The Effects of Repetition on Belief in Naturalistic Settings

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 harmful 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 2 weeks), and more naturalistic exposures (text messages). Four hundred thirty five U.S. 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 one, two, four, eight, 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. We introduce a simple computational model suggesting that current accounts are insufficient to explain this observed pattern and that additional theoretical assumptions (e.g., that initial repetitions are more strongly encoded) are required. Practically, the results imply that repeated exposure to false information during daily life can increase belief in that misinformation.