Response to Greene: Moral sentiments and reason: friends or foes?

Abstract

We appreciate Greene's comments on our article [ 1 Greene J.D. Why are VMPFC patients more utilitarian? A dual-process theory of moral judgment explains. Trends Cogn. Sci. 2007; 11: 322-323 Abstract Full Text Full Text PDF PubMed Scopus (295) Google Scholar ]. We have argued that neither simple emotional blunting (i.e. somatic markers) nor Greene's dual-process view of opposing emotional and cognitive mechanisms would satisfactorily explain the Koenigs et al. findings on patients with ventromedial prefrontal cortex (VMPFC) damage [ 2 Koenigs M. Tranel D. Irrational economic decision-making after ventromedial prefrontal damage: evidence from the Ultimatum Game. J. Neurosci. 2007; 27: 951-956 Crossref PubMed Scopus (381) Google Scholar , 3 Koenigs M. et al. Damage to the prefrontal cortex increases utilitarian moral judgements. Nature. 2007; 446: 908-911 Crossref PubMed Scopus (1086) Google Scholar ]. Although these patients made more utilitarian choices in trolley-type dilemmas (i.e. less emotional and more rational decisions), they opted more often for costly punishing non-cooperators in the ultimatum game (i.e. they were more emotional). Based on experimental and theoretical grounds [ 4 Moll, J. et al. (2007) The cognitive neuroscience of moral emotions. In Moral Psychology (Vol. 3) (Morals and the Brain), (Sinnott-Armstrong, W., ed.), MIT Press (in press) Google Scholar , 5 Moll J. et al. The self as a moral agent: linking the neural bases of social agency and moral sensitivity. Social Neurosci. 2007; https://doi.org/10.1080/17470910701392024 Crossref PubMed Scopus (173) Google Scholar ], we contend that dissociation within the moral sentiment domain offers a more parsimonious explanation for these findings. In our view, the VMPFC and the frontopolar cortex (FPC), a region greatly expanded in humans [ 6 Allman J.A. et al. Two phylogenetic specializations in the human brain. Neuroscientist. 2002; 8: 335-346 Crossref PubMed Scopus (146) Google Scholar ], in conjunction with temporal and limbic-basal forebrain systems [ 5 Moll J. et al. The self as a moral agent: linking the neural bases of social agency and moral sensitivity. Social Neurosci. 2007; https://doi.org/10.1080/17470910701392024 Crossref PubMed Scopus (173) Google Scholar ], play a distinguished role in the experience of prosocial sentiments (i.e. guilt, compassion and interpersonal attachment), whereas the ventrolateral PFC is more relevant for the experience of anger or indignation. Reduced prosocial sentiments are compatible with increased ‘cold-blooded’ utilitarian choices in personal dilemmas [ 3 Koenigs M. et al. Damage to the prefrontal cortex increases utilitarian moral judgements. Nature. 2007; 446: 908-911 Crossref PubMed Scopus (1086) Google Scholar ], and preserved or increased punishment of others in the ultimatum game [ 2 Koenigs M. Tranel D. Irrational economic decision-making after ventromedial prefrontal damage: evidence from the Ultimatum Game. J. Neurosci. 2007; 27: 951-956 Crossref PubMed Scopus (381) Google Scholar ].