Cognitive processes based on dichotomous belief

One of the subscales of dichotomous thinking, also known as black-and-white thinking, is a belief called “Dichotomous Belief.” This belief refers to the idea that everything can be divided into two categories, such as “the world only has winners and losers” or “people can be clearly divided into ‘good’ and ‘bad’” [1]. When value judgments based on this belief are applied or asserted to issues lacking objective criteria, such as ethical problems, they can cause conflict and develop into social issues. While associations between holding dichotomous beliefs and various individual differences—such as personality traits, cognitive abilities, and harsh upbringing environments—have been noted [2,3], previous research has primarily relied on questionnaire-based subjective self-concepts as measures of individual differences. Consequently, the neural basis underlying these beliefs and related individual variations remain unclear. Previous research on the neural basis of belief processing has shown that evaluating the truth of non-testable propositions (e.g., ethics) engages different brain regions than evaluating propositions where objective verification based on facts is possible (e.g., geography) [4]. This suggests that even when categorizing actions into two categories beyond truth/false, different cognitive processes may be used depending on the testability of the target event. Therefore, this study treats testable stimulus statements as the control condition. This study aims to clarify how individual differences in dichotomous beliefs manifest as differences in cognitive processes. This is crucial for elucidating the thinking of people who, faced with proliferating binary oppositions amid Information Disorder caused by Disinformation, Malinformation, etc., engage in disputes by treating the space between black and white as non-existent. At a time when enhancing the information literacy of the entire population is increasingly demanded to counter the threat of social division, this study aims to provide insights contributing to social stability from a cognitive science perspective.