A recent study published in the journal PLOS ONE by researchers from USC and Australia explored the impact of repetition on people’s beliefs, specifically regarding climate science. The study found that even strong believers in climate science were more likely to perceive skeptical and pro-climate beliefs as true when they encountered them a second time. This phenomenon, known as the “illusory truth effect,” highlights how the repetition of information, whether true or false, can influence individuals’ perceptions of reality.
The researchers conducted two rounds of studies with participants who were mainly believers in climate science. In both studies, participants were asked to rate the truth of statements related to climate skepticism, support for climate science, and weather-related filler statements. After a 15-minute interval, they were presented with another set of claims, half of which repeated the earlier statements. The participants then rated these claims on a six-point scale and indicated whether they seemed scientific or climate-skeptical.
Despite their strong beliefs in climate science, the majority of participants, including those categorized as the most concerned (“alarmed”) about climate change, considered all claims, including those opposing their beliefs, more valid when repeated. This finding suggests that even a single repetition of information can impact individuals’ perceptions of truth. The lead author of the study, Mary Jiang, emphasized that this increase in belief due to repetition occurred even among strong endorsers of climate science, highlighting the powerful influence of repetition on beliefs.
The study’s findings underscore the importance of being cautious about the repetition of information, especially when it comes to false claims. While amplifying truthful messages can reinforce positive actions, the repetition of falsehoods can be harmful. The researchers suggest that instead of repeating false information, efforts should focus on reinforcing truths to make them more familiar and likely to be believed. This study highlights the need for individuals to critically evaluate information they encounter and be mindful of the impact of repetition on their beliefs.
The researchers worked with two groups of participants, with almost all of them endorsing climate science beliefs, indicating their strong belief in humans’ responsibility for climate change. The participants were categorized into different levels of concern about climate change, ranging from those who acknowledge it as a problem but take little action to those who are deeply alarmed about the issue. Despite their differing levels of concern, all participants, including the strongest believers, were influenced by the repetition of statements, demonstrating the pervasive effect of repetition on beliefs.
The study’s co-author Norbert Schwarz, a psychology professor at USC, expressed concern about the impact of repetition on people’s beliefs, particularly in the context of climate science where accurate information is crucial for informed decision-making. The findings of the study highlight the need for vigilance in consuming and sharing information, as repetition can blur individuals’ sense of truth and influence their beliefs. By being mindful of the power of repetition and actively seeking out truthful information, individuals can better navigate the complexities of information dissemination and make informed choices that align with reality. The study emphasizes the importance of reinforcing truthful messages to counteract the potentially harmful effects of repeated falsehoods on people’s beliefs and decision-making processes.
