Scrolling to wisdom: the impact of social media news exposure on knowledge perception

The present study explores the effect of exposure to news in a social media environment on people’s perceived knowledge and on the “Illusion of knowledge” —that is, the overestimation of perceived knowledge relative to actual knowledge. Using a mixed, within-subjects design, participants (N = 828) engaged in a two-session study featuring pre- and post-exposure assessments. Participants scrolled through a social media newsfeed and completed assessments of perceived and actual knowledge. We hypothesized that (1) social media exposure would increase perceived knowledge, (2) this increase would not align with actual knowledge, and (3) higher topic involvement would exacerbate these effects. While most of the preregistered hypotheses did not receive clear statistical support, some effects were consistent with our predictions. Perceived knowledge increased over time, suggesting a general exposure effect; however, differences between exposed and non-exposed topics were not statistically significant, possibly due to test effects or limited engagement with the platform. A strong illusion of knowledge was observed across topics, suggesting robust overestimation. This high baseline may have created a ceiling that constrained the detection of exposure effects. This study was conducted as a Registered Report (https://doi.org/10.24072/pci.rr.100986), accepted in principle prior to data collection. To our knowledge, it represents one of the most ecologically valid attempts in the literature to simulate social media exposure in an experimental setting.