arXiv Computation and Language

Beyond the Evidence Boundary: Behavioral Mirage Under Progressive Degradation in Medical VLMs

arXiv AI
Sep 18

Correct Now, Insufficient Later: Auditing Update Sufficiency in Context Compression

The paper investigates how memory systems can answer a current query correctly yet fail to retain distinctions needed for later updates. Using a paired‑history audit, the authors evaluate 24 history pairs across six synthetic mechanisms and two model backends, achieving perfect reveal accuracy on DeepSeek and high accuracy on GLM. Record‑level audits reveal specific failures in structured reveal memories and frontier late‑reference adequacy, and the authors test a label‑equivariant repair that only partially restores correctness.

By Guangzhe Zhang
arXiv AI
Jul 21

Med-OPD: Improving Medical Vision-Language Models via Evidence-Aware On-Policy Distillation

arXiv:2607. 16303v1 Announce Type: cross Abstract: Medical Vision-Language Models (Med-VLMs) require reliable reasoning from fine-grained visual evidence, yet existing models can produce plausible clinical answers by relying on language priors or medical templates rather than truly attending to diagnosis-critical regions.

By Yunhang Qian, Jiaquan Yu, Jiawei Liu, Meng Wang, Hongwei Bran Li, Xiaobin Hu
arXiv AI
Oct 27

Conviction Without Evidence: Verdict Stability Is Independent of Visual Grounding in Medical Vision--Language Models

Vision–language models can correctly diagnose medical questions using only the clinical vignette, without the diagnostic image. In experiments on 60 Italian State Examination items, models defended diagnoses derived from a blank placeholder as firmly as those derived from real images, showing no increased fragility. While different adversarial pressures produced distinct dynamics—one leading to a single decisive flip and the other to continual changes—the instability under contentless doubt reflected item ambiguity rather than lack of evidence.

By Federico Felizzi, Francesco Andrea Causio, Bianca Destro Castaniti, Olivia Riccomi, Michele Ferramola, Vittorio De Vita, Alessandro Tosi, Antonio Cristiano, Alessia Longo, Lorenzo De Mori, Chiara Battipaglia, Melissa Sawaya, Luigi De Angelis, Marcello Di Pumpo, Alessandra Piscitelli, Pietro Eric Risuleo, Giulia Vojvodic, Mariapia Vassalli, Nicolo Scarsi, Manuel Del Medico
arXiv AI
Oct 26

Beyond Discrete Tokens: Preserving Numerical Continuity in Medical Vision-Language Models

The paper introduces HAD‑VLM, a hybrid autoregressive‑diffusion vision‑language model that jointly generates text prompts and predicts continuous ultrasound measurements. By tuning the vision encoder with visual prompts and employing a diffusion process to output caliper coordinates and lengths, the model achieves lower mean absolute errors on four echocardiographic tasks compared to autoregressive and fine‑tuned baselines. It also maintains medical question‑answering performance and improves vertebral measurement accuracy on X‑ray data.

By Dianye Huang, Jiamei Guo, Yue Zhou, Mingde Li, Yi Xiong, Wei Wang, Nassir Navab, Zhongliang Jiang