Despite the recognized importance of addressing belief bias in critical thinking, little is known about the neural activity underlying belief-bias reasoning and its connection to critical thinking. The study utilized event-related potentials (ERPs) to examine the neural responses during belief-bias reasoning and explored the extent to which these ERPs explained individual differences in critical thinking. A sample of university students (N = 72) participated in a belief-bias syllogistic reasoning task while their electroencephalographic data were recorded. The task manipulated conflicts between belief and logic within each syllogism. Additionally, participants completed established tests to assess their critical thinking. Our findings revealed that participants with high levels of critical thinking exhibited larger amplitudes of the P600 and late positive component (LPC), indicating enhanced syntactic analysis and relation integration. Moreover, those with high levels of critical thinking displayed smaller N400 amplitudes, suggesting reduced reliance on automatic semantic processing. Notably, participants, especially those with high levels of critical thinking, demonstrated larger late negative component (LNC) amplitudes in response to incongruent syllogisms than to congruent syllogisms, highlighting their heightened capacity to address conflicts between belief and logic. Furthermore, regression analyses indicated that critical thinking relied on both addressing conflicts between belief and logic, as indexed by the LNC, and generating conclusions, as indexed by the P3 components (including both P600 and LPC). These findings contribute to the theoretical understanding of critical thinking by shedding light on the neural processes associated with unbiased reasoning and metacognition, as well as offer implications for assessing critical thinking.
Educational Impact and Implications StatementWe discovered that individuals who possess advanced critical thinking skills demonstrate greater brain activity measured by the P600, and late positive component, while exhibiting smaller N400 amplitudes compared to those with lower-level critical thinking skills. Moreover, variations in critical thinking among individuals can be predicted by the late negative component that reflects the resolution of conflicts between belief and logic during syllogistic reasoning, as well as the P3 components that indicate the generation of logical conclusions. These findings suggest that the electroencephalogram signals associated with solving belief-bias reasoning problems are significant indicators of critical thinking. This discovery offers valuable insights into identifying the neurophysiological markers of critical thinking, potentially leading to the creation of more objective and reliable assessment tools for intervention programs aimed at cultivating critical thinking skills.