Jorge Moll, Ricardo de Oliveira-Souza, Paul J. Eslinger, Ivanei E. Bramati, Janaina Mourao-Miranda, Pedro Angelo Andreiuolo, Luiz Pessoa The Neural Correlates of Moral Sensitivity: A Functional Magnetic Resonance Imaging Investigation of Basic Moral Emotions, Journal of Neuroscience, 2002, 22 (7), pp. 2730-2736.
Thesis 1: Moral emotions play a key role in assigning moral values, being an implicit social behaviour in humans.
Thesis 2: Orbital and medial sectors of the prefrontal cortex and the superior temporal sulculus (STS) are critical regions for moral appraisal.
(b) Experimental setting:
Experiment: Subjects were presented with six categories of pictures: (1) moral pictures portraying emotionally charged, unpleasant social scenes, representing moral violations; (2) unpleasant pictures of aversive scenes not conveying moral connotations; (3) pleasant pictures, including scenes of people and landscapes; (4) ‘interesting’ pictures, which were visually arousing but less emotional; (5) neutral pictures, including people and landscapes; (6) scrambled images. The goal of the experiment was to investigate spontaneus brain responses triggered by the perception of this visual stimuli. The results showed an increased activation of the right medial orbital prefrontal cortex (OFC) and the medial frontal gyrus (MedFG) and the cortex surrounding the right STS while viewing moral in comparison with nonmoral scenes.
2. Critical comments:
1) The experiment revealed that viewing moral and nonmoral unpleasant visual stimuli activated very similar brain regions. Effects of the moral stimuli cannot be explained on the basis of emotional valence or visual arousal alone. Moral emotions differ from basic emotions in that they are interpersonal. However, if it is so, moral emotions are similar to basic ones, only in the aspect of being a quick and automatic response to a certain situation. Apart from this emotional aspect of moral emotions, they seem to require mechanism specific to moral domain, that enables to recognize certain situation as moral.
2) Because the experiment consisted only in presenting visual stimuli to participants, it exhausts only one mode of presentation of moral situations. However, subjects may encounter ‘moral content’ in other ‘forms’. For example, it was shown that explicit moral reasoning activates additional prefrontal regions to OFC, MedFG and STS.