Evidence for ideological confirmation, or how to politicize color intensity perceptions

Political groups may form based in genuine differences between people, but once formed, these groups and their associated identities can influence people's views and behavior. In line with social-constraint models, we tested whether liberals and conservatives would report arbitrary perceptual experiences because those experiences were situationally framed as signals of political identity. Participants completed a bogus diagnostic task in which perceiving colors as becoming either more or less intense ostensibly signaled possession of a liberal or conservative brain type. In Experiments 1 and 2, participants were told which intensity experience signaled brain possession prior to completing the task; findings showed that liberal and conservative participants provided reports of color intensity in ways that confirmed their ideological identity. In Experiment 3, participants were told which intensity experience signaled brain possession only after a trial on the task; still, participants reported experiencing color in identity-confirming ways. These effects occurred in college and online adult samples, among participants who indicated unbiased responding, and the effects could not be attributed to left- or right-wing authoritarianism; moreover, the effects were associated with self-judgments and evaluations of others. Political identities do not merely bias how people feel about value-laden political information; rather, they can influence people to adopt arbitrary social symbols that, once adopted, may create the perception of real divides.