محفوظ في:
التفاصيل البيبلوغرافية
المؤلفون الرئيسيون: Lyu, Guangtao, Cheng, Xinyi, Liu, Qi, Xu, Chenghao, Yan, Jiexi, Yang, Muli, Fang, Fen, Deng, Cheng
التنسيق: Preprint
منشور في: 2026
الموضوعات:
الوصول للمادة أونلاين:https://arxiv.org/abs/2602.00621
الوسوم: إضافة وسم
لا توجد وسوم, كن أول من يضع وسما على هذه التسجيلة!
_version_ 1866917238637854720
author Lyu, Guangtao
Cheng, Xinyi
Liu, Qi
Xu, Chenghao
Yan, Jiexi
Yang, Muli
Fang, Fen
Deng, Cheng
author_facet Lyu, Guangtao
Cheng, Xinyi
Liu, Qi
Xu, Chenghao
Yan, Jiexi
Yang, Muli
Fang, Fen
Deng, Cheng
contents LVLMs achieve remarkable multimodal understanding and generation but remain susceptible to hallucinations. Existing mitigation methods predominantly focus on output-level adjustments, leaving the internal mechanisms that give rise to these hallucinations largely unexplored. To gain a deeper understanding, we adopt a representation-level perspective by introducing sparse autoencoders (SAEs) to decompose dense visual embeddings into sparse, interpretable neurons. Through neuron-level analysis, we identify distinct neuron types, including always-on neurons and image-specific neurons. Our findings reveal that hallucinations often result from disruptions or spurious activations of image-specific neurons, while always-on neurons remain largely stable. Moreover, selectively enhancing or suppressing image-specific neurons enables controllable intervention in LVLM outputs, improving visual grounding and reducing hallucinations. Building on these insights, we propose Contrastive Neuron Steering (CNS), which identifies image-specific neurons via contrastive analysis between clean and noisy inputs. CNS selectively amplifies informative neurons while suppressing perturbation-induced activations, producing more robust and semantically grounded visual representations. This not only enhances visual understanding but also effectively mitigates hallucinations. By operating at the prefilling stage, CNS is fully compatible with existing decoding-stage methods. Extensive experiments on both hallucination-focused and general multimodal benchmarks demonstrate that CNS consistently reduces hallucinations while preserving overall multimodal understanding.
format Preprint
id arxiv_https___arxiv_org_abs_2602_00621
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Towards Interpretable Hallucination Analysis and Mitigation in LVLMs via Contrastive Neuron Steering
Lyu, Guangtao
Cheng, Xinyi
Liu, Qi
Xu, Chenghao
Yan, Jiexi
Yang, Muli
Fang, Fen
Deng, Cheng
Computer Vision and Pattern Recognition
LVLMs achieve remarkable multimodal understanding and generation but remain susceptible to hallucinations. Existing mitigation methods predominantly focus on output-level adjustments, leaving the internal mechanisms that give rise to these hallucinations largely unexplored. To gain a deeper understanding, we adopt a representation-level perspective by introducing sparse autoencoders (SAEs) to decompose dense visual embeddings into sparse, interpretable neurons. Through neuron-level analysis, we identify distinct neuron types, including always-on neurons and image-specific neurons. Our findings reveal that hallucinations often result from disruptions or spurious activations of image-specific neurons, while always-on neurons remain largely stable. Moreover, selectively enhancing or suppressing image-specific neurons enables controllable intervention in LVLM outputs, improving visual grounding and reducing hallucinations. Building on these insights, we propose Contrastive Neuron Steering (CNS), which identifies image-specific neurons via contrastive analysis between clean and noisy inputs. CNS selectively amplifies informative neurons while suppressing perturbation-induced activations, producing more robust and semantically grounded visual representations. This not only enhances visual understanding but also effectively mitigates hallucinations. By operating at the prefilling stage, CNS is fully compatible with existing decoding-stage methods. Extensive experiments on both hallucination-focused and general multimodal benchmarks demonstrate that CNS consistently reduces hallucinations while preserving overall multimodal understanding.
title Towards Interpretable Hallucination Analysis and Mitigation in LVLMs via Contrastive Neuron Steering
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2602.00621