How to harness the power of sleep’s ‘twilight zone’

Creative napping
The inventor Thomas Edison slept for only four hours each night, but he caught up in the daytime with regular short naps. Edison had much the same idea as Salvador Dalí. While napping, he held a ball in each hand. The sound of them dropping snapped him back to consciousness.

He was viewed as slightly eccentric in the 19th century, but sleep scientists now think Edison may have had it right. Daytime naps, usually lasting no longer than an hour, allow us to find solutions to problems that would elude us in our waking hours.

It’s all explained by the electrical activity inside our brain, says Professor Espie. While busy at work, your brain is mostly producing fast, low-amplitude electrical waves. These beta waves are handy for moments of intense activity, or if you’re engaged in conversation, but they tend to crowd out other creative processes.

Then we get home and rest on our sofa. Our brain begins to produce slower, higher amplitude alpha waves, associated with relaxation. We begin to drift off; slowly, we approach sleep. Our alpha waves dial down, replaced instead with theta waves, often associated with daydreaming or being in a state of mental autopilot. And after that, we produce delta waves, associated with deep sleep.

All of these brain waves are necessary for a fully nourished mind, explains Professor Espie. As our brain makes each transition, it gains the ability to approach a problem in a new way – to look at a situation from another angle. It might be difficult to think of a solution to a problem while busy at work, when beta waves are dominating your brain. But a theta wave could do a better job. The mere process of falling asleep can, quite literally, give us a brainwave.

Your brain goes through the same process as you drift for your eight-hour night-time sleep, of course, but you are more likely to remember those creative thoughts after a short afternoon nap. No wonder Einstein, Napoleon and Da Vinci were such fans.

Scent
Scientists are also interested in the creative powers of scent, which has long been thought to carry profound links into our brain and memories. Have you ever walked into a kitchen, smelt a meal cooking on the stove and thought of a happy memory, often from years ago? That’s because of the extraordinary power of smell.

In 2011, in a study published in the Journal of Sleep Research, scientists at Harvard Business School showed how certain scents could spark creative activity in our brains. About 50 volunteers were invited one evening to a laboratory in the Netherlands. They were shown a video and asked to solve a problem. As they watched it, a vanilla scent was wafted into the room. Then they were told to get a good night’s sleep. Before drifting off, one group had the same vanilla scent sprayed into their bedroom. Another group was given a different smell (a “control odour”); the third group had no smell.

The next morning, immediately after waking, they were asked questions about the film. The group who slept with a vanilla smell scored considerably better. Scientists concluded that smelling vanilla during the night had sparked their brain into action – even though the participants were asleep, totally unaware of what was happening.

Recording thoughts
It’s all very well having brainwaves in bed – but what if you can’t remember them in the morning? The bizarre, abstract nature of sleepy thoughts mean they can be difficult to recall when our brain is in a state of alert wakefulness.

David Watson, a psychologist at the University of Notre Dame, Indiana, tracked 200 subjects over three months and found that those who scored lower on the creativity scale had a much harder time recalling their dreams, and thus probably found it more difficult to recall the creative thoughts they had while lying awake in bed. Partly it’s because they were simply having less interesting dreams, but also because they were failing to record them.

He recommends keeping a journal on your bedside table, so if you wake up in the middle of the night, you can quickly scribble any interesting thoughts. Some keen dream enthusiasts have a dictaphone on all night; if they wake, they can simply say what they’re thinking aloud, then listen back to it the next day.

It will probably sound like nonsensical gibberish – but it just might hold a creative gem.

The Telegraph, London

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