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

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.

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 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.

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.