The Repetition Effect: How Frequent Exposure Makes False Claims Seem More Credible

In a groundbreaking discovery about human psychology, researchers have found that repeated exposure to false information makes it seem more believable to almost everyone—regardless of their critical thinking skills or skepticism toward conspiracy theories.

The study, conducted by researchers Bowes and Fazio, reveals that what psychologists call the “illusory truth effect” impacts individuals across the cognitive spectrum. Their research demonstrates that even people who typically question information and aren’t prone to conspiracy thinking become more likely to perceive false statements as truthful after repeated exposure.

“I study individual differences—so how people differ in ways that may reduce the influence of false information—but with the illusory truth effect, those differences don’t seem to matter,” Bowes explains. “If you’re more rational or prone to reflection, that doesn’t move the needle.”

This phenomenon has significant implications for our information ecosystem, where social media algorithms and news feeds often recirculate content, potentially amplifying falsehoods through repetition. The research suggests that traditional safeguards against misinformation—critical thinking skills and skepticism—may be less effective than previously thought.

While the effect has its limits, it can still shift perceptions in concerning ways. “It’s not like if you keep hearing that the Earth is a perfect square, you’ll start thinking it’s true,” Bowes clarifies. “But you will see it as slightly less implausible than you did before.”

This subtle shift in perception can have real-world consequences, particularly in areas like public health, politics, and science communication, where slight changes in believability can influence important decisions and public discourse.

The findings come at a critical time when misinformation and conspiracy theories have proliferated across digital platforms. Tech companies and policymakers have struggled to address the spread of false information, often focusing on fact-checking and media literacy as primary solutions. However, this research suggests such approaches may have limited effectiveness against the psychological mechanisms that make repetition so powerful.

Cognitive scientists have studied the illusory truth effect for decades, but Bowes and Fazio’s work is particularly noteworthy for examining individual differences in susceptibility. Previous theories suggested that certain personality traits or thinking styles might provide immunity to the effect, but the new research contradicts this reassuring notion.

Perhaps most troubling is the researchers’ conclusion about prevention strategies. “Unfortunately, knowing that the illusory truth effect exists doesn’t seem to offer much protection from it,” Bowes notes. Self-awareness about cognitive biases—often promoted as a defense against misinformation—appears ineffective against this particular vulnerability.

Instead, the researchers suggest that the only reliable protection is environmental: reducing exposure to false claims and conspiracy theories altogether. This recommendation has profound implications for how platforms might need to address harmful content, shifting focus from labeling falsehoods to preventing their circulation in the first place.

The research also raises questions about responsibility in information sharing. If simple exposure increases believability regardless of content quality or a person’s critical thinking skills, then controlling what gets amplified becomes crucial for maintaining a healthy information environment.

For individuals navigating today’s complex information landscape, the study offers a sobering reminder that our minds process information in ways that sometimes bypass our conscious control. Even the most diligent critical thinkers remain vulnerable to the subtle influence of repetition.

As social media companies, news organizations, and policymakers grapple with the challenges of misinformation, this research provides valuable insight: addressing the quantity of exposure to false information may be just as important as addressing its quality or providing tools to evaluate it.