False and misleading information is readily accessible in people's environments, oftentimes reaching people repeatedly. This repeated exposure can significantly affect people's beliefs about the world, as has been noted by scholars in political science, communication, and cognitive, developmental, and social psychology. In particular, repetition increases belief in false information, even when the misinformation contradicts prior knowledge. We review work across these disciplines, identifying factors that may heighten, diminish, or have no impact on these adverse effects of repetition on belief. Specifically, we organize our discussion around variations in what information is repeated, to whom the information is repeated, how people interact with this repetition, and how people's beliefs are measured. A key cross-disciplinary theme is that the most influential factor is how carefully or critically people process the false information. However, several open questions remain when comparing findings across different fields and approaches. We conclude by noting a need for more interdisciplinary work to help resolve these questions, as well as a need for more work in naturalistic settings so that we can better understand and combat the effects of repeated circulation of false and misleading information in society.

In our modern well-connected world, false information spreads quickly and is often repeated multiple times. From laboratory studies, we know that this repetition can be dangerous as repetition increases belief. However, it is unclear how repetition affects belief in real-world settings. Here we examine a larger number of repetitions (16), more realistic timing of the repetitions (across two weeks), and more naturalistic exposures (text messages). 435 participants recruited from mTurk were texted true and false trivia statements across 15 days before rating the accuracy of each statement. Statements were seen either 1, 2, 4, 8, or 16 times. We find clear evidence that repetition increases belief. Initial repetitions produced the largest increase in perceived truth, but belief continued to increase with additional repetitions. The results imply that repeated exposure to false information can be dangerous and that technology companies and policymakers should do more to prevent the spread of misinformation.

Fact-checkers want people to both read and remember their misinformation debunks. Retrieval practice is one way to increase memory, thus multiple-choice quizzes may be a useful tool for fact-checkers. We tested whether exposure to quizzes improved people’s accuracy ratings for fact-checked claims and their memory for specific information within a fact check. Across three experiments, 1551 US-based online participants viewed fact checks (either health- or politics-related) with or without a quiz. Overall, the fact checks were effective, and participants were more accurate in rating the claims after exposure. In addition, quizzes improved participants’ memory for the details of the fact checks, even 1 week later. However, that increased memory did not lead to more accurate beliefs. Participants’ accuracy ratings were similar in the quiz and no-quiz conditions. Multiple-choice quizzes can be a useful tool for increasing memory, but there is a disconnect between memory and belief.

Using incorrect worked examples during mathematics instruction can improve student learning. However, teachers worry that students may confuse correct and incorrect examples over time, and memory research supports this fear. To examine if this forgetting occurs, we had undergraduates rate the correctness of correct and incorrect worked examples immediately and one week later (Experiment 1). Previously studied incorrect examples were rated as slightly more correct after the delay, but this did not affect ratings of unstudied examples or problem-solving accuracy. In Experiment 2, we more closely mimicked how incorrect worked examples are used in classroom settings. Again, we found only small changes in students' memory for studied worked examples after the delay, and no changes for unstudied examples or problem-solving accuracy. Our findings suggest the costs of teaching with incorrect worked examples are limited to the specific studied problems, and do not affect learning of the underlying mathematical rule.

False and misleading information is readily accessible in people’s environments, oftentimes reaching people repeatedly. This repeated exposure can significantly affect people’s beliefs about the world, as has been noted by scholars in political science, communication, and cognitive, developmental, and social psychology. In particular, repetition increases belief in false information, even when the misinformation contradicts prior knowledge. We review work across these disciplines, identifying factors that may heighten, diminish, or have no impact on these adverse effects of repetition on belief. Specifically, we organize our discussion around variations in what information is repeated, to whom the information is repeated, how people interact with this repetition, and how people’s beliefs are measured. A key cross-disciplinary theme is that the most influential factor is how carefully or critically people process the false information. However, several open questions remain when comparing findings across different fields and approaches. We conclude by noting a need for more interdisciplinary work to help resolve these questions, as well as a need for more work in naturalistic settings so that we can better understand and combat the effects of repeated circulation of false and misleading information in society.