Language Nativeness Modulates Physiological Responses to Moral vs. Immoral Concepts in Chinese–English Bilinguals: Evidence from Event-Related Potential and Psychophysiological Measures

Morality has been an integral part of social cognition and our daily life, and different languages may exert distinct impacts on human moral judgment. However, it remains unclear how moral concept is encoded in the bilingual brain. This study, therefore, aimed to explore the emotional and cognitive involvement of bilingual morality judgement by using combined event-related potential (ERP) and psychophysiological (including skin, heart, and pulse) measures. In the experiment, thirty-one Chinese–English bilingual participants were asked to make moral judgments in Chinese and English, respectively. Our results revealed increased early frontal N400 and decreased LPC in L1 moral concept encoding as compared to L2, suggesting that L1 was more reliant on automatic processes and emotions yet less on elaboration. In contrast, L2 moral and immoral concepts elicited enhanced LPC, decreased N400, and greater automatic psychophysiological electrocardiograph responses, which might reflect more elaborate processing despite blunted emotional responses and increased anxiety. Additionally, both behavioral and P200 data revealed a reliable immorality bias across languages. Our results were discussed in light of the dual-process framework of moral judgments and the (dis)embodiment of bilingual processing, which may advance our understanding of the interplay between language and morality as well as between emotion and cognition.