Attend to Evidence: Evidence-Anchored Spatial Attention Supervision for Multimodal RLVR

Ruina Hu, Chen Wang, Lai Wei, Bai Jionghao, Bin Yu, Weiran Huang, Kai Wang, Yue Wang


Abstract
Reinforcement learning with verifiable rewards (RLVR) improves vision-language models (VLMs) by optimizing outcome rewards derived from final answers. However, such outcome-only rewards do not tell the model which image regions justify an answer. For questions that require visual grounding, these rewards cannot distinguish responses supported by relevant visual evidence from those produced by language-prior shortcuts or lucky guesses. We introduce **EASE** (Evidence-Anchored Spatial Attention), which augments multimodal RLVR with visual-evidence process supervision. EASE converts annotated evidence regions into a smoothed visual-token target and uses it to guide response-to-image attention during RL training, but only on high-reward trajectories. The annotations are used solely as privileged training labels, while inference requires only the original image and question. Across Qwen2.5-VL-7B, Qwen3-VL-4B, and Qwen3-VL-8B, EASE raises average scores over DAPO by 2.5 to 3.1 points on perception, hallucination, visual math, and multimodal reasoning benchmarks. Diagnostics and ablations show that EASE better aligns visual attention with annotated evidence regions. Code are available at https://github.com/Nrich-sunny/Attend-to-Evidence/.
Anthology ID:
2026.findings-emnlp.204
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
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
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Pages:
4295–4313
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.204/
DOI:
Bibkey:
Cite (ACL):
Ruina Hu, Chen Wang, Lai Wei, Bai Jionghao, Bin Yu, Weiran Huang, Kai Wang, and Yue Wang. 2026. Attend to Evidence: Evidence-Anchored Spatial Attention Supervision for Multimodal RLVR. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 4295–4313, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Attend to Evidence: Evidence-Anchored Spatial Attention Supervision for Multimodal RLVR (Hu et al., Findings 2026)
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PDF:
https://aclanthology.org/2026.findings-emnlp.204.pdf