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arXiv AI By Maverick Morales, Tom\'a\v{s} Dominik, Vermut Gao, Katrina Shirey, Paulius Rimkevi\v{c}ius, Aaron Schurger, Uri Maoz

Reasoning-Token Spikes Under Prompted Untruthful Responses in Large Language Models

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The study investigates whether the number of reasoning tokens produced by large language models can signal untruthful responses. Researchers prompted three models to answer 210 multiple‑choice questions under instructions to be truthful, deceptive, or indifferent, and found that truth‑directed answers consistently used fewer reasoning tokens than lie‑directed or indifferent ones. The results suggest that token count could serve as a simple, content‑independent indicator of untruthful behavior when full reasoning traces are unavailable.

Machine-generated by The Flow from the publisher's headline and feed description — not written or checked by a human. The full article lives at arXiv AI.

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