In a new study published in Nature Human Behavior, scientists found that our brains are still paying attention while we're asleep. They played human speech, and a type of jibberish called Jabberwocky, to sleeping people and saw that brain activity reflected the speech and not the Jabberwocky.

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In a new study published in Nature Human Behavior, scientists found that our brains are still paying attention while we're asleep. They played human speech, and a type of jibberish called Jabberwocky, to sleeping people and saw that brain activity reflected the speech and not the Jabberwocky.