title: Increasing the role of belief information in moral judgments by stimulating the right temporoparietal junction.
abstract: Morality plays a vital role in our social life. A vast body of research has suggested that moral judgments rely on cognitive processes mediated by the right temporoparietal junction (rTPJ), an area thought to be involved in belief attribution. Here we assessed the role of the rTPJ in moral judgments directly by means of transcranial direct current stimulation (tDCS)--a non-invasive brain stimulation technique that, by applying a weak current to the scalp, allows modulating cortical excitability of the area being stimulated. Participants were randomly and equally assigned to receive anodal stimulation (to increase cortical excitability), cathodal stimulation (to decrease cortical excitability), or sham (placebo) stimulation over the rTPJ before completing a moral judgment task. Participants read stories in which protagonists produced either a negative or a neutral outcome based on either a negative or a neutral belief that they were causing harm or no harm, respectively. Results revealed a selective group difference when judging the moral permissibility of accidental harms (belief neutral, outcome negative), but not intentional harms (belief negative, outcome negative), attempted harms (belief negative, outcome neutral), or neutral acts (belief neutral, outcome neutral). Specifically, participants who received anodal stimulation assigned less blame to accidental harms compared to participants who received cathodal or sham stimulation. These results are consistent with previous findings showing that the degree of rTPJ activation reflects reliance on the agent's innocent intention. Crucially, our findings provide direct evidence supporting the critical role of the rTPJ in mediating belief attribution for moral judgment.
authors.affiliation: Cognitive Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands. Electronic address: r.sellaro@fsw.leidenuniv.nl.
authors.forename: Roberta
authors.initials: R
authors.lastname: Sellaro
authors.affiliation: Developmental and Educational Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
authors.forename: Berna
authors.initials: B
authors.lastname: Güroǧlu
authors.affiliation: Department of Clinical Neurophysiology, Georg-August University Göttingen, Göttingen, Germany; Leibniz Research Centre for Working Environment and Human Resources, Dortmund, Germany; Department of Neurology, University Medical Hospital Bergmannsheil, Bochum, Germany.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Nitsche
authors.affiliation: Department of Psychology & Amsterdam Brain & Cognition (ABC), University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Wery P M
authors.initials: WP
authors.lastname: van den Wildenberg
authors.affiliation: Cognitive Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
authors.forename: Valentina
authors.initials: V
authors.lastname: Massaro
authors.affiliation: Cognitive Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Durieux
authors.affiliation: Cognitive Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Hommel
authors.affiliation: Cognitive Psychology Unit & Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.
authors.forename: Lorenza S
authors.initials: LS
authors.lastname: Colzato
mesh_terms: D003657:Decision Making / Q000502:physiology*; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology*; D008297:Male; D009014:Morals; D010296:Parietal Lobe / Q000502:physiology*; D011897:Random Allocation; D016037:Single-Blind Method; D013702:Temporal Lobe / Q000502:physiology*; D065908:Transcranial Direct Current Stimulation; D055815:Young Adult
keywords: Belief; Moral judgment; Right temporoparietal junction; Transcranial direct current stimulation