Health Behavior Disparities Along Party Lines and Associative Diffusion

Austin van Loon
Stanford University

A striking pattern that we see in Americans’ response to the coronavirus pandemic is the variation in response predictable by political party identification. Specifically, American Republicans are much less likely than American Democrats to engage in and endorse health behaviors that are at the time of writing recommended by the World Health Organization (Kushner Gadarian et al 2020). From the perspective of associative diffusion (Goldberg and Stein 2018), this division can be explained by a parsimonious set of initial conditions including animosity between the two political parties and the salient political leanings of sources of opinions concerning the pandemic. Here, I briefly describe polarization in response to the pandemic from the perspective of associative diffusion, contrast this perspective to an alternative explanation that revolves around the idea of “political echo chambers”, and offer interventions to mend the American divide suggested by the associative diffusion model.

Associative diffusion is the process through which both consensus in schematic representation of the world and behavioral differentiation simultaneously emerge from interactions between individuals (Goldberg and Stein 2018). In this model, individuals have preferences for certain behaviors, observe others’ behaviors from which they infer the associations between those behaviors, and accordingly update their behavioral preferences to reduce cognitive dissonance, caused by e.g. having high preference for two behaviors that are negatively associated in one’s mental model of the world. This perspective brings to light two important pre-conditions for the behavioral differentiation we observe at present.

The first pre-condition is animosity between the two major political parties, demonstrated by unprecedented levels of affective polarization among Americans (Iyengar et al 2019). If intergroup animosity is related to a perceived dissimilarity between the groups (van Loon et al under preparation), then we can infer that even before the pandemic, Americans generally viewed Democrats and Republicans as more distinct than they have in recent history. From the perspective of associative diffusion, this sets the stage for especially strong and persistent behavioral divides between the groups, since a perceived association between endorsement or rejection of a behavior and political identity would present strong psychic incentives for partisans to act in accordance with members of their own party.

The second pre-condition is the politicization of the American news media. In the current American media environment, sources of information on the pandemic are attributed widely agreed-upon and oft discussed political leanings (perhaps the two most salient being CNN, associated with “the left,” and Fox News, associated with “the right”). As a consequence, when Americans “interact” with news personalities who are also a salient source of endorsements or rejections of these health behaviors, political identities are extremely salient. This then sets the stage for correlations in health behavior rejection or endorsement among news personalities to create the cognitive association between their respective political identity and the endorsement of these health behaviors foreshadowed above in the minds of Americans.

An alternative explanation is as follows: individuals are uniformly subject to social influence from any particular source they are exposed to, but individuals will naturally be exposed more to sources that share their political identity. The result is that even slight chance variation in attitudes or behaviors at the outset will lead to much great differences over time. This explanation is consonant with explanations provided by Axelrod (1997) for cultural variation in general and DellaPosta et al (2015) for lifestyle politics in particular and accords with the popular concept of “political echo chambers”. It is worth noting that in this alternative explanation, cross-aisle interactions hamper behavioral differentiation, while from the lens of associative diffusion such interactions potentially accelerate and maintain it.

This alternative explanation, however, has difficulty in explaining why US Republicans went from mixed support of health behaviors to a more wide-spread rejection of these behaviors. Bursztyn et al (2020) documents how in the early days of the outbreak, two influential news anchors associated with the political right had discordant reactions to the burgeoning pandemic, with one downplaying the danger posed by the virus and the other taking it more seriously. During this same time, news anchors associated with the left showed a more united front, more universally endorsing caution. From the alternative explanation’s perspective, whether or not a more somber assessment of the virus would become the norm among American Republicans is essentially a coin flip—dependent completely upon what proportion of American Republicans were privately leaning towards endorsement at the outset. From the associative diffusion perspective, however, the outcome is more predictable: with mixed feelings in one group and largely unanimous feelings in the other, audiences watching these programs would see a correlation between rejecting these health behaviors and political identity – leading to a mutual embedding of the meaning of these practices and political orientation. What it meant to be an American conservative became, in part, rejecting these health behaviors, and vice versa.

This simple analysis elucidates several possible interventions to increase Republican endorsement of recommended health behaviors. First, the wide-spread shaming of Republicans writ large among Democrats will likely only serve to worsen the issue, as it will make more salient the behavioral disparities between the groups. Making examples of Republicans who endorse these health behaviors more salient could serve to lessen the troublesome perceived association. Additionally, the political identity of prominent instances of individuals or groups who happen to both identify as Republican and reject these health behaviors should be made as inconspicuous as possible, perhaps by focusing on other characteristics of the individuals (though this runs the risk of recreating these behavioral disparities along a different demographic axis). Finally, in discussions where the behavioral disparity along party lines has already been made salient, one should take a page from research on moral reframing (Feinberg and Willer 2015) and attempt to make salient connections between these health behaviors and values that are widely endorsed by US Republicans (e.g. patriotism and the sanctity of life).


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Bursztyn, L., Rao, A., Roth, C., & Yanagizawa-Drott, D. (2020). Misinformation during a pandemic. University of Chicago, Becker Friedman Institute for Economics Working Paper, (2020-44).

DellaPosta, D., Shi, Y., & Macy, M. (2015). Why do liberals drink lattes?. American Journal of Sociology120(5), 1473-1511.

Feinberg, M., & Willer, R. (2015). From gulf to bridge: When do moral arguments facilitate political influence?. Personality and Social Psychology Bulletin41(12), 1665-1681.

Goldberg, A., & Stein, S. K. (2018). Beyond social contagion: Associative diffusion and the emergence of cultural variation. American Sociological Review83(5), 897-932.

Iyengar, S., Lelkes, Y., Levendusky, M., Malhotra, N., & Westwood, S. J. (2019). The origins and consequences of affective polarization in the United States. Annual Review of Political Science22, 129-146.

Kushner Gadarian, S., Goodman, S. W., & Pepinsky, T. B. (2020). Partisanship, health behavior, and policy attitudes in the early stages of the COVID-19 pandemic. SSRN working paper.

van Loon, A., Goldberg, A., & Srivastava, S. (Manuscript under preparation). “Multilevel Construal Distance, Affective Polarization, and Dehumanization”.