The current dissertation focused on the risks and rewards of the digital context in adolescent romantic relationships. Adolescent romantic relationships are a pivotal developmental milestone and a foundation for future relationship functioning. Thus, it is vital to understand how adolescents function within their romantic relationships to identify potential intervention points that can improve adolescents’ relationship skills. Adolescents frequently utilize technology within their relationships, with positive and negative implications. Thus, the digital context is an important area of research for adolescent romantic relationship functioning. The neo-ecological theory and the transformation framework help contextualize the digital context's impact on adolescent romantic relationships. The first study utilized two experiments to test the effects of an adolescent’s romantic partner hypothetically ”liking” a digital relationship threat’s Instagram post on their feelings of jealousy and digital dating abuse behaviors. Adolescents reported greater feelings of jealousy and engagement in digital dating abuse behaviors when their romantic partner “liked” a post from a different-gendered individual, and effects were exacerbated when that individual was high on attractiveness. While the digital context may serve as a risk context for adolescent relationships, the risk conferred may depend on the couple's functioning. Thus, the second study examined how sexting among adolescent couples was associated with their daily affect. Results demonstrate that while sexting may boost an adolescent’s affect on the same day, it is related to worse affect as the days pass. Lastly, the digital context can also be an external stressor that impacts the relationship. Thus, the third study examined how daily digital stress exposure during the COVID-19 pandemic is associated with late adolescent romantic couples’ substance use and mental health. This study examined actor and partner effects to assess the dyadic nature of stress contagion between romantic partners. This dissertation advances the current literature on associations between the digital context, adolescent development, and adolescent romantic relationship functioning.

Alcohol use remains a major public health concern and economic burden. Extant literature suggests that young adulthood is a particularly high-risk developmental period for heavy drinking. Given this, it is imperative to understand possible risk and protective factors for heavy drinking and related consequences during this risky developmental period. Prior research has shown that both drinking history and alcohol response (AR) are consistent predictors of future drinking outcomes. However, it is unclear how they may work together to confer this risk. The current study aimed to fill this gap in the literature by examining how alcohol use trajectories across adolescence and early adulthood impacted relations between AR after an alcohol challenge and drinking outcomes over a 2-year period in a sample of young adult moderate to heavy drinkers. Results showed that both drinking history and AR were independently predictive of alcohol outcomes at the 6-month follow-up such that a more extensive drinking history, greater high arousal positive effects, and lesser low arousal negative effects predicted greater drinking and alcohol-related problems 6-months later. However, drinking history and AR were largely not predictive of change in drinking outcomes over time. Finally, AR did not mediate the relationship between drinking history and later alcohol-related outcomes. This is the first study to address relations among drinking history, AR, and later drinking outcomes using a longitudinal alcohol challenge design with a full account of early drinking history. Future research would benefit from inclusion of a broad range of drinkers and longer follow-up assessments to better understand the complex pathways of risk from early drinking history and AR to future drinking outcomes. Such efforts may increase the understanding of who is at greatest risk and/or would benefit most from specific intervention programs.