Multi-Faceted Interactivity Alignment in Full-Duplex Speech Models

Atsumoto Ohashi, Neil Zeghidour, Alexandre Défossez, Eugene Kharitonov


Abstract
Full-duplex spoken dialogue models can listen and speak simultaneously, making them a promising architecture for natural conversation. However, current models are trained solely with supervised learning through token-level likelihood maximization, which does not directly optimize interaction-level behaviors, causing interactivity issues such as excessive silence and ill-timed turn-taking. Recent work has applied reinforcement learning (RL) to improve interactivity, but existing methods address only a limited set of interactive behaviors in their rewards. In this work, we propose a post-training alignment method that comprehensively improves the interactivity of full-duplex spoken dialogue models through RL. We address the four canonical axes of interactivity: pause handling, turn-taking, backchanneling, and user interruption. For each axis, we extract short audio segments from human conversation corpora and optimize the model with axis-specific reward functions. An extra LLM-based reward for response quality prevents semantic degradation. We apply our method to two open-source models, Moshi and PersonaPlex, demonstrating consistent improvements in interactivity on both offline evaluation with pre-recorded audio and real-time multi-turn dialogue evaluation.
Anthology ID:
2026.emnlp-main.2331
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:
52949–52965
Language:
URL:
https://aclanthology.org/2026.emnlp-main.2331/
DOI:
Bibkey:
Cite (ACL):
Atsumoto Ohashi, Neil Zeghidour, Alexandre Défossez, and Eugene Kharitonov. 2026. Multi-Faceted Interactivity Alignment in Full-Duplex Speech Models. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 52949–52965, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Multi-Faceted Interactivity Alignment in Full-Duplex Speech Models (Ohashi et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.2331.pdf