On the same day, the peace from the test center, a blank mind.

当日，安宁从检验中心出来，头脑一片空白。

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If you think that not thinking is the same as having a blank mind, then you're making the error of equating "the mind" with "thinking" and specifically with verbal thinking, or inner self-talk.

如果你认为不思考就等同于空白的心，那么你犯了错误，你在把“心灵”和“想法”，特别是口头的想法、或内心的自白划上等号。

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My mind was a blank and I couldn't remember her name.

我脑子里是一片空白，记不起她的名字了。

《牛津词典》

What if your mind goes blank?

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My mind went blank.

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In a "busy" environment, I will eventually go into sensory overload and my mind will go blank.

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