π€ AI Summary
This work addresses the perceptual-action gap in multimodal large language models, which struggle to generate context-consistent actions under identical visual inputs. To this end, the authors introduce the ROSE benchmarkβa novel evaluation framework that isolates perceptual-action consistency by holding visual inputs constant while varying region constraints and symbolic output requirements, thereby assessing fine-grained visual reasoning and action generation against implicit majority references. Through controlled tasks such as counting-coordinate coupling and global-click versus local-matching, experiments across nine state-of-the-art models reveal a performance drop of up to 44.5 percentage points in region-conditioned action tasks compared to counting, despite human accuracy reaching 98.8%. These findings expose a significant context-induced performance discontinuity and a task-specific bottleneck independent of localization capability.
π Abstract
Multimodal large language models (MLLMs) are increasingly expected to act on visual information, yet the same scene may require different actions under different task contexts. How reliably can a model turn the same visual evidence into the action required by the current context? To answer this question, we introduce \textsc{ROSE} (\textbf{R}eference-conditioned \textbf{O}ddity and \textbf{S}ymbolic \textbf{E}xecution), a controlled benchmark that holds the visual scene fixed while varying region constraints and required symbolic outputs. Through coupled counting and coordinate-action tasks, \textsc{ROSE} tests whether models can infer an implicit majority reference and act on the resulting fine-grained visual evidence under changing contexts. Across nine recent MLLMs, performance drops by as much as 44.5 percentage points from counting-oriented tasks to region-conditioned action, despite 98.8\% human performance. The gap persists on paired scenes and regions for which the same model returns the correct count, while global-click and matched local controls show that coordinate grounding explains only part of the loss, revealing a distinct, model-dependent bottleneck in turning shared visual evidence into context-specific actions.