The illusory truth effect: A review of how repetition increases belief in misinformation

Illusory truth effect across languages and scripts

The repetition of a statement increases its credibility, a phenomenon known as the illusory truth effect. Here we tested whether the illusory truth effect persists across languages and scripts. In two experiments, Italian-English (n = 80) and Greek-English (n = 66), unbalanced bilinguals were exposed to 60 written unknown trivia statements in English. After a distractor math task, participants rated the truthfulness of the same 60 (repeated) statements and 60 new statements, which were presented either in the same language as in the exposure phase (English) or in a different language (Italian, Experiment 1, or Greek, Experiment 2). Response times were faster when information was repeated in the same language compared to a different language, suggesting increased processing fluency in the former than in the latter case. Truth ratings yielded an illusory truth effect: repeated statements were considered more truthful than new statements. Interestingly, the magnitude of the illusory truth effect remained regardless of whether the repetition was in the same or in a different language and persisted even when the different language condition also entailed a different script (Latin in exposure phase and Greek in repetition). The results suggest that the language of information presentation is not a critical factor to affect the illusory truth effect, despite the fact that repetition in the same language increases processing speed. We interpret our results in light of the referential theory (Unkelbach & Rom, Cognition 160: 110-126, 2017), attributing the illusory truth effect to conceptual fluency induced by the overlap of activated conceptual representations in bilingual memory.

The illusory-truth effect and its absence under accuracy-focused processing are robust across contexts of low and high advertising exposure

In present-day digital environments, people frequently encounter content from sources of questionable trustworthiness. Advertising is an untrustworthy source because its purpose is to persuade consumers rather than to provide impartial information. One factor known to enhance the perceived truth of advertising claims is repetition: Repeated advertising claims receive higher truth ratings than novel advertising claims. The phenomenon that repetition enhances processing fluency which enhances truth judgments is known as the illusory-truth effect. Does repetition always enhance truth judgments? For instance, does repetition enhance truth judgments even in contexts with extensive advertising exposure in which enhanced processing fluency could be used to classify a statement as likely coming from an untrustworthy source? In two experiments, we examined the illusory-truth effect by presenting participants with product statements in an exposure phase and collecting truth judgments for both repeated and new statements in a test phase. In a low-advertising-exposure condition, most of the statements were labeled as scientific studies while in the high-advertising-exposure condition, most of the statements were labeled as advertising. When participants read the product statements in the exposure phase, a typical illusory-truth effect was obtained: In the test phase, repeated statements received higher truth ratings than new statements. However, when participants were instructed to adopt an accuracy focus at encoding by judging the truth of the product statements, new statements were judged to be as true as repeated statements. Both the illusory-truth effect and its absence under accuracy-focus instructions were found to be robust across different levels of advertising exposure.

Repetition increases the perceived truth of inferred statements: evidence from transitive relations and non-transitive relations

The illusory truth effect refers to the phenomenon where repeated statements are more likely to be perceived as true compared to new statements. This effect encompasses not only verbatim repetition but also statements that are implied or inferred from the original. The illusory truth effect can be explained by the referential theory of truth, which posits that when processing a repeated statement, the previously formed coherent network will prompt individuals to judge it as true. Currently, the referential theory of truth still lacks evidence involving contexts with multiple statements. Our study investigates, across three experiments, whether statements inferred from multiple statements are perceived to be more true than new statements. Experiment 1a and 1b tested whether statements derived from transitive inference are judged more truthful. Experiment 2 used materials with non-transitive relations to see if erroneous inferred statements are also seen as more truthful. The results showed that, compared to new statements, statements inferred from the original statements with transitive relations are considered more truthful. More importantly, even when no transitive relations existed between the original statements, individuals still tend to perceive the erroneous inferred statements as more truthful compared to new statements. Our study provides new evidence for the referential theory of truth and highlights the role of inferential relations in establishing semantic network coherence. These findings further highlight the significant impact of the illusory truth effect in real-life situations.

Quantifying Public Engagement With Science and Malinformation on COVID-19 Vaccines: Cross-Sectional Study

BACKGROUND

Medical journals are critical vanguards of research, and previous years have seen increasing public interest in and engagement with medicoscientific findings. How findings propagate and are understood and what harms erroneous claims might cause to public health remain unclear, especially on publicly contentious topics like COVID-19 vaccines. Gauging the engagement of the public with medical science and quantifying propagation patterns of medicoscientific papers are thus important undertakings. In contrast to misinformation and disinformation, which pivot on falsehood, the more nuanced issue of malinformation, where ostensibly true information is presented out of context or selectively curated to cause harm and misconception, has been less researched. As findings and facts can be selectively marshaled to present a misleading picture, it is crucial to consider this issue and its potential ramifications.

