Choosing to believe: How active sampling enhances the truth effect

Repeated exposure to information increases the credibility of this information, a well-studied phenomenon called the truth effect. While this phenomenon has been studied extensively by passively exposing people to preselected information pieces, in real-world contexts, people often sample information actively (e.g., by clicking on a headline on social media). In the present research, we propose and demonstrate in eight preregistered experiments (N = 953) that such active sampling of information increases the truth effect, leading to an enhanced belief in information one had initially been exposed to following one's active choice. We further test both stimulus-based explanations (i.e., people are more likely to sample information that is perceived to be more plausible) and processing-based explanations (i.e., sampling information boosts cognitive processes that also increase the truth effect), with evidence favoring the latter account. Overall, our findings imply that repeated exposure to information has a more profound influence on people's beliefs in settings where people actively choose which information they are exposed to. (PsycInfo Database Record (c) 2026 APA, all rights reserved).