37
(A)They also found that during sleep, the brain’s cells shrink, or become smaller.
(B)While we sleep, our brains are doing much more than getting ready for the next day.
(C)She said the results demonstrate just how important sleep is to health and fighting disease.
(D)The brain expert says our brains perform two very different jobs.

Is bedtime just a time for dreaming?

Do our brains turn off for the night?

What if I told you that scientists recently discovered that our brains may be just as busy at night as they are during the day?

37 Researchers at the University of Rochester found that the brain may be busy cleaning house -- cleaning out harmful waste materials.

As with many studies, the researchers turned to mice for help.

They studied mice that had colored dye染色 injected注射 into their brains.

(A)They also found that during sleep, the brain’s cells shrink變小, （使）縮小, or become smaller. 

(B)While we sleep, our brains are doing much more than getting ready for the next day. 
(C)She said the results demonstrate展示, 顯示；表明 just how important sleep is to health and fighting disease. 

(D)The brain expert says our brains perform two very different jobs. 

Is bedtime just a time for dreaming? Do our brains turn off for the night? What if I told you that scientists recently discovered that our brains may be just as busy at night as they are during the day? 37. While we sleep, our brains are doing much more than getting ready for the next day. Researchers at the University of Rochester found that the brain may be busy cleaning house -- cleaning out harmful waste materials.

Google翻譯：

上床睡覺只是做夢的時間嗎？晚上我們的大腦會關閉嗎？如果我告訴你科學家最近發現晚上的大腦可能和白天一樣忙，那該怎麼辦？雖然我們睡覺，但大腦所做的工作遠遠超過了第二天的準備。羅徹斯特大學的研究人員發現，大腦可能正在忙於打掃房子-清理有害的廢物。