We investigated whether the relationship between partisan YouTube channel use and conspiracy mentality depends on like-minded discussion and interest in politics. Using a two-wave panel survey conducted around South Korea’s 2024 general election (Wave 1: N = 1,550; Wave 2: N = 908) and lagged regression models controlling for prior conspiracy mentality, partisan YouTube channel use showed no direct association with conspiracy mentality. The association between partisan channel use and conspiracy mentality strengthened as like-minded discussion increased, and this pattern weakened as political interest increased. The three-way pattern emerged for liberal partisan channels but not for conservative partisan channels, indicating ideological asymmetry in the conditional association. Overall, the findings suggest that partisan YouTube channel use relates to conspiracy mentality mainly when users frequently engage in like-minded discussions and have lower interest in politics. The results also highlight that interaction and discussion settings are central on the YouTube platform for understanding when partisan channel use is associated with conspiracy mentality.
