Political ideology, mood response, and the confirmation bias

The confirmation bias is a well-known form of motivated reasoning that serves to protect an individual from discomfort. Hearing opposing viewpoints or information creates cognitive dissonance, and so avoiding exposure to, or discounting the validity of, dissonant information are rational strategies that may help avoid or mitigate negative emotion. Because there is often a systematic thought process involved in generating the confirmation bias, deliberation tends to promote this behavioral bias. Nevertheless, the importance of negative emotion in triggering the need for this bias is an underappreciated facet of the confirmation bias. This paper addresses this gap in the literature by examining mood and the confirmation bias in the political domain. Using data from two studies and three distinct decision tasks, we present data on over 1100 participants (Study 1, n=611; Study 2, n=503) that document the confirmation bias in different settings. Specifically, task 1 (Study 1) examines perceptions of opposing argument strength in a classic confirmation bias task. Task 2 (Study 1) is a novel task that measures the change in one’s perceptions and normative preferences regarding political issues after receipt of a random issue-specific informational message. Finally, Task 3 (Study 2) administers a Bayesian decision task to examine one’s belief-updating regarding the truthfulness of factual political statements after receipt of a noisy signal about whether the statement is true or false. All methods (recruitment and sample size, hypotheses, variables, analysis plans, etc.) were preregistered on the Open Science Framework. Our data show evidence of a confirmation bias across the variety of tasks administered, which covered distinct dimensions of belief and preference formation. As hypothesized, the data show a strong increase in self-reported negative mood states after viewing political statements or information that are dissonant with one’s political ideology. Finally, while not as robust across tasks, we report evidence that supports our hypothesis that negative mood will moderate the strength of the confirmation bias. Together, these results highlight the importance of mood response in understanding the confirmation bias, which helps further our understanding of how this bias may be particularly difficult to combat. Key Words: confirmation bias; sleep; deliberation; cognitive reflection; motivated reasoning