意見交渉の過程における「本題から逸れる話」の類型と特徴 - 日本語母語話者大学生の会話データに基づく分析 -

This study aims to examine “off-topic conversation” observed in the process of opinion negotiation, focusing on its forms and characteristics. The data consist of conversations among three native Japanese university students who share a close relationship, providing a naturalistic interactional context. The analysis classifies off-topic conversations into four forms: (1) humor/joking, (2) sharing episodes, (3) information provision, and (4) meta-commentary. The findings reveal that these utterances are not merely peripheral or trivial, but that sustain and facilitate the flow of negotiation discourse. Specifically, they contribute to maintaining conversational coherence through processes such as returning to the main topic, closing with brief affiliative responses, and shifting to new topics, while also reducing tension and adjusting interpersonal relationships. Furthermore, given that the participants were in a close relationship, off-topic conversations tended to emerge more naturally and manifest in diverse ways, suggesting that relational closeness plays a crucial role in shaping its occurrence and functions.