Is the plausibility account of the illusion of truth effect plausible?

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Yoojin Chang (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site:
Peter Delaney

Abstract: Repeated statements are more likely to be judged as true compared to statements that have not been repeated. This phenomenon in known as the Illusion of Truth effect. The most studied theory is that fluency induced by repetition gives an illusion that otherwise ambiguous statements are truthful. The two experiments in this dissertation tested the possibility that fluency might be supplemented by information about plausibility – that is, the presence or absence of relevant information in memory. The main dependent variable for the experiments was truth-confidence rating, which was a composite of the truth value and the confidence level for each rating reaction time. Various measures and manipulations of fluency (e.g., clarity, number of propositions, repetition) and plausibility (e.g., proposition plausibility, content valence) were included. Experiment 1 showed that despite repeated exposure of similar lexical features, contents that contradicted the target statement decreased truth-confidence ratings. Experiment 2 showed that the minimum plausibility rating of the propositions was a better predictor of veracity judgments compared to any of the reaction time measures. The results suggest that plausibility could be an important contributing factor in the Illusion of Truth effect, and possibly other related effects as well.

Additional Information

Language: English
Date: 2019
Fluency, Illusion of Truth Effect, Plausibility, Truth Judgments
Truthfulness and falsehood
Human information processing
Cognitive psychology

Email this document to