[4] Researchers observed the illusory truth effect's impact even on participants who knew the correct answer to begin with but were persuaded to believe otherwise through the repetition of a falsehood, to "processing fluency".
The illusory truth effect plays a significant role in fields such as advertising, news media, political propaganda, and religious indoctrination.
[2][5] On three occasions, Lynn Hasher, David Goldstein, and Thomas Toppino presented the same group of college students with lists of sixty plausible statements, some of them true and some of them false.
[5] This assumption was challenged by the results of a 2015 study by Lisa K. Fazio, Nadia M. Brasier, B. Keith Payne, and Elizabeth J. Marsh.
Published in the Journal of Experimental Psychology; the study suggested that the effect can influence participants who actually knew the correct answer to begin with, but who were swayed to believe otherwise through the repetition of a falsehood.
After replicating these results in another experiment, Fazio and her team attributed this curious phenomenon to processing fluency, the facility with which people comprehend statements.
A 2011 study by Jason D. Ozubko and Jonathan Fugelsang built on this finding by demonstrating that, generally speaking, information retrieved from memory is "more fluent or familiar than when it was first learned" and thus produces an illusion of truth.
[11] A 1992 study by Ian Maynard Begg, Ann Anas, and Suzanne Farinacci suggested that a statement will seem true if the information seems familiar.
[6][5] In a 2014 study, Eryn J. Newman, Mevagh Sanson, Emily K. Miller, Adele Quigley-McBride, Jeffrey L. Foster, Daniel M. Bernstein, and Maryanne Garry asked participants to judge the truth of statements attributed to various people, some of whose names were easier to pronounce than others.