I suppose the shock had addled his poor old brain.

我想这个打击已经使他可怜的老脑筋变糊涂了。

《柯林斯英汉双解大词典》

How did that eight-year-old brain of yours find its way around a big word like "overcapitalized"?

你八岁的小脑瓜是怎么琢磨出“过度投资”这样的大词的？

youdao

The old brain makes or at least has input into most of our decisions.

老脑帮我们做决策，或说至少参与了决策。

youdao

"She's With Me" was inspired by his eight-year-old granddaughter Haley, who has a rare degenerative brain disorder.

VOA: standard.2009.08.04

The immediate reaction is the old brain, and the old brain functions in its own traditional, accepted, reactionary, animalistic sense.

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As patients age, genetic mutations or unknown environmental factors may boost the production of deformed proteins, or old brain cells simply may become less able to dispose of debris.

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The old brain is a superb pattern-recognizer.

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