Cognitive Contagion: How to model (and potentially counter) the spread of fake news

Rabb, Nicholas; Cowen, Lenore; Ruiter, Jan P. de; Scheutz, Matthias

Understanding the spread of false or dangerous beliefs - so-called mis/disinformation - through a population has never seemed so urgent to many. Network science researchers have often taken a page from epidemiologists, and modeled the spread of false beliefs as similar to how a disease spreads through a social network. However, absent from those disease-inspired models is an internal model of an individual's set of current beliefs, where cognitive science has increasingly documented how the interaction between mental models and incoming messages seems to be crucially important for their adoption or rejection. We introduce a cognitive contagion model that combines a network science approach with an internal cognitive model of the individual agents, affecting what they believe, and what they pass on. We show that the model, even with a very discrete and simplistic belief function to capture cognitive dissonance, both adds expressive power over existing disease-based contagion models, and qualitatively demonstrates the appropriate belief update phenomena at the individual level. Moreover, we situate our cognitive contagion model in a larger public opinion diffusion model, which attempts to capture the role of institutions or media sources in belief diffusion - something that is often left out. We conduct an analysis of the POD model with our simple cognitive dissonance-sensitive update function across various graph topologies and institutional messaging patterns. We demonstrate that population-level aggregate outcomes of the model qualitatively match what has been reported in COVID misinformation public opinion polls. The overall model sets up a preliminary framework with which social science misinformation researchers and computational opinion diffusion modelers can join forces to understand, and hopefully learn how to best counter, the spread of misinformation and"alternative facts."