Social networking and mental health: looking beyond frequency of use and towards mechanisms of action
Venue: Neuropsychopharmacology
Year: 2020

Social networking sites have become ubiquitous in daily life. A recent estimate of monthly active Facebook users alone is over 2.4 billion. While social media platforms can be used to seek peer support and may provide a greater sense of community, social media use has increasingly also been evoked as a possible explanation for the dramatic rise in mental illness and suicide observed in younger cohorts  In line with this notion, studies examining the association between social networking site usage, mental health outcomes (e.g. depression, anxiety, loneliness) and problematic health behaviors (e.g. substance use) have grown exponentially over the past few years (for a meta analysis, see  Yet despite strong hypotheses, actual effect size estimates of the association between social media use and mental health symptoms are small in magnitude and unreliable  One key explanation for these mixed findings lies in the inconsistent ways studies operationalize social media use. Often the focus is simply on frequency or duration of use rather than types of, or motivations for use. For example, whereas passive use (e.g. passively viewing) may be associated with worse psychiatric symptoms, other types of use (e.g. posting or commenting) may be associated with improved well being and civic engagement  Research on this topic is further limited by a lack of prospective and experimental studies. While social media usage may increase depression and anxiety symptoms, it is equally plausible that worsening depression or anxiety leads to an increase in passive social media use. Longitudinal research is furthermore lacking that could help clarify potential developmental or cohort differences in causality; associations between types of use and mental health outcomes may differ between older and younger adults using social networking sites  The preponderance of cross sectional studies presents a particular challenge in identifying potential mechanisms linking social media use and mental health symptoms. In one of the few experimental studies, students who took a 1 week break from Facebook experienced improved well being and increases in positive mood, compared with those with continued Facebook usage. These effects were especially pronounced for those with heavy or passive usage, and those who endorsed envy while viewing posts  What remains less clear is exactly how passive or heavy use contributes to increased negative mood, and whether that effect is specific. The lack of studies focused on mechanisms consequently means that the field lacks a comprehensive theoretical model to explain the current mixed findings. Given the exponential growth of social networking sites and preliminary evidence that some forms of social media use may cause or worsen psychopathology, a strategic program of research moving forward is needed. First, future studies should go beyond merely assessing frequency or duration of social media use and instead more carefully characterize basic types of use, motivations for use (e.g. loneliness) or identify different patterns of engagement with social networking sites. Objective measures of use should be prioritized over self report. Technological software advances (e.g. passive data collection apps and algorithms) will aid in more accurate and less biased measures of use, and similarly, advances in machine learning and natural language processing will further help researchers catalyze their investigations on the link between social media use and mental health outcomes. A second call to action for the field is to increase the number of experimental studies that test potential mechanisms. To date, only a handful of studies have considered potential factors that could help explain an association between worse mental health outcomes and use of social networking sites. One notable exception is cross sectional research focused on "fear of missing out" (FOMO) with results indicating FOMO may mediate the relationship between more frequent and problematic smartphone use and anxiety, specifically [5] However, no experimental studies have examined this mediational model, raising questions about the proposed causality. There are furthermore numerous additional pathways that have only received marginal attention. For example, social media use may (or may not) have a direct impact on declines in face to face social interactions, which when combined with more passive use may impact levels of belongingness and subsequent downstream effects on mood. Social media use could also contribute to increased reliance on maladaptive coping strategies, such as distraction, avoidance, and suppression, while simultaneously hindering the use of more adaptive behaviors. A range of cognitive (e.g. self efficacy) behavioral (e.g. substance use) and emotional (e.g. loneliness, sustained negative affect) factors could act as additional mediators of these relationships. The impact on or moderating role of executive function, including attention and decision making, may further present a promising line of inquiry. Research should also examine the specific effects of social comparison and social shaming, particularly with respect to gender differences, and how they may lay a foundation for cyber bullying (see  for a review) Health behaviors, such as increased sedentariness, interrupted sleep, and substance use should also be investigated, along with differential effects across gender. In addition to individual difference factors, researchers may also want to consider more group level vulnerabilities, including the sharing of misinformation, which could have direct impacts on increasing