Researchers examined how repetition can significantly influence people’s beliefs.
A study focusing primarily on individuals who believe in climate science demonstrates how easily information—and misinformation—can distort perceptions of what is true. Repetition is all it takes.
Recent research published in the journal PLOS ONE by teams from USC and Australia delved into the strong impact that repetition has on people’s beliefs.
Through two rounds of research, they discovered that even the most committed climate science supporters—those labeled as “alarmed” believers—perceived both skeptical and pro-climate viewpoints as more credible after encountering them a second time.
Norbert Schwarz, a co-author of the study and provost professor of psychology at USC Dornsife College of Letters, Arts and Sciences and USC Marshall School of Business, noted, “Just a single repetition can lead someone to view a claim as true. This is indeed alarming, especially when considering how many individuals are exposed to both accurate and misleading information, leading them to share or be influenced by it, which could have implications for the planet.”
Truthiness
Psychological research indicates that individuals are more inclined to believe statements that align with their personal beliefs.
However, their perceptions can shift upon repeated exposure to certain statements. The more frequently these statements are encountered, the more plausible they appear. Psychologists often term this phenomenon “truthiness,” or more formally, the “illusory truth effect.”
The research team was curious about how staunch supporters of climate science would react when faced with climate-skeptical claims.
The researchers involved 52 participants in the first study and 120 in the second. Nearly all participants—aside from 10%—believed in and supported climate science, which points to human responsibility for climate change.
During both studies, participants were asked to evaluate the validity of various statements, including climate-skeptical ones, supporters of climate science, and neutral weather-related fillers. After a 15-minute break, they assessed a new set of claims, half of which were repeats from earlier. They rated these statements on a six-point scale from “definitely true” to “definitely false.”
In the second study, participants were also asked whether a claim seemed more scientific or climate-skeptical.
The majority of participants (90%) supported climate science, ranging from those who were “concerned” about climate change but took minimal action, to the “alarmed,” who exhibited the highest levels of concern. Less than 10% viewed climate change as a non-issue.
Regardless of how strongly they believed, climate science supporters found all claims—even those contradicting their views—more credible upon repetition. This trend held true even among the “alarmed” participants, the most fervent supporters of climate science.
Mary Jiang from The Australian National University, who led the study, stated, “Participants perceived climate skeptic claims as more trustworthy after they were repeated just once. Interestingly, this heightened belief due to repetition occurred even among those who strongly endorse climate science.”
Schwarz pointed out that the findings suggest a positive aspect of repeating messages that are truthful and encourage beneficial behaviors. However, repeating false messages can have detrimental effects.
To sum up, this study highlights a vital lesson: we should refrain from repeating misinformation. It’s essential to consistently share accurate information so it becomes familiar and, therefore, more likely to be accepted as truth,” Schwarz advised.
