Neural correlates of moral goodness and moral beauty judgments

Abstract

The objects of moral goodness and moral beauty judgments both generally refer to the positive moral acts or virtues of humans, and goodness must precede moral beauty. The main difference is that moral beauty, but not moral goodness, triggers emotional elevation. However, little is known about the neural mechanisms involved in both judgments. In the current study, 28 healthy female participants were scanned when they rated the good and beautiful extent of positive moral acts in daily life depicted in scene drawings to investigate the neural systems supporting moral goodness and moral beauty, specifically to test whether neural activity associated with moral beauty is same or different than moral goodness. The conjunction analysis of the contrasts between moral goodness judgment and moral beauty judgment identified the involvement of the left inferior orbitofrontal cortex (OFC), suggesting that the two judgments recruited the activity of a common brain region. Importantly, compared with the moral goodness judgment, the moral beauty judgment induced greater activity in more advanced cortical regions implicated in elevated emotions, including the anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), superior frontal gyrus (SFG) and the left temporo-parietal junction (TPJ). These regions have been strongly correlated with the cognitive aspects of moral cognition, including theory of mind (ToM). In addition, moral beauty judgment also activated brain regions implicated in empathy including the midline structures and the anterior insula. Based on these results, the brain harbors neural systems for common and for domain-specific evaluations of moral goodness and moral beauty judgments. Our study thus provides novel and compelling neural evidence for the essence of moral beauty and advances the current knowledge of the neural mechanisms underlying the beauty-is-good stereotype.