Summary
These can affect people differently based on age, education, or cognitive style, making awareness of these differences crucial for adequate media literacy. This is because they deliver the same claims repeatedly across feeds, ads, clips, and screenshots. Repetition → familiarity/fluency → “sounds true.”
Below are real, modern-world examples where repetition is documented to increase perceived truth (or sharing), plus a quick “how it shows up” for each, designed to spark your curiosity about how misinformation spreads.
1) Repeated “fake news” headlines on social media
What it looks like today: You see the same sensational headline multiple times (different accounts, exact wording, same screenshot).
Evidence: Experiments using actual fake-news-style headlines presented on Facebook found that even a single prior exposure increases perceived accuracy later—an illusory truth effect for fake news.
Why it matters: Even when claims were flagged as disputed, familiarity still boosted perceived accuracy in that research.
2) “Fact-check labels” don’t entirely stop the repetition’s effect
What it looks like today: A post gets a “disputed / context” label—but keeps circulating; people remember the claim, not the label.
Evidence: The same “prior exposure” work reports increased perceived accuracy even when the headlines were labeled as contested.
Why it matters: This aligns with broader findings that repetition increases truth judgments even for implausible statements.
3) COVID-19 “infodemic” patterns (repeated health misinformation)
What it looked like: The pandemic produced highly repeated claims across platforms and chat groups—some inaccurate, some dangerous.
Evidence: A 2023 Cognition paper shows that a single repetition can make people more likely to share misinformation, and that this happens because repetition raises perceived accuracy.
Related evidence: Research in Harvard Kennedy School Misinformation Review examined recall and perceived accuracy of COVID misinformation headlines, showing non-trivial uptake patterns during the pandemic information environment.
4) “I saw it everywhere, so it must be true” → increased sharing
What it looks like today: Someone shares a claim with “Not sure if true, but…”—because it feels familiar.
Evidence: The 2023 Cognition study directly ties repetition → higher perceived accuracy → higher sharing intent.
Evidence: The 2023 Cognition study directly ties repetition → higher perceived accuracy → higher sharing intent.
Why it matters: This explains why misinformation can spread even when people aren’t trying to deceive—the familiarity heuristic does the work.
5) Advertising: repeated product claims become “common knowledge.”
What it looks like today: “Clinically proven,” “boosts immunity,” “#1 recommended,” etc.—repeated across TV, podcasts, banners, influencers.
Evidence: A 2025 open-access paper explicitly tested advertising contexts and found repeated product statements were judged more trustworthy than new ones—the illusory truth effect operating in an advertising frame.
Important nuance: The same paper reports that an accuracy-focused instruction can reduce the effect, i.e., “pause and evaluate” helps.
“Even if you know better”: While awareness helps, research shows that even informed people can be influenced by repetition, so staying vigilant is an ongoing process for everyone.
What it looks like today: People who are generally informed still find themselves thinking a repeated claim is “maybe true.”
Evidence: Peer-reviewed research shows that prior knowledge doesn’t reliably protect against falsehoods: repeated falsehoods can receive higher truth ratings even when they contradict what participants already know.
7) Modern “cultural myths” that persist through repetition
Example: “We only use 10% of our brains.”
What it looks like today: Shows up in motivational content, pop science posts, movies—so it “feels true.”
Evidence: Psychology Today cites this as a classic example of the illusory truth effect, creating durable misconceptions through repetition.
8) Design & fluency tricks in modern media (not just repetition)
What it looks like today: Clean typography, simple phrasing, slick graphics, “explainer” aesthetics—content feels easy to process, so it feels more credible.
Evidence: Overviews of the effect emphasize that processing fluency drives perceived truth; even factors such as an easy-to-read presentation can raise truth judgments.
9) Modern fact-check ecosystems (example of repeated debunks)
What it looks like today: Fact-checkers maintain “myth hubs” because the same misconceptions recur.
Evidence: FactCheck.org’s COVID misconceptions index is explicitly organized to address recurring claims—illustrating how repetition keeps myths alive and demands ongoing correction.
A simple “modern-life” pattern to watch for
If you catch yourself thinking:
“I’ve heard that a lot… so it’s probably true.”
That’s the illusory truth effect in real time—familiarity masquerading as evidence.