Identification of protective factors for externalizing outcomes such as aggression and alcohol-related consequences serves to inform prevention and intervention programs. Prior research has demonstrated that social reminiscing might serve a protective function for externalizing outcomes in childhood, theorized to function through reduced emotion dysregulation and increased autobiographical memory specificity. However, research has not yet examined these relationships among emerging adults. The present study examined whether social reminiscing was associated with fewer externalizing outcomes among emerging adults including aggression and alcohol-related consequences, as mediated by emotion dysregulation and autobiographical memory specificity. Undergraduate students (N = 404) attending a predominantly White, Midwestern university completed an online autobiographical memory task and self-report survey. Structural equation modeling (SEM) revealed that more social reminiscing was directly related to less emotion dysregulation and indirectly related to less reactive aggression, proactive aggression, and alcohol-related consequences as mediated by emotion dysregulation. Additional exploratory SEM accounting for posttraumatic stress symptoms in response to the COVID-19 pandemic revealed that more social reminiscing was directly related to less emotion dysregulation and indirectly related to less reactive aggression as mediated by emotion dysregulation, but social reminiscing was not related to proactive aggression or alcohol-related consequences. With and without accounting for posttraumatic stress, autobiographical memory specificity was not related to social reminiscing, emotion dysregulation, reactive aggression, proactive aggression, or alcohol-related consequences. The present results provide initial support for social reminiscing as a protective factor for emotion dysregulation, and consequently, externalizing outcomes such as aggression and alcohol-related consequences among emerging adults. Though, posttraumatic stress in response to the COVID-19 pandemic complicates these relationships. Future research should examine whether targeting social reminiscing decreases emotion dysregulation and externalizing outcomes. Further, future research should consider the impact of posttraumatic responses to the COVID-19 pandemic on relationships between social reminiscing, emotion dysregulation, and externalizing outcomes
