A training-free plugin cut multimodal hallucinations by tracing clues from the question backwards
AspireAI community · arXiv (EMNLP 2026 Oral)
Large multimodal reasoning models gather visual clues and decode them into text, and that long chain gives hallucinations more room - the model drifts toward question-irrelevant entities and its reasoning decouples from the image. The authors name this reasoning drift and argue it is why inference-time localisation methods built for non-reasoning models fail to find the true clues here. ClueTracer starts from the question and traces how key clues propagate along the reasoning pathway (question to outputs to visual tokens), localising task-relevant patches while suppressing attention to irrelevant regions. It is training-free, parameter-free and architecture-agnostic, and the paper reports a 1.21x improvement on reasoning benchmarks for architectures including R1-OneVision, Ocean-R1 and MM-Eureka. It was accepted as an EMNLP 2026 oral.
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