Virtual Agent for Real-Time Motivational Interviewing by Integrating Adaptive Nonverbal Behavior and Language Models
Journal of Visualized Experiments. 2025-12-23; (226):
DOI: 10.3791/69254
Galland L(1), Younsi N(2), Baudonne C(3), Chaby L(4), Helme-Guizon A(5), Pecune
F(6), Pelachaud C(7).
Author information:
(1)ISIR – Sorbonne University; .
(2)ISIR – Sorbonne University.
(3)University of Bordeaux, cours de la Libération.
(4)Vision Action Cognition, Université Paris Cité.
(5)University of Grenoble Alpes, Grenoble INP, CERAG.
(6)CNRS – SANPSY, University of Bordeaux.
(7)CNRS – ISIR, Sorbonne University.
The growing demand for therapeutic support increasingly exceeds the capacity of
available professionals. A virtual agent capable of performing motivational
interviewing (MI) offers a promising solution to assist patients in reaching
their goal of behavior change between sessions with human therapists. MI is
inherently a cooperative and adaptive form of communication. Therefore,
developing an agent capable of adapting its conversational strategies to the
context could significantly enhance the effectiveness of therapy. During MI
sessions, human therapists adjust both their verbal and nonverbal behaviors
based on the human patients’ responses, as well as their profiles. Depending on
the patient’s level of motivation, the therapist will modify their approach
accordingly. Thus, personalization and adaptability are essential for developing
effective MI virtual agents. In this paper, we present a virtual agent capable
of conducting MI sessions by dynamically adapting verbally and nonverbally to
users in real time. Leveraging state-of-the-art models, this system enables MI
interactions. The virtual agent is embodied using the Greta 2.0 platform. Its
nonverbal behavior is generated through a diffusion model called MODIFF, which
adapts to the user’s facial expressions and their readiness to change. These
facial expressions were learned on an MI corpus and validated through a
dedicated user study. The dialogue is generated using a state-of-the-art large
language model (LLM), enhanced by a dialogue manager specifically designed for
MI, with a reinforcement learning approach, and validated through user testing.
Furthermore, the dialogue manager is able to adapt to different user profiles.
The resulting platform is open-source and facilitates the generation of
real-time, multimodal MI dialogues, providing new tools for digitally mediated
therapeutic interactions.
DOI: 10.3791/69254
PMID: 41525230 [Indexed for MEDLINE]