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 intriguing¹ things we’ve learnt in recent years about our mind’s journey to the Land of Nod.

睡眠科学有时模糊而令人迷惑。研究人员至今仍不清楚大脑的极限、做梦的原因以及梦的含义。不过近年来，关于梦境之旅，我们发现了一些有趣的现象。

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:

下列10条来自过去的BBC未来频道和其它来源的惊人事实让我们多少了解为什么需要在晚上舒服的睡一觉。

1. Familiar smells can help to form memories in your sleeping brain, improving your performance at simple learning tasks.

1、相似的气味能帮助处于睡眠状态的大脑形成记忆，提高简单学习的效率。

2. The body shudders² people report as you fall asleep are surprisingly common, and harmless – they’re called hypnic jerks.

2、人们反映，睡着时抽搐出奇地普遍，而且无害。这叫入睡抽动。

3. One small study proposed that learning the didgeridoo aids sleep, perhaps because it strengthens breathing muscles.

3、一个小型研究表明学习澳洲土著乐器迪吉里杜管有助睡眠，也许是因为这会增强呼吸肌。

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.

4、根据昼夜节律，最自然的午睡时间是下午2点到4点之间。虽然晚点午睡更能精神焕发，但早点午睡更有助于提升创造力。

5. As we discovered earlier this week, a mutation³ in a gene called DEC2 might allow some people to sleep consistently for only four hours a night with no adverse⁴ physical effects….

5、本周早些时候我们发现，一种名为DEC2的基因变异使人每晚只睡4小时而没有副作用。

6. …however, that’s probably not you. Less than 5% of people are natural short sleepers⁵. Most people need eight hours, but around 30% of us get fewer than six per night.

6、但是，那可能不是你。不到5%的人是天生的短睡眠者。大部分人需要睡8个小时，但约30%的人每天只睡6小时不到。

7. One theory for why we need sleep is that our brains use the opportunity to consolidate⁶ memories from that day. We might also deal with the memory of unpleasant or traumatic events during sleep.

7、关于为什么人类需要睡眠的一个理论是，我们的大脑利用这个机会整合一天的记忆。我们可能还会在睡眠期间处理不愉快的记忆或内心创伤。

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.

8、一些研究人员用大脑活动来重建之前看过的YouTube视频。这被认为将来可以用与之相似的科技重现梦境。

9. Military researchers have found that if you save up sleep in advance by having early nights, sleep deprivation⁷ won’t hit you as hard.

9、军方研究人员发现，如果通过早点睡来补觉，睡眠不足就不会那么影响你。

10. If you go 12 consecutive⁸ nights on six hours’ sleep, it’s equivalent to a blood alcohol of 0.1%, which is marked by slurred⁹ speech, poor balance, and impaired¹⁰ memory. In other words, you’re drunk.

10、如果你连续12个晚上都只睡6小时，这相当于血液中的酒精含量达到0.1%，表现为口齿不清、平衡不好以及记忆受损。换句话说，你喝醉了。