By scanning the boys twice the scientists were able to create a detailed picture of how the brain changes during this critical period of development.

通过对这些男孩的两次扫描，科学家可以细致地描绘出在这个重要的发育时期，大脑是如何变化的。

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She thinks there's a critical period in early childhood when the lack of sleep is particularly detrimental to development, even if sleep habits improve later on.

她认为，幼童时期中存在一个关键阶段，在这一阶段缺乏睡眠对孩子的成长尤为不利，即使他们今后的睡眠习惯有所改善也无法补救。

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Results The period of 0-2 years old was the critical stage for babies' language development during intelligence development of 3 years.

结果在0~3岁婴幼儿的智力发育中，0~2岁是婴幼儿语言发育的关键时期；

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This suggests that there is a critical period in the development of the brain when the bacteria are influential.

FORBES: Thinking With Your Gut. Literally.