OBJECTIVE

This study aims to quantify patterns of public engagement with medical research and the vectors of propagation taken by a high-profile incidence of medical malinformation.

METHODS

In this work, we undertook an analysis of all altmetric engagements over a decade for 5 leading general-purpose medical journals, constituting approximately 9.8 million engagements with 84,529 papers. We identify and examine the proliferation of sentiment concerning a high-profile publication containing vaccine-negative malinformation. Engagement with this paper, with the highest altmetric score of any paper in an academic journal ever released, was tracked across media outlets worldwide and in social media users on Twitter (subsequently rebranded as X). Vectoring media sources were analyzed, and manual sentiment analysis on high-engagement Twitter shares of the paper was undertaken, contrasted with users' prior vaccine sentiment.

RESULTS

Results of this analysis suggested that this COVID-19 scientific malinformation was much more likely to be engaged and amplified with negative by vaccine-negative Twitter accounts than neutral ones (odds ratio 58.2, 95% CI 9.7-658.0; P<.001), often alluding to the ostensible prestige of medical journals. Malinformation was frequently invoked by conspiracy theory websites and non-news sources (71/181 citations, 39.2%) on the internet to cast doubt on the efficacy of vaccination, many of whom tended to cite the paper repeatedly (51/181, 28.2%).

CONCLUSIONS

Our findings suggest growing public interest in medical science and present evidence that medical and scientific journals need to be aware of not only the potential overt misinformation but also the more insidious impact of malinformation. Also, we discuss how journals and scientific communicators can reduce the influence of malinformation on public understanding.

Susceptibility to online misinformation: A systematic meta-analysis of demographic and psychological factors

Nearly five billion people use and receive news through social media and there is widespread concern about the negative consequences of misinformation on social media (e.g., election interference, vaccine hesitancy). Despite a burgeoning body of research on misinformation, it remains largely unclear who is susceptible to misinformation and why. To address this, we conducted a systematic individual participant data meta-analysis covering 256,337 unique choices made by 11,561 US-based participants across 31 experiments. Our meta-analysis reveals the impact of key demographic and psychological factors on online misinformation veracity judgments. We also disentangle the ability to discern between true and false news (discrimination ability) from response bias, that is, the tendency to label news as either true (true-news bias) or false (false-news bias). Across all studies, participants were well above-chance accurate for both true (68.51%) and false (67.24%) news headlines. We find that older age, higher analytical thinking skills, and identifying as a Democrat are associated with higher discrimination ability. Additionally, older age and higher analytical thinking skills are associated with a false-news bias (caution). In contrast, ideological congruency (alignment of participants' ideology with news), motivated reflection (higher analytical thinking skills being associated with a greater congruency effect), and self-reported familiarity with news are associated with a true-news bias (naïvety). We also find that experiments on MTurk show higher discrimination ability than those on Lucid. Displaying sources alongside news headlines is associated with improved discrimination ability, with Republicans benefiting more from source display. Our results provide critical insights that can help inform the design of targeted interventions.

Determinants of multimodal fake review generation in China's E-commerce platforms

This paper develops a theoretical model of determinants influencing multimodal fake review generation using the theories of signaling, actor-network, motivation, and human-environment interaction hypothesis. Applying survey data from users of China's three leading E-commerce platforms (Taobao, Jingdong, and Pinduoduo), we adopt structural equation modeling, machine learning technique, and Bayesian complex networks analysis to perform factor identification, path analysis, feature factor importance ranking, regime division, and network centrality analysis of full sample, male sample, and female sample to reach the following conclusions: (1) platforms' multimodal recognition and governance capabilities exert significant negative moderating effects on merchants' information behavior, while it shows no apparent moderating effect on users' information behavior; users' emotional venting, perceived value, reward mechanisms, and subjective norms positively influence multimodal fake review generation through perceptual behavior control; (2) feature factors of multimodal fake review generation can be divided into four regimes, i.e., regime 1 includes reward mechanisms and perceived social costs, indicating they are key feature factors of multimodal fake review generation; merchant perception impact is positioned in regime 2, signifying its pivotal role in multimodal fake review generation; regime 3 includes multimodal recognition and governance capabilities, supporting/disparaging merchants, and emotional venting; whereas user perception impact is positioned in regime 4, indicating its weaker influence on multimodal fake review generation; (3) both in full sample, male sample, and female sample, reward mechanisms play a crucial role in multimodal fake review generation; perceived value, hiring review control agency, multimodal recognition and governance capabilities exhibit a high degree of correlation; however, results of network centrality analysis also exhibit heterogeneity between male and female samples, i.e., male sample has different trends in closeness centrality values and betweenness centrality values than female sample. This indicates that determinants influencing multimodal fake review generation are complex and interconnected.