熬夜真的让人变傻，科学家拍下人脑睡眠全程

Recently, Medical News Today reported on a study that found that specialized immune cells are more active in the brain during sleep, busy performing maintenance work.

最近《今日医学资讯》就一项研究进行了报道，研究发现睡觉时大脑中的特异性免疫细胞更活跃，在进行繁忙的维护工作。

Researchers know that sleep is important — not just in terms of allowing the brain to reactualize, but also for "making space" for "cleaning" processes to take place.

研究人员知道睡眠不仅对于大脑重新开始工作非常重要，而且有助于为“清理”过程“腾出空间”。

However, many of the mechanisms through which this clearing out of brain waste takes place during sleep remain unclear.

然而人类依然不清楚大脑在睡眠期间清理大脑垃圾的很多机制。

Now, researchers at Boston University in Massachusetts have found that during sleep, the fluid present in the brain and spinal chord — called the cerebrospinal fluid — washes in and out, like waves, helping the brain get rid of accumulated metabolic "trash."

现在马萨诸塞州波士顿大学的研究人员发现睡眠期间存在于大脑和脊髓中的脑脊液进进出出，就像波浪一样，帮助大脑清除堆积的代谢“垃圾”。

"We've known for a while that there are these electrical waves of activity in the neurons. But before now, we didn't realize that there are actually waves in the cerebrospinal fluid, too," study co-author Laura Lewis explains.

研究的合著者Laura Lewis解释道：“我们早就知道神经元里有这些活动电波，但此前我们并不知道脑脊液中也有波。”

The new study — the results of which appear in the journal Science — included 13 participants ages 23–33 who agreed to undergo brain scans while asleep.

这项新研究的结果发表在了《Science》期刊上，研究对象是13个23-33岁的人，他们同意在睡眠期间接受脑部扫描。

They saw that cerebrospinal fluid appears to "synchronize" with brainwaves, which likely helps remove brain waste. This waste includes potentially toxic proteins that may otherwise form buildups that can impair the flow of information between neurons.

他们看到脑脊液似乎与脑电波“同步”，可能有助于清理大脑垃圾，包括潜在的有毒蛋白质，它们可能会在神经元之间形成阻碍信息流动的结构。

These findings, the researchers add, could also shed fresh light on the underlying mechanisms in conditions such as Alzheimer's disease, in which toxic protein plaques play a key role in memory loss and other cognitive impairments.

研究人员补充说这些研究结果也揭示了阿尔茨海默症等疾病的潜在机制，主要是有毒蛋白斑块导致记忆丧失和其他认知障碍。

They also explain that normal aging may be associated with poorer self-cleaning in the brain. With age, human brains tend to generate fewer slow waves, which may reduce blood flow in the brain, as well as cerebrospinal fluid pulsations.

他们也解释说正常的老化可能与大脑自我清洁能力下降有关，人类大脑老化会产生更少的慢波，减少大脑中的血液流动和脑脊液脉动。

"It's such a dramatic effect," emphasizes Lewis. "[Cerebrospinal fluid pulsating in the brain during sleep] was something we didn't know happened at all, and now we can just glance at one brain region and immediately have a readout of the brain state someone's in."

Lewis强调说：“这真是惊人的结果，我们完全不知道‘睡眠期间大脑中有脑脊液脉动’，现在我们只需看一眼大脑的一个区域，立刻就能读取某人的大脑状态。”