Saved in:
Bibliographic Details
Main Authors: Pan, Zhikai, Liao, Chih-Ting, Liu, Chunrui, Xiao, Xi, Qiao, Yitong, Meng, Chunlei, Chen, Zhangquan, Cao, Xin
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2605.28277
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913168066871296
author Pan, Zhikai
Liao, Chih-Ting
Liu, Chunrui
Xiao, Xi
Qiao, Yitong
Meng, Chunlei
Chen, Zhangquan
Cao, Xin
author_facet Pan, Zhikai
Liao, Chih-Ting
Liu, Chunrui
Xiao, Xi
Qiao, Yitong
Meng, Chunlei
Chen, Zhangquan
Cao, Xin
contents Whether large language models (LLMs) construct internal spatial world models from pure-text descriptions remains contested, and whether such capabilities transfer across languages has not been systematically studied. We introduce MentalMap, a multilingual diagnostic benchmark with a six-level capability hierarchy (L0-L5) spanning atomic spatial facts to generative world-graph construction, together with four diagnostic axes probing frame of reference, reading-direction bias, reasoning-effort allocation, and hallucination. MentalMap is built from 100 ProcTHOR household scenes, covers eight typologically diverse languages plus a structured-text control, and contains 39 task families across 1,950 evaluation cells. Evaluating thirteen LLMs across scales and model families, we identify a universal L3 reasoning cliff: no model retains even half of its L0 performance on viewpoint reasoning once baseline atomic accuracy exceeds 40%. The cliff persists across languages, scales, and prompting strategies, while structured-output failures and reasoning patterns vary substantially across models. Human evaluation under the identical pure-text protocol reproduces the same failure pattern, suggesting that the bottleneck arises from text-only working memory constraints rather than being specific to current LLM architectures. Our findings reframe pure-text spatial reasoning as a multi-axis world-modeling problem and motivate multimodal and scratchpad-augmented reasoning as future directions.
format Preprint
id arxiv_https___arxiv_org_abs_2605_28277
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Do LLMs Build World Models From Text? A Multilingual Diagnostic of Spatial Reasoning
Pan, Zhikai
Liao, Chih-Ting
Liu, Chunrui
Xiao, Xi
Qiao, Yitong
Meng, Chunlei
Chen, Zhangquan
Cao, Xin
Artificial Intelligence
Whether large language models (LLMs) construct internal spatial world models from pure-text descriptions remains contested, and whether such capabilities transfer across languages has not been systematically studied. We introduce MentalMap, a multilingual diagnostic benchmark with a six-level capability hierarchy (L0-L5) spanning atomic spatial facts to generative world-graph construction, together with four diagnostic axes probing frame of reference, reading-direction bias, reasoning-effort allocation, and hallucination. MentalMap is built from 100 ProcTHOR household scenes, covers eight typologically diverse languages plus a structured-text control, and contains 39 task families across 1,950 evaluation cells. Evaluating thirteen LLMs across scales and model families, we identify a universal L3 reasoning cliff: no model retains even half of its L0 performance on viewpoint reasoning once baseline atomic accuracy exceeds 40%. The cliff persists across languages, scales, and prompting strategies, while structured-output failures and reasoning patterns vary substantially across models. Human evaluation under the identical pure-text protocol reproduces the same failure pattern, suggesting that the bottleneck arises from text-only working memory constraints rather than being specific to current LLM architectures. Our findings reframe pure-text spatial reasoning as a multi-axis world-modeling problem and motivate multimodal and scratchpad-augmented reasoning as future directions.
title Do LLMs Build World Models From Text? A Multilingual Diagnostic of Spatial Reasoning
topic Artificial Intelligence
url https://arxiv.org/abs/2605.28277