The scientists hope that understanding brain scans during sleep will enable researchers to develop tools to keep us asleep when we want to sleep and to wake us up only when it is time.

科学家们希望，在睡眠中对脑部已知功能区域的扫描能够让研究者们开发出一些工具，让我们在想要睡觉的时候保持困倦状态，该起床的时候自然起床。

youdao

They think they should sleep 8 or 9 hr., so they spend [that amount of time] in bed, with the result that they have trouble falling asleep and wake up a lot during the night.

他们认为应该睡8或9个小时，应此一定要花这么久的时间待在床上，这样的结果是很难进入梦乡或者是半夜就醒了。

youdao