to what has been measured. It should be evident that the nature of problem solving — so much of which is rooted in unconscious thought — is holistic and beyond the blunt tools of written assessment.

Any timed exam that seeks to capture students’ problem solving skills within a fixed period (looking at you, PISA) is, by the findings of neuroscience, a contradiction in terms. Embracing sleep means letting go of futile efforts to measure every nuance of students’ thinking. If education is to truly become evidence-based, it cannot, in good conscience (or should that be good unconscience?) afford to ignore emerging insights from neuroscience.

The importance of sleep is by now irrefutable — the onus is on education policy, practice, and research to adapt. And if you’re still in doubt of the power of the unconscious, I can only advise you to read Walker’s book and, well, sleep on it.