[https://en.wikipedia.org/wiki/Semantic_satiation](https://en.wikipedia.org/wiki/Semantic_satiation)
It’s called semantic satiation. I don’t think we know the real answer, but there are some ideas. One is that repeatedly activating whatever neural patterns represent a word causes the brain to inhibit that pattern. This could happen to the sound itself (the recognition of the sound of the word) OR the actual meaning of the word in the brain. But yeah, I don’t think we have conclusive answers.
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