Yawning additionally appears to facilitate transitional states of the brain, such as going from sleep to waking periods.

呵欠还起到了使大脑状态过度顺畅的作用，比如从睡眠状态到清醒状态切换时。

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Yawning additionally appears to facilitate transitional states of the brain, such as going from sleep to waking periods.

呵欠还起到了使大脑状态过度顺畅的作用，比如从睡眠状态到清醒状态切换时。

youdao