Between Fact and Fiction: Media Effects on Misperceptions Over Time

Abstract

During the past decade, worries about a “post-truth” era have raised urgent questions about how media shape what people believe to be true. This dissertation investigates when, how, and for whom media use fosters misperceptions—false yet confidently held beliefs—across a range of issues. It combines a large four-wave panel survey from Sweden (N = 3,530) with panel modeling to trace change over time and to separate media effects from stable, trait-like differences between people. The work proceeds in four parts: a systematic literature review of more than ten years of research on misinformation, disinformation, and fake news maps the field and pinpoints a lack of longitudinal evidence; three empirical studies then test media effects, selection effects, and the roles of ideology and media trust in these processes. Overall, people became slightly less misinformed over the period studied—a trajectory that appears largely unaffected by media use. With one exception: right-wing alternative media use consistently slowed the decline, although the effects are small. Right-wing alternative media users also showed higher levels of misperceptions to begin with, pointing to the harmful potential of such outlets for public debate. Shifts in misperceptions did not, however, drive subsequent media choices for any type of media use. Ideological leaning mattered for levels of misinformedness—right-leaning respondents were, on average, more misinformed—but not for growth trajectories. Perhaps most importantly, media trust emerged as decisive for change: when trust fell, the decline in misperceptions stalled, or even reversed. Right-wing alternative media use further accelerated the trust decline, slowing the reduction of misperceptions via diminished trust. Together, these results caution against alarmist accounts of a “post-truth” era and an increasingly misinformed citizenry. Yet the findings also showcase the harmful potential of right-wing alternative media for citizen competence, both in terms of undermining media trust and sustaining misperceptions. Finally, a crucial pathway to resilience emerges: safeguarding trust may be as important as countering misinformation itself.