The Inner Monologue of Language Models: When Reasoning Traces Reveal More Than They Hide

Pratham Singla, Shivank Garg, Ayush Singh, Ishan Garg, Ketan Suhaas Saichandran


Abstract
Recent advances in post-training techniques have endowed Large Language Models (LLMs) with enhanced capabilities for tackling complex, logic-intensive tasks through the generation of supplementary planning tokens. This development raises a fundamental question – Are these models aware of what they "learn” and "think”? To address this, we define three core competencies: (1) awareness of learned latent policies, (2) generalization of these policies across domains, and (3) alignment between internal reasoning traces and final outputs. We empirically evaluate these abilities on several tasks, each designed to require learning a distinct policy. Furthermore, we contrast the profiles of models post-trained via Supervised Fine-Tuning (SFT), Direct Policy Optimization (DPO), and Group Relative Policy Optimization (GRPO). Our findings indicate that RL-trained models not only demonstrate greater awareness of their learned behaviors and stronger generalizability to novel, structurally similar tasks than SFT models but also often exhibit weak alignment between their reasoning traces and final outputs, an effect most pronounced in GRPO-trained models.
Anthology ID:
2026.findings-acl.2078
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
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Pages:
41864–41889
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URL:
https://preview.aclanthology.org/ingest-acl-workshops/2026.findings-acl.2078/
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Bibkey:
Cite (ACL):
Pratham Singla, Shivank Garg, Ayush Singh, Ishan Garg, and Ketan Suhaas Saichandran. 2026. The Inner Monologue of Language Models: When Reasoning Traces Reveal More Than They Hide. In Findings of the Association for Computational Linguistics: ACL 2026, pages 41864–41889, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
The Inner Monologue of Language Models: When Reasoning Traces Reveal More Than They Hide (Singla et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl-workshops/2026.findings-acl.2078.pdf
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