Is it all about the feeling? Affective and (meta-)cognitive mechanisms underlying the truth effect

The face of illusory truth: Repetition of information elicits affective facial reactions predicting judgments of truth

People tend to judge repeated information as more likely true compared with new information. A key explanation for this phenomenon, called the illusory truth effect, is that repeated information can be processed more fluently, causing it to appear more familiar and trustworthy. To consider the function of time in investigating its underlying cognitive and affective mechanisms, our design comprised two retention intervals. Seventy-five participants rated the truth of new and repeated statements 10 min, as well as 1 week after first exposure while spontaneous facial expressions were assessed via electromyography. Our data demonstrate that repetition results not only in an increased probability of judging information as true (illusory truth effect) but also in specific facial reactions indicating increased positive affect, reduced mental effort, and increased familiarity (i.e., relaxations of musculus corrugator supercilii and frontalis) during the evaluation of information. The results moreover highlight the relevance of time: both the repetition-induced truth effect as well as EMG activities, indicating increased positive affect and reduced mental effort, decrease significantly after a longer interval.

Insight in the Conspiracist's Mind

Academic AbstractThe motto of the conspiracist, "Do your own research," may seem ludicrous to scientists. Indeed, it is often dismissed as a mere rhetorical device that conspiracists use to give themselves the semblance of science. In this perspective paper, we explore the information-seeking activities ("research") that conspiracists do engage in. Drawing on the experimental psychology of aha experiences, we explain how these activities, as well as the epistemic experiences that precede (curiosity) or follow (insight or "aha" experiences) them, may play a crucial role in the appeal and development of conspiracy beliefs. Aha moments have properties that can be exploited by conspiracy theories, such as the potential for false but seemingly grounded conclusions. Finally, we hypothesize that the need for autonomous epistemic agency and discovery is universal but increases as people experience more uncertainty and/or feel epistemically excluded in society, hence linking it to existing literature on explaining conspiracy theories.

More familiar, more credible? Distinguishing two types of familiarity on the truth effect using the drift-diffusion model

Familiar information is more likely to be accepted as true. This illusory truth effect has a tremendous negative impact on misinformation intervention. Previous studies focused on the familiarity from repeated exposure in the laboratory, ignoring preexisting familiarity with real-world misinformation. Over three studies (total N = 337), we investigated the cognitive mechanisms behind the truth biases from these two familiarity sources, and whether fact-checking can curb such biased truth perceptions. Studies 1 and 2 found robust truth effects induced by two sources of familiarity but with different cognitive processes. According to the cognitive process model, repetition-induced familiarity reduced decision prudence. Preexisting familiarity instead enhanced truth-congruent evidence accumulation. Study 3 showed that pre-exposing statements with warning flags eliminated the bias to truth induced by repetition but not that from preexisting familiarity. These repeated statements with warning labels also reduced decision caution. These findings furthered the understanding of how different sources of familiarity affect truth perceptions and undermine the intervention through different cognitive processes.

The illusory certainty: Information repetition and impressions of truth enhance subjective confidence in validity judgments independently of the factual truth

People not only judge repeatedly perceived information as more likely being true (the so-called truth effect) they also tend to be more confident after judging the validity of repeated information. These phenomena are assumed to be caused by a higher subjective feeling of ease (i.e., fluency) when processing repeated (vs. new) information. Based on the suggestion that a higher number of coherent mental activations is promoting a fluency experience, we argue that besides repetition an already existing information network, that is (nonspecific) prior knowledge, can enhance fluency. Following this argumentation, information repetition as well as the act of judging incoming information as being true (vs. false) should feed into subjective confidence - independently of the factual truth (when judging under uncertainty). To test this, we reanalyzed two published data sets and conducted a new study. In total, participants (N = 247) gave 29,490 truth judgments and corresponding ratings of subjective confidence while attending two judgement phases (i.e., 10 min and 1 week after the exposure phase in each experiment). Results showed that (a) repetition (in 3 of 3 data sets) and (b) impressions of truth (in 2 of 3 data sets) were systematically related to higher subjective confidence. Moreover, we found (c) a significant positive interaction between repetition and impressions of truth after both intervals in all data sets. Our analyses further underline the moderating effect of time: Influences of repetition significantly decreased with increasing time interval. Notably, the factual truth did not systematically affect any of the above reported effects.

The Role of Valence Matching in the Truth-by-Repetition Effect

People judge repeated information as truer than new information, a “truth-by-repetition” effect. Because repetition increases processing fluency, which is assumed to elicit positive affect, participants may match their positive experience associated with repeated information with a positive (“true”) rather than negative (“false”) response. We tested this valence-matching hypothesis in a preregistered experiment by manipulating the affective congruency of the response format. Specifically, in the congruent condition, participants had to select a positive (negative) picture to respond “true” (“false”). In the incongruent condition, we reversed these associations. In line with the valence matching hypothesis, the truth-by-repetition effect was larger in the congruent than incongruent condition. However, the effect was small, and Bayesian analyses were inconclusive. In addition, the truth-by-repetition effect was significant in both response format conditions. The results suggest a possible contribution of a valence matching process to the truth-by-repetition effect, but one that does not challenge extant models.