On a 6,400-sample multi-turn ECG benchmark, models knew the clinical criteria for a diagnosis but consistently failed to ground the findings in the signal itself
AspireAI community · arXiv (NeurIPS 2026 Evaluations & Datasets)
Multimodal language models score well on automated electrocardiogram interpretation, but it is unclear whether they reason step by step or rely on superficial visual cues. ECG-Reasoning-Benchmark is a multi-turn evaluation framework of more than 6,400 samples spanning 17 core ECG diagnoses, and the evaluation of state-of-the-art models reveals a systematic shortfall in executing multi-step logical deduction: models retrieve the right clinical criteria for a diagnosis but keep the reasoning chain intact poorly, primarily failing to ground the corresponding findings to the actual visual evidence in the ECG signal, which the authors read as current models bypassing visual interpretation altogether. Code and data are available, and the benchmark was accepted to the NeurIPS 2026 Evaluations and Datasets Track.
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