Language Diffusion Models are Associative Memories Capable of Retrieving Unseen Data

Bao Pham, Mohammed J Zaki, Luca Ambrogioni, Dmitry Krotov, Matteo Negri


Abstract
Understanding when language diffusion models memorize training data versus generalize remains an open challenge. We address it by framing Uniform-based Discrete Diffusion Models (UDDMs) as Associative Memories (AMs) where **both memorization and creativity coexist**. Unlike Hopfield networks, which require an energy function to produce attractors, we show that attractors can be formed via conditional likelihood maximization. We observe that UDDMs treat both training and unseen test sequences as fixed points for denoising while retaining the capacity to synthesize novel texts. We demonstrate that, as training set size increases, attractor basins around training samples shrink while those around unseen test samples expand until they become indistinguishable. This transition can be detected via the conditional entropy of tokens, which vanishes during memorization. Our framework provides both a theoretical foundation and a practical metric to elucidate the generative regimes of UDDMs.
Anthology ID:
2026.emnlp-main.835
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
19377–19404
Language:
URL:
https://aclanthology.org/2026.emnlp-main.835/
DOI:
Bibkey:
Cite (ACL):
Bao Pham, Mohammed J Zaki, Luca Ambrogioni, Dmitry Krotov, and Matteo Negri. 2026. Language Diffusion Models are Associative Memories Capable of Retrieving Unseen Data. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 19377–19404, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Language Diffusion Models are Associative Memories Capable of Retrieving Unseen Data (Pham et al., EMNLP 2026)
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https://aclanthology.org/2026.emnlp-main.835.pdf