Addressing the Reasoning Gap: Mechanistic Circuit-Based Knowledge Editing in Large Language Models

Tianyi Zhao, Yinhan He, Wendy Zheng, Chen Chen


Abstract
Deploying Large Language Models (LLMs) in real-world dynamic environments raises the challenge of updating their pre-trained knowledge. While existing knowledge editing methods can reliably patch isolated facts, they frequently suffer from a reasoning gap, where the model recalls the edited fact but fails to utilize it in multi-step reasoning chains. Our analysis shows that multi-hop reasoning relies on sparse circuitry beyond direct factual recall, with functionally differentiated components contributing to intermediate processing and final-answer prediction. To bridge this gap, we introduce MCircKE (Mechanistic Circuit-based Knowledge Editing), a mechanistically grounded framework that enables a map-and-adapt editing procedure. MCircKE first identifies the causal circuits responsible for a specific reasoning task, capturing both the storage of the fact and the routing of its logical consequences. It then surgically update parameters exclusively within this mapped circuit. Extensive experiments on the MQuAKE-series benchmarks demonstrate the effectiveness of the proposed method for multi-hop reasoning in knowledge editing.
Anthology ID:
2026.findings-emnlp.303
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
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SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
6426–6439
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URL:
https://aclanthology.org/2026.findings-emnlp.303/
DOI:
Bibkey:
Cite (ACL):
Tianyi Zhao, Yinhan He, Wendy Zheng, and Chen Chen. 2026. Addressing the Reasoning Gap: Mechanistic Circuit-Based Knowledge Editing in Large Language Models. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 6426–6439, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Addressing the Reasoning Gap: Mechanistic Circuit-Based Knowledge Editing in Large Language Models (Zhao et al., Findings 2026)
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https://aclanthology.org/2026.findings-emnlp.303.pdf