Abstract：
Social media is viewed to be a key contributor to worsening mental health in adolescents, as most recently reflected in a public health advisory by the US Surgeon General. We provide new evidence on the causal effects of social media on mental health of college students during the Covid-19 pandemic, exploiting unique, longitudinal data collected before the Covid-19 pandemic began and at two points during the pandemic. We find small insignificant effects of social media 4 months into the pandemic during a period of social distancing, but large statistically significant negative effects 18 months into the pandemic when colleges were mostly back to normal operations. Using rich data on substance use, exercise, sleep, stress, and social support, we find some evidence of substitution away from activities that better support mental health at later stages of the pandemic but not at early stages. We find that the negative effects of social media are mostly concentrated among socially-isolated students. Both social support and resilience protect students from the negative effects of social media use. Policy implications include regulating social media while also bolstering social support and resilience as important protective factors.
摘要：
社交媒体被认为是青少年心理健康恶化的关键因素，正如美国外科医生最近在公共卫生咨询中所反映的那样。我们提供了新的证据，证明社交媒体在新冠肺炎大流行期间对大学生心理健康的因果影响，利用独特的，Covid-19大流行开始前和大流行期间两点收集的纵向数据。我们发现社交媒体在大流行4个月后在社交距离时期产生了微不足道的影响，但在大流行18个月后，当大学大多恢复正常运营时，有很大的统计意义的负面影响。利用丰富的物质使用数据，锻炼,睡眠,压力，社会支持,我们发现一些证据表明，在大流行的后期，而不是在早期阶段，这些活动可以更好地支持心理健康。我们发现，社交媒体的负面影响主要集中在社会孤立的学生身上。社会支持和复原力都可以保护学生免受社交媒体使用的负面影响。政策含义包括监管社交媒体，同时还将社会支持和复原力作为重要的保护因素。
