睡眠到底是如何洗去大腦中的毒素的呢

睡眠到底是如何洗去大腦中的毒素的呢

Every night when you sleep, the brain literally washes out toxins built up during the day - but no one's been sure how, until now.

每天晚上，當你睡覺的時候，大腦會洗掉白天產(chǎn)生的毒素——但是直到現(xiàn)在，沒有人知道是怎么做到的。

Scientists in the US have discovered a link between slow brain waves during deep sleep and a wave of fluid that washes through, clearing out the mess.

美國科學家發(fā)現(xiàn)，深度睡眠時緩慢的腦電波和一波經(jīng)過大腦的液體之間存在聯(lián)系。

The discovery could pave the way towards new ways to cure or prevent Alzheimer's disease.

這一發(fā)現(xiàn)可能為治療或預防阿爾茨海默病的新方法鋪平道路。

It's been known for a long time that sleep is really important for brain health, study author Laura Lewis told NPR, "but why it is was more mysterious."

研究報告的作者勞拉·劉易斯告訴美國國家公共廣播電臺(NPR)說:“長期以來，人們都知道睡眠對大腦健康真的很重要，但為什么會這樣呢?這個問題更神秘。”

Her team put people into MRI machines while they slept measuring their blood oxygen levels, while EEG caps measured the brain's electrical currents.

她的團隊讓人們在睡覺時測量血氧水平，同時讓他們接受核磁共振成像儀的檢測，而腦電圖儀則測量大腦的電流。

They found that during deep sleep, the brain's neurons would sync up - turning on and off at the same time. When they were off, the brain doesn't need as much oxygen, so blood flow reduced. In its place, cerebrospinal fluid would wash in.

他們發(fā)現(xiàn)，在深度睡眠時，大腦的神經(jīng)元會同步起來——同時開啟、同時關閉。當他們離開的時候，大腦不需要那么多氧氣，所以血液流動減少，取而代之的是腦脊液。

Before each wave of fluid, we would actually see a wave of electrical activity in the neurons, Lewis said. "This electrical wave always happens first, and the CSF wave always seems to follow seconds later."

“在每一波液體出現(xiàn)之前，我們實際上會在神經(jīng)元中看到一波電活動，”劉易斯說。“這種電波總是先出現(xiàn)，腦脊液似乎總是在幾秒鐘后出現(xiàn)。”

This only happens during deep sleep - not light slumbering or dreaming, and definitely not while people were awake. Previous studies have found a link between not getting enough deep sleep and memory problems.

這種情況只會發(fā)生在深度睡眠的時候，而不是在輕度睡眠或做夢的時候，也絕對不會發(fā)生在人們清醒的時候。之前的研究已經(jīng)發(fā)現(xiàn)深度睡眠不足和記憶問題之間存在聯(lián)系。

It's already known that people with Alzheimer's disease have less of these electrophysiological slow waves, so they have smaller and fewer slow waves, said Lewis.

劉易斯說:“我們已經(jīng)知道，老年癡呆癥患者的這種電生理慢波較少，所以他們的慢波更小、更少。”

Alzheimer's has been linked to the build-up of a protein called tau and beta-amyloid. Scientists have struggled to develop drugs that reduce levels of either substance, but this new finding suggests good sleep could be the key.

阿爾茨海默病與一種叫做tau和-淀粉樣蛋白的蛋白質的形成有關?？茖W家們一直在努力研發(fā)降低這兩種物質水平的藥物，但這項新發(fā)現(xiàn)表明，良好的睡眠可能是關鍵。

The findings were published in journal Science on Friday.

研究結果發(fā)表在周五的《科學》雜志上。