Neural Evaluation of Educational Videos: Potential Disadvantage of Combining Hazard-Mechanism Explanation and Evacuation Instruction Messages

This study examined the educational effectiveness of combining hazard-mechanism explanations and evacuation instructions in tsunami-related video messages, using both behavioral and neural measures. University students were assigned to one of four groups (mechanism, evacuation, combination, or control) and exposed to video materials while undergoing fMRI. The educational effect was assessed by changes in evacuation intent in a scenario-based decision-making task before and after video exposure. Results showed that all tsunami-related video groups had higher increases in evacuation intent than the control group, confirming that both mechanism and evacuation content were effective. However, the combined condition did not produce additional behavioral benefits. Neuroimaging analysis revealed diminished activation in five cortical regions related to self-referential processing (posterior cingulate cortex (PCC)), visual processing (lingual gyrus and inferior occipital gyrus), and auditory processing (bilateral superior temporal gurus) in the combination group compared to the evacuation-only group. Importantly, PCC activity was positively correlated with increased evacuation intent, suggesting its role as a neural index of educational effectiveness. These findings indicate that although hazard-mechanism and evacuation-instruction videos are individually effective, their combination may impose cognitive load that undermines self-referential processing and reduces neural engagement. Implications for the design of disaster education materials highlight the importance of balancing informational richness with cognitive processing demands to optimize preparedness outcomes.