S-Space: Exploring Spatial Workspace in Multimodal Language Models
Multimodal language models (MLLMs) exhibit promising spatial reasoning capabilities, yet the internal mechanisms supporting them remain poorly understood.

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Key points
- We uncover S-Space, a linear representation subspace in which object-token representations encode continuous coordinates along horizontal, vertical, and distance axes.
- Although we identify these axes by differentiating spatial-answer scores with respect to object-token activations, S-Space is intrinsic rather than induced by specific data or prompts, remaining readable under non-spatial questions.
- We show that S-Space functions as an internal spatial workspace of MLLMs. Perception encodes object locations into it, forming spatial representations that can be directly read out to support accurate spatial judgments.
- Direction-word readouts reveal systematic coupling between cardinal and image-relative reference frames.
Sources (2)
- [1]S-Space: Exploring Spatial Workspace in Multimodal Language ModelsarXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 9, 12:48 PM
Multimodal language models (MLLMs) exhibit promising spatial reasoning capabilities, yet the internal mechanisms supporting them remain poorly understood.
We uncover S-Space, a linear representation subspace in which object-token representations encode continuous coordinates along horizontal, vertical, and distance axes.
- [2]S-Space: Exploring Spatial Workspace in Multimodal Language ModelsHugging Face Daily Papers · Oct 9, 12:48 PM · same content
Extractive summary: sentences quoted from the sources.