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Why Do We Sleep?
Dear A Moment of Science,
Why do we sleep? I know this question has been debated by scientists and philosophers for centuries, but are there any hard and fast answers?
Good question! First, it’s true that scientists have long pondered the mystery of sleep why we do it and why it’s necessary. We know that going without sleep for too long can seriously damage health, so there’s good reason to believe that getting enough sleep is important for our well-being.
But exactly how and why that’s the case is still an open question. Some research, though, may shed a little light on the problem. For instance, scientists at the University of Rochester Medical Center in New York did a study with mice, and found that during sleep their brains flush out toxins that accumulate during the day.
More specifically, the study found that sleep sort of changes the brain’s cellular structure. When the mice were asleep or anesthetized, the researchers found that there was more space between their brain cells, allowing a sort of brain plumbing apparatus called the glymphatic system to open wide and allow fluid to flow quickly through the brain.
Other studies have shown that toxic molecules build up in the space between brain cells. Researchers at the University of Rochester found that those molecules vanished faster from the brain when the mice were asleep.
So what does this mean? Well, it could give scientists new ways to study and potentially treat brain disorders like Alzheimer’s by targeting the glymphatic system and helping it better flush away brain toxins.
我們?yōu)槭裁葱枰X？
親愛的《科學一科》欄目組：
我們?yōu)槭裁葱枰X？我知道科學家們和哲學家們就這個問題爭論了好幾個世紀，但現(xiàn)在有沒有確實的，現(xiàn)成的答案？
問得好！首先，科學家們長期以來確實在思考睡眠這一謎題，我們?yōu)槭裁葱枰?，為什么睡眠十分必要？我們知道長期失眠會嚴重的危害健康，因此，有必要相信保證睡眠充足對健康很重要。
但失眠為什么會影響健康，又是如何影響的，這個問題仍沒有答案。一些研究也許可以稍稍解答這個問題。比如，紐約羅切斯特大學醫(yī)學中心的科學家們用老鼠做了一個研究，發(fā)現(xiàn)老鼠在睡覺時，他們的大腦會排除白天積累的毒素。
更確切的說，該研究發(fā)現(xiàn)睡眠在某種程度上改變了大腦的細胞結構。當老鼠處于睡眠狀態(tài)或被麻醉是，研究人員發(fā)現(xiàn)，他們大腦細胞之間的空間增大了，使被稱為腦部類淋巴系統(tǒng)的類似排污管道的器官大大的打開，這樣腦脊液就能在大腦中快速的流動。
其他的研究表明，有毒分子在腦細胞的間隙中生成。羅切斯特大學的研究人員發(fā)現(xiàn)，這些分子在老鼠睡覺時從大腦中消失得更快。
所以，這意味著什么呢？這意味著通過針對腦部類淋巴系統(tǒng)可以幫助大腦更好的排除腦部毒素，使科學家們有新的方法研究并很有可能治好像老年癡呆癥這樣的大腦疾病。
Why Do We Sleep?
Dear A Moment of Science,
Why do we sleep? I know this question has been debated by scientists and philosophers for centuries, but are there any hard and fast answers?
Good question! First, it’s true that scientists have long pondered the mystery of sleep why we do it and why it’s necessary. We know that going without sleep for too long can seriously damage health, so there’s good reason to believe that getting enough sleep is important for our well-being.
But exactly how and why that’s the case is still an open question. Some research, though, may shed a little light on the problem. For instance, scientists at the University of Rochester Medical Center in New York did a study with mice, and found that during sleep their brains flush out toxins that accumulate during the day.
More specifically, the study found that sleep sort of changes the brain’s cellular structure. When the mice were asleep or anesthetized, the researchers found that there was more space between their brain cells, allowing a sort of brain plumbing apparatus called the glymphatic system to open wide and allow fluid to flow quickly through the brain.
Other studies have shown that toxic molecules build up in the space between brain cells. Researchers at the University of Rochester found that those molecules vanished faster from the brain when the mice were asleep.
So what does this mean? Well, it could give scientists new ways to study and potentially treat brain disorders like Alzheimer’s by targeting the glymphatic system and helping it better flush away brain toxins.
我們?yōu)槭裁葱枰X？
親愛的《科學一科》欄目組：
我們?yōu)槭裁葱枰X？我知道科學家們和哲學家們就這個問題爭論了好幾個世紀，但現(xiàn)在有沒有確實的，現(xiàn)成的答案？
問得好！首先，科學家們長期以來確實在思考睡眠這一謎題，我們?yōu)槭裁葱枰?，為什么睡眠十分必要？我們知道長期失眠會嚴重的危害健康，因此，有必要相信保證睡眠充足對健康很重要。
但失眠為什么會影響健康，又是如何影響的，這個問題仍沒有答案。一些研究也許可以稍稍解答這個問題。比如，紐約羅切斯特大學醫(yī)學中心的科學家們用老鼠做了一個研究，發(fā)現(xiàn)老鼠在睡覺時，他們的大腦會排除白天積累的毒素。
更確切的說，該研究發(fā)現(xiàn)睡眠在某種程度上改變了大腦的細胞結構。當老鼠處于睡眠狀態(tài)或被麻醉是，研究人員發(fā)現(xiàn)，他們大腦細胞之間的空間增大了，使被稱為腦部類淋巴系統(tǒng)的類似排污管道的器官大大的打開，這樣腦脊液就能在大腦中快速的流動。
其他的研究表明，有毒分子在腦細胞的間隙中生成。羅切斯特大學的研究人員發(fā)現(xiàn)，這些分子在老鼠睡覺時從大腦中消失得更快。
所以，這意味著什么呢？這意味著通過針對腦部類淋巴系統(tǒng)可以幫助大腦更好的排除腦部毒素，使科學家們有新的方法研究并很有可能治好像老年癡呆癥這樣的大腦疾病。