Effects of social exclusion on self-disclosure: The roles of interpersonal trust and attribution style

Social exclusion is a common yet understudied phenomenon from the observer's perspective. This study examines how witnessing exclusion affects individuals' willingness to self-disclose and explores the mediating role of interpersonal trust and the moderating role of attribution style. In Study 1, participants exposed to observed exclusion reported significantly lower self-disclosure than those in inclusion conditions. Studies 2a and 2b confirmed that interpersonal trust mediated this effect. Study 3 further showed that attribution style moderated the impact of observed exclusion on trust: trust declined more sharply under external attribution than internal attribution. These findings extend Communication Privacy Management Theory and the Social Information Processing Model, highlighting the cognitive mechanisms by which observers regulate disclosure following exclusion.