The science of sleep can be fuzzy and confusing at times. Researchers are still not sure what our brains are up to, why we dream, or what those dreams even mean. But there are some intriguing things we’ ve learnt in recent years about our mind’s journey to the Land of Nod.
Here are 10 surprising facts from the BBC Future archive and elsewhere that shed some light on why we need a restful night’s sleep:
1. Familiar smells can help to form memories in your sleeping brain, improving your performance at simple learning tasks.
2. The body shudders people report as you fall asleep are surprisingly common, and harmless – they’re called hypnic jerks.
3. One small study proposed that learning the didgeridoo aids sleep, perhaps because it strengthens breathing muscles.
4. The most natural time to nap, based on our circadian rhythms, is between 2 and 4pm. But while napping later in the day is more restorative, getting some shuteye earlier on is more likely to boost your creativity.
5. As we discovered earlier this week, a mutation in a gene called DEC2 might allow some people to sleep consistently for only four hours a night with no adverse physical effects….
6. …however, that’s probably not you. Less than 5% of people are natural short sleepers. Most people need eight hours, but around 30% of us get fewer than six per night.
7. One theory for why we need sleep is that our brains use the opportunity to consolidate memories from that day. We might also deal with the memory of unpleasant or traumatic events during sleep.
8. Some researchers have used people’s brain activity to reconstruct YouTube videos they were watching. It’s thought a similar technique could one day be used to recreate our dreams.
9. Military researchers have found that if you save up sleep in advance by having early nights, sleep deprivation won’t hit you as hard.
10. If you go 12 consecutive nights on six hours’ sleep, it’s equivalent to a blood alcohol of 0.1%, which is marked by slurred speech, poor balance, and impaired memory. In other words, you’re drunk.