title: Harm to others outweighs harm to self in moral decision making.
abstract: Concern for the suffering of others is central to moral decision making. How humans evaluate others' suffering, relative to their own suffering, is unknown. We investigated this question by inviting subjects to trade off profits for themselves against pain experienced either by themselves or an anonymous other person. Subjects made choices between different amounts of money and different numbers of painful electric shocks. We independently varied the recipient of the shocks (self vs. other) and whether the choice involved paying to decrease pain or profiting by increasing pain. We built computational models to quantify the relative values subjects ascribed to pain for themselves and others in this setting. In two studies we show that most people valued others' pain more than their own pain. This was evident in a willingness to pay more to reduce others' pain than their own and a requirement for more compensation to increase others' pain relative to their own. This "hyperaltruistic" valuation of others' pain was linked to slower responding when making decisions that affected others, consistent with an engagement of deliberative processes in moral decision making. Subclinical psychopathic traits correlated negatively with aversion to pain for both self and others, in line with reports of aversive processing deficits in psychopathy. Our results provide evidence for a circumstance in which people care more for others than themselves. Determining the precise boundaries of this surprisingly prosocial disposition has implications for understanding human moral decision making and its disturbance in antisocial behavior.
authors.affiliation: Wellcome Trust Centre for Neuroimaging, University College London, London WC1N 3BG, United Kingdom; Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom; molly.crockett@psy.ox.ac.uk.
authors.forename: Molly J
authors.initials: MJ
authors.lastname: Crockett
authors.affiliation: Wellcome Trust Centre for Neuroimaging, University College London, London WC1N 3BG, United Kingdom; Max Planck-University College London Centre for Computational Psychