科學家發現睡覺時腦脊液清理大腦垃圾的活動

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《今日醫學新聞》就一項研究進行了報道，研究發現睡覺時大腦中的特異性免疫細胞更活躍，在進行繁忙的維護工作。

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.
研究人員知道睡眠不僅對於大腦重新開始工作非常重要，而且有助於爲“清理”過程“騰出空間”。

However, many of the mechanisms through which this clearing out of brain waste takes place during sleep remain unclear.
然而人類依然不清楚大腦在睡眠期間清理大腦垃圾的很多機制。

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."
現在馬薩諸塞州波士頓大學的研究人員發現睡眠期間存在於大腦和脊髓中的腦脊液進進出出，就像波浪一樣，幫助大腦清除堆積的代謝“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解釋道：“我們早就知道神經元裏有這些活動電波，但此前我們並不知道腦脊液中也有波。”

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.
這項新研究的結果發表在了《Science》期刊上，研究對象是13個23-33歲的人，他們同意在睡眠期間接受腦部掃描。

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.
他們看到腦脊液似乎與腦電波“同步”，可能有助於清理大腦垃圾，包括潛在的有毒蛋白質，它們可能會在神經元之間形成阻礙信息流動的結構。

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.
研究人員補充說這些研究結果也揭示了阿爾茨海默症等疾病的潛在機制，主要是有毒蛋白斑塊導致記憶喪失和其他認知障礙。

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.
他們也解釋說正常的老化可能與大腦自我清潔能力下降有關，人類大腦老化會產生更少的慢波，減少大腦中的血液流動和腦脊液脈動。

"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強調說：“這真是驚人的結果，我們完全不知道‘睡眠期間大腦中有腦脊液脈動’，現在我們只需看一眼大腦的一個區域，立刻就能讀取某人的大腦狀態。”