Les émotions morales : approche psychologique et neurofonctionnelle

Converging evidence in neuroscience and psychology has recently suggested that moral behaviour relies to a greater extent on affective mechanisms than on cognitive processes. On the one hand social psychology studies have demonstrated that moral emotions, in particular guilt and empathy, are powerful driving forces behind moral behaviour. On the other hand, neuroimaging experiments, as well as studies on brain lesions, have highlighted that the cerebral processing of moral situations involves networks underlying emotions appraisal and regulation. The present study aimed at connecting these different levels of investigation in order to explore the relations between: (1) altruism (cash donation to charities), (2) personality traits (notably guilt, empathy and anxiety proneness, moral reasoning) and (3) cerebral activity in response to moral stimuli (self-anger, guilt, other-anger and compassion inducing situations) as measured by functional magnetic resonance imaging (fMRI). Results indicated that higher guilt proneness and state anxiety in participants were associated with donating money. Moreover, guilt and anxiety were the only personality traits to be correlated with brain activations, especially in structures of the limbic system – i. E. The insula and ventromedial prefrontal cortex – that have been shown to play a crucial role in social decision-making. Finally, our fMRI data revealed that picturing oneself in guilt inducing situations activated the same network, including the amygdala and insula. Therefore, these results strongly suggest that guilt and anxiety play a major role in the processing of moral situations and in motivating altruistic behaviour.