In 1965,17-year-old high school student, Randy Gardner stayed awake for 264 hours.
1965年，17岁的高中生兰迪·加德纳264小时没有睡觉。
That's 11 days to see how he'd cope without sleep.
累计11天，来看看他是怎么应对不睡觉的。
On the second day, his eyes stopped focusing.
第二天，他的目光停止对焦。
Next, he lost the ability to identify objects by touch.
接下来，他失去了通过触摸来识别物体的能力。
By day three, Gardner was moody and uncoordinated.
到第三天，加德纳喜怒无常，变得不协调。
At the end of the experiment, he was struggling to concentrate,
在实验结束时，他奋力集中，
had trouble with short-term memory, became paranoid, and started hallucinating.
但短期记忆了出现问题，变得偏执，并且开始出现幻觉。
Although Gardner recovered without long-term psychological or physical damage,
虽然加德纳恢复了，并没有长期的心理或物理伤害，
for others, losing shuteye can result in hormonal imbalance, illness, and, in extreme cases, death.
但对有些人来说，失去睡眠可能会导致荷尔蒙失调、疾病，并且在极端情况下死亡。
We're only beginning to understand why we sleep to begin with, but we do know it's essential.
我们才刚刚开始理解为什么我们要睡觉，但我们知道这是必不可少的。
Adults need seven to eight hours of sleep a night, and adolescents need about ten.
成年人需要一个晚上七八个小时的睡眠，青少年需要大约十个小时。
We grow sleepy due to signals from our body telling our brain we are tired, and signals from the environment telling us it's dark outside.
我们犯困是由于我们的身体信号告诉我们的大脑我们累了，环境就是告诉我们天黑了的信号。
The rise in sleep-inducing chemicals, like adenosine and melatonin,
催眠化学品的兴起，像腺苷和褪黑激素，
send us into a light doze that grows deeper, making our breathing and heart rate slow down and our muscles relax.
把我们从打盹变成深眠，使我们的呼吸和心脏速率减慢，让我们的肌肉放松。
This non-REM sleep is when DNA is repaired and our bodies replenish themselves for the day ahead.
此非REM睡眠时是DNA提前一天修复我们的身体、补充自己的时候。
In the United States, it's estimated that 30% of adults and 66% of adolescents are regularly sleep-deprived.
在美国，据估计，30%的成人，66%的青少年经常睡眠不足。
This isn't just a minor inconvenience. Staying awake can cause serious bodily harm.
这不仅是一个小小的麻烦。保持清醒会导致严重的人身伤害。

When we lose sleep, learning, memory, mood, and reaction time are affected.
当我们失眠时，学习、记忆、心情和反应时间都受到影响。
Sleeplessness may also cause inflammation, hallucinations, high blood pressure, and it's even been linked to diabetes and obesity.
失眠也可引起炎症、幻觉、高血压，它甚至被认为与糖尿病和肥胖症有关。
In 2014, a devoted soccer fan died after staying awake for 48 hours to watch the World Cup.
2014年，一个忠实的足球迷在48小时不睡觉观看世界杯后死亡。
While his untimely death was due to a stroke,
虽然他的英年早逝是由于中风，
studies show that chronically sleeping fewer than six hours a night
研究表明，长期每晚睡眠少于六小时的人
increases stroke risk by four and half times compared to those getting a consistent seven to eight hours of shuteye.
中风风险是那些每晚睡七至八小时的4.5倍。
For a handful of people on the planet who carry a rare inherited genetic mutation, sleeplessness is a daily reality.
对在这个星球上携带着一种罕见基因突变的人类来说，失眠是一种日常现实。
This condition, known as Fatal Familial Insomnia, places the body in a nightmarish state of wakefulness,
这种情况被称为致死性家族失眠症，身体在清醒的一个噩梦般的状态，
forbidding it from entering the sanctuary of sleep.
禁止它进入睡眠的避难所。
Within months or years, this progressively worsening condition leads to dementia and death.
在几个月或几年，这种逐步恶化的状况导致痴呆和死亡。
How can sleep deprivation cause such immense suffering?
睡眠剥夺为何引起如此巨大的痛苦？
Scientists think the answer lies with the accumulation of waste products in the brain.
科学家认为，答案在于大脑中废物的积累。
During our waking hours, our cells are busy using up our day's energy sources,
在我们醒着的时候，我们的细胞都在忙着用我们一天的能源，
which get broken down into various byproducts, including adenosine.
其中细分为各种副产品，包括腺苷。
As adenosine builds up, it increases the urge to sleep, also known as sleep pressure.
随着腺苷的积聚，它增加了冲动睡觉，也被称为睡眠压力。
In fact, caffeine works by blocking adenosine's receptor pathways.
事实上，咖啡因通过阻断腺苷的受体途径来起作用。
Other waste products also build up in the brain, and if they're not cleared away,
其他废物也在脑中积聚，如果他们不清理掉
they collectively overload the brain and are thought to lead to the many negative symptoms of sleep deprivation.
就会共同使大脑超载，这被认为是导致睡眠剥夺的诸多不良症状的原因。
So, what's happening in our brain when we sleep to prevent this?
那么，当我们睡觉时，我们的大脑是怎样阻止这种情况的呢？
Scientists found something called the lymphatic system,
科学家们发现了淋巴系统，
a clean-up mechanism that removes this buildup and is much more active when we're asleep.
一种能消除这种堆积，并且当我们睡着时更加活跃的机制。
It works by using cerebrospinal fluid to flush away toxic byproducts that accumulate between cells.
它的工作原理是利用脑脊液冲走在细胞之间的有毒物质。
Lymphatic vessels, which serve as pathways for immune cells, have recently been discovered in the brain,
淋巴管，为免疫细胞提供路径的血管，最近被发现存在于大脑中，
and they may also play a role in clearing out the brain's daily waste products.
他们也可能在清除大脑日常代谢物中扮演了重要的角色。
While scientists continue exploring the restorative mechanisms behind sleep,
虽然科学家还在继续探索关于睡眠的恢复机制，
we can be sure that slipping into slumber is a necessity if we want to maintain our health and our sanity.
我们可以肯定的是，如果我们要保持我们的健康和理智，打瞌睡是必需的。