Time-trajectories of depression, social anxiety, and social functioning throughout college

College matriculation is a major life transition. Most students enter college during young adulthood, a critical development period for social and mental health. Students who enter college with mental health challenges may struggle to connect with peers and capitalize on abundant social opportunities. In particular, social anxiety and depression symptoms may alter longer-term trajectories of students’ social functioning (namely social support and time spent socializing) throughout college. To examine the prospective relationships between these mental health symptoms and social functioning, we conducted a longitudinal study with undergraduates ( N = 323) who completed baseline surveys and 30-day daily diaries each year of college. Using multilevel growth curve models, we tested separate forward- and reverse-direction effects to assess changes in symptom–functioning relationships over time. Results indicated that higher social anxiety symptoms predicted a steeper decline in time spent socializing, but not in perceived social support. Depression symptoms did not predict changes in social functioning trajectories; however, greater perceived social support was associated with fewer depression symptoms on average. These findings suggest that social anxiety symptoms may increase risk for social isolation, which could, in turn, worsen mental health outcomes. Moreover, our results provide support for the stress-buffering hypothesis and suggest that social support may help mitigate mild depression symptoms.