Cognitive Processes Shaping Individual and Collective Belief Systems


Vlasceanu, M. (2021). Cognitive Processes Shaping Individual and Collective Belief Systems. Psychology and Neuroscience . Princeton University.
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Misinformation spread is among the top threats facing the world today. In my dissertation I strive to provide a deeper understanding of the socio-cognitive factors that can impact beliefs and of the potential for translating and implementing this understanding into policies aimed at reducing misinformation at a societal level. In the first Part, I introduce a theoretical generative framework for investigating factors influencing beliefs (Chapter 1). I then provide empirical support for this framework (N=7068) at the individual (Part 2, Chapters 2-5) and collective (Part 3, Chapters 6-8) levels of investigation. Finally, in Part 4 I suggest applications and future trajectories (Chapter 9). Starting with the individual level of investigation, in a series of online and lab experimental studies I show how psychological processes such as memory accessibility (Chapter 2), emotional arousal (Chapter 3), predictions errors (Chapter 4), and social norms (Chapter 5) can be leveraged to change people’s beliefs. For instance, in a series of laboratory experiments, I find that strengthening the memory of a statement increases its believability, while weakening its memory in a targeted fashion decreases its believability (Chapter 2). Given the interdependence between memory and emotions, in a series of online experiments, I also show that pairing emotionally arousing images with statements subsequently increases the believability of these statements compared to statements that had been associated with neutral or no images (Chapter 3). In another series of online experiments I explore the effect of prediction errors on belief update. I find that people update their beliefs as a function of the size of the errors they make when evaluating relevant evidence, and that making large errors leads to more belief update than not engaging in prediction, while controlling for the evidence available. Importantly, I find that these effects hold across ideological boundaries (Democrats and Republicans, evaluating Neutral, Democratic, and Republican beliefs; Chapter 4). In the last series of experiments at the individual level, I show that people change their beliefs more in line with evidence portrayed as normative (e.g., shared by many on social media platforms) compared to evidence portrayed as non-normative (Chapter 5.1) and that normativity cues signaled by large groups of people are the most effective at changing beliefs (Chapter 5.2). While the studies outlined in Part 2 focus on investigating phenomena at an individual level, extensive research shows that such cognitive processes are highly sensitive to the social context in which they manifest. Therefore, in Part 3, at the collective level of investigation, I uncover how macro-level societal outcomes can emerge from micro-level psychological processes. I first show how conversational interactions trigger belief change at a dyadic level, as individuals talking to one another change their beliefs to match those of their conversational partners (Chapter 6). Then, I find that collective level outcomes (i.e., collective beliefs) are influenced by both the conversational network structure that characterizes the community (Chapter 7) as well as by individual level mechanisms (Chapter 8). Finally, in Part 4 (Chapter 9) I propose future avenues of investigation, such as evaluating the connections between beliefs and behaviors, focusing on translating these controlled experimental strategies into applied settings. The goal of this translational work is to encourage a more active use of science in everyday life, for example, in developing actionable recommendations for policy makers and communicators to dispel misinformation at a societal level.

Publisher's Version

Last updated on 07/27/2021