Political Polarization: the Result of Information Cascades?
When we have examined information cascades, it has generally been in the context of hypothetical bets involving urns or arbitrary “good” and “bad” states of the world. The concept, however, can also be applied more specifically to the recent phenomenon of political polarization. While it is commonly argued that political polarization occurs as a result of having “push[ed] people’s opinions to extremes,” researchers at the University of Michigan, Ann Arbor suggest that it may instead be the case that the very social networks and connections within which people are situated are fundamentally reorganized along political boundaries. This theory, if correct, would actually fall in line with other recent findings that indicate that political polarization is not actually creating more extremist views but rather greater separation between political cliques.
As a general definition, information cascades occurs when individuals observe the actions of other people and mimic them. This social phenomenon allows “the actions of a few individuals to quickly propagate through a social network.” In the digital sphere, these actions can take the form of seeing and sharing media items. When users are unhappy with others, they can simply take the action of blocking/unfollowing them to reorganize their social networks.
After having run simulations of individuals interacting with each other and political sources and being influenced by the behaviors of others, the researchers found rather conclusive evidence. Their findings indicate that indeed “information cascades cause social networks to become increasingly politically sorted as the information ecosystem becomes less correlated.” When news sources place differing amounts of emphasis on certain stories, individuals feel inclined to dissociate from each other. 
Individuals are not aware of each others’ political alignments yet still self-segregate when they notice certain individuals not behaving similarly to the mass. Each individual person watches the behaviors of their social neighbors and breaks ties with them when they act differently. Following extremely polarizing news sources ensure that one’s social neighbors behave identically nearly 100% of the time.
This sort of behavior is likely what is causing the digital political rift. The researchers’ findings, for instance, point towards the fact that more diverse and varied news coverage by a specific news source ensures healthy mixing and decreased tendencies towards the development of an echo chamber. If we are to ensure a healthy future for the digital and political ecosystem, it is imperative that the breakage of these digital information cascades be further examined for possible solutions.
Source:
Tokita, Christopher K., Andrew M. Guess, and Corina E. Tarnita. “Polarized Information Ecosystems Can Reorganize Social Networks via Information Cascades.” Proceedings of the National Academy of Sciences 118, no. 50 (December 14, 2021): e2102147118. https://doi.org/10.1073/pnas.2102147118.