Repetition of Misleading Information: “Illusory Truth” Effect

A Hassan, SJ Barber. Cogn Res Princ Implic. 2021 Dec; 6: 38. Open Access! The effects of repetition frequency on the illusory truth effect. doi: 10.1186/s41235-021-00301-5

“Repeated information is often perceived as more truthful than new information. This finding is known as the illusory truth effect, and it is typically thought to occur because repetition increases processing fluency…In Experiment 1, we showed participants trivia statements up to 9 times and in Experiment 2 statements were shown up to 27 times…In both experiments, we found that perceived truthfulness increased as the number of repetitions increased. However, these truth rating increases were logarithmic in shape. The largest increase in perceived truth came from encountering a statement for the second time, and beyond this were incrementally smaller increases in perceived truth for each additional repetition.”

My take (from authors): “Although believing repeated information to be true is evolutionarily efficient in a context where most of the information encountered is correct, it can be detrimental to believe information that is incorrect.”

Related blog posts:

Eklutna Lake, AK