During the first period of the project, we reviewed the relevant literature on the topic in psychology, neuro-economy and cognitive sciences and wrote a review article describing these findings and proposing our theoretical model, the Identity-Based Model of Political Belief (Van Bavel & Pereira, 2018). According to our model, when approaching new information, people compute the value of belief or attitude as a function of competing goals: accuracy or fairness goals on the one hand, and social identity goals on the other hand. The value of belief or attitude is computed depending on the weight put on these different goals, which might vary across situations and people.
Building up on this model, we ran a series of experiments testing the main idea in the context of belief in fake news: We found that people were more likely to believe news about the value-upholding behavior of ingroup politicians and the value-undermining behavior of outgroup politicians, regardless of the specific value being upheld or undermined. This demonstrates the preponderance of political social identity over ideological values. I presented this work at various conferences and report it in a paper currently being revised for publication at a high-impact peer-reviewed academic journal.
In addition, in an extension of this model to support for punishment as a function of political identity, we ran another series of experiments testing the influence of political in-group bias in support for punishment judgments. In two behavioral studies, we found evidence of political in-group bias in support for punishment of US politicians. We designed, implemented ran a follow-up fMRI study examining the neural processes underlying these judgments. We are currently analysing the behavioral and neural data from this experiment.
During the second period of the project, we further extended our understanding of the neural processes underlying the effects of political identity on moral cognition. We conducted a new experiment, in a different political context (i.e. the Netherlands), in which we measured cardiovascular responses. By examining the physiological responses, we aimed at understanding the social identity threat proposes to underly the effects previously observed. The results were inconclusive, but trigger new questions to be answered in future work.
Overall, this project contributed to the literature in psychology and political sciences by advancing our theoretical empirical understanding of political belief. We provided evidence for identity-based biased political thinking. These findings were widely shared with peers and with the public, through multiple presentations at conferences, the organization of a symposium at the largest social psychology conference, multiple invited talks to academic and non-academic audiences, as well as multiple interviews with journalists.
