The development of the project included a first group of experiments combining a robust paradigm from the Sociocognitive Psychology field that is profusely in the study of repetition and contradiction effects on truth assessment - the illusion of truth paradigm, with a robust paradigm from the Behavioural Economics field and which is the paradigm of choice to study trust and trustworthiness – the trust game. These experiments aimed at establishing the baseline of the paradigm and be sure that the implementation of different levels of source trustworthiness via the trust game was effective. However, the results of the experiments conducted in this cluster showed that the chosen manipulation of source trustworthiness was not successful (i.e. participants were not consistent their learning that a given player in the trust game was trustworthy or untrustworthy). This in turn led to the absence of effects of source trustworthiness on truth judgments of repeated and contradictory information. These results required an adaptation to the initial planned paradigm, which shaped the next cluster of experiments.
The second group of experiments involved the implementation of a different manipulation of source trustworthiness based on facial features. For that, avatar face pictures previously pre-tested as clearly inducing high and low levels of perceived trustworthiness were used. Two pilot studies showed that this new manipulation was effective, with information associated with avatar faces inducing high trustworthiness being judged more likely to be true than information associated with avatar faces inducing low trustworthiness. Three experiments testing the impact of source trustworthiness on repeated information, contradictory information, and on both repeated and contradictory information. Two additional pilot studies were conducted, in which trustworthiness-neutral avatar faces were added to the high and low trustworthiness faces to test if the effects of untrustworthy vs. trustworthy faces on truth judgments were due to trustworthy faces making information more believable or to untrustworthy faces making information less believable, compared to a trustworthiness-neutral baseline.
Finally, three additional studies were conducted. In extension studies 1 and 2, the information presented to participants in the experiments were more socially relevant than the general trivia statements presented in the previous studies – they were claims about nutrition and healthy dietary habits– to test the boundaries of effects found previously with a topic about which participants may be more familiar with and may relate to more. These two studies involved a large effort in the pre-testing of the new experimental materials (i.e. the claims about nutrition). In extension study 3, the avatar faces used in the previous experiments could be Caucasian, Black, or Asian. The goal of this manipulation and of the studies that will follow this first baseline is to uncover cognitive processes and mechanisms that may help reduce the disadvantages associated with negative stereotypes and attitudes towards specific social groups.
Regarding dissemination and communication activities, these included four presentations in important international conferences in the field and one invited talk at the Host’s Research Centre. The researcher was also involved in teaching activities at the Host institution, where she was able to introduce topics related to the project scope to bachelor students and in that way disseminate scientific content aligned with the project goals.
To reach a wider audience, dissemination activities also included communication activities in the traditional media and social media activities, with participation in one science dissemination radio show and a science dissemination Instagram live event. Additionally, the Host’s research center where the researcher was integrated also prepared and disseminated several posts about the project on social media (e.g. on the research center’s Instagram profile). The project also established an online presence with a website to disseminate the general project goals and activities. Finally, the project was also part of the 2021 European Researchers’ Night.
Regarding exploitation of the project results, the research activities that were conducted were the foundation of novel research proposals. In total, the researcher submitted 3 individual research grant proposals and three collaborative research grant proposals, with one proposal being granted funding (the researcher is member of the research team and the supervisor is a co-PI).
