When Situations Take Effect: Psychological Situation Modulation for Personalized Dialogue Generation

Personalized dialogue should reflect users’ facts, personality, affect, and situation. Existing situation representations focus on physical and social circumstances, overlooking psychological appraisals. Personality, affect, and memory also lack joint integration in response generation and dedicated evaluation. We propose PSyMod, a Psychological Situation Modulation framework that constructs a frozen persistent state for each user, comprising episodic memory, a personality profile, and a situational reference distilled from past experiences. During generation, psychological situation modulates memory retrieval, personality expression, and response planning, while turn-level affect controls expressive intensity. Our benchmark and evaluation protocol separately assess response generation, state construction, and closed-loop operation. PSyMod outperforms the strongest evaluated condition in ESC-based response quality and situation-modulation consistency, particularly for personality expression and memory use, but scores slightly lower in a blind four-dimensional review. It also maintains competitive retrieval performance without storing hallucinated entries in our evaluation.