SGM: Safety Glasses for Multimodal Large Language Models via Neuron-Level Detoxification

Hongbo Wang, AprilPyone MaungMaung, Isao Echizen


Abstract
Disclaimer: Samples in this paper may be harmful and cause discomfort.

Multimodal large language models (MLLMs) enable multimodal understanding but inherit toxic signals from weakly curated pretraining corpora, leading to explicitly toxic outputs, especially under adversarial triggers that late, opaque training-free detoxification methods struggle to handle. We propose SGM, a white-box neuron-level multimodal intervention that acts like safety glasses for toxic neurons: it recalibrates a set of toxicity-associated neurons via expertise-weighted soft suppression, neutralizing harmful cross-modal activations without any parameter updates. We establish MM-TOXIC-QA, a multimodal toxicity data framework, and compare SGM with existing detoxification techniques. Experiments on open-source MLLMs show that SGM mitigates explicit toxicity in standard and adversarial conditions, cutting average harmful rates from 45.0% to 4.5% while preserving fluency and multimodal reasoning. SGM is extensible, and its combined defenses, denoted as SGM*, integrate with existing detoxification methods for stronger safety performance, providing an interpretable, low-cost solution for toxicity-controlled multimodal generation.
Anthology ID:
2026.emnlp-main.61
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
1400–1418
Language:
URL:
https://aclanthology.org/2026.emnlp-main.61/
DOI:
Bibkey:
Cite (ACL):
Hongbo Wang, AprilPyone MaungMaung, and Isao Echizen. 2026. SGM: Safety Glasses for Multimodal Large Language Models via Neuron-Level Detoxification. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 1400–1418, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
SGM: Safety Glasses for Multimodal Large Language Models via Neuron-Level Detoxification (Wang et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.61.pdf