Words Caught in the Heart: Simulating Person-Specific Expression for Self-Opaque Clients in Psychotherapy

Researchers have proposed Pandora, a psychotherapy client simulation framework that models how psychological experience becomes individual expression by updating psychological and relational states in response to therapist interventions. Pandora constructs subjective appraisals and attributions, plans response content and strategy, and uses a separate expression planner to combine these decisions with language patterns from client utterances, achieving the highest expression similarity and overall disclosure-alignment score among five baselines evaluated on 115 cases from four counseling and motivational interviewing datasets.