Neural Substrates of the Interplay between Cognitive Loading and Emotional Involvement in Bilingual Decision Making

Prior work investigated how foreign language impacts decision making by either reducing access to emotion or imposing additional cognitive demands. In this fMRI study, we employed a cross-task design to assess at the neural level whether and how the interaction between cognitive loading and emotional involvement is affected by language (native L1 vs. foreign L2). Participants completed a Lexico-semantic task where in each trial they were presented with either a neutrally or a negatively valenced word either in L1 or L2, and either under cognitive loading or not. After each trial, they had to decide whether to take a risky decision within a gambling game. During the Gamling task, left amygdala and right insula were more activated after having processed a negative word under cognitive loading. However, this was true for L1 but not for L2, suggesting that cognitive loading was germane and facilitated rather than hindered access to emotion only in L1. Further suggesting that cognitive load can enhance emotional sensitivity in L1 but not in L2, we found that functional connectivity between reward-related striatum and right insula increased under cognitive loading only in L1. Overall, results suggest that cognitive loading in L1 can favor access to emotion and lead to a more impulsive decision making, whereas cognitive loading in L2 can attenuate access to emotion and lead to a more rational decision making.