Neural correlates of affective self-positivity bias in first and second languages.

Introduction: An inherent positive bias emerges when individuals perceive themselves compared to when they perceive others. However, for bilinguals, it has been suggested that this self-positivity bias may be sensitive to the language in which information is presented. Methods: In this study, we examine this hypothesis among a group of Chinese-English bilinguals who performed a lexical decision task in their first (L1, Chinese) and second (L2, English) language. During the experiment, brain activity was recorded using functional Magnetic Resonance Imaging (fMRI). Results: Results showed faster responses and decreased activity in the right medial frontal gyrus (RMFG) for self-positivity compared to other-positivity conditions in the L2 context. However, this identified self-positivity bias in the L2 elicited less engagement of the RMFG than that in the L1. Discussion: These findings reveal distinct mechanisms across languages that underpin the self-positivity bias. Self-positivity bias is processed more embodied in an L1, drawing on richer emotional associations, whereas self-positivity bias is processed in a disembodied way in an L2, which requires integration of affective and lexical information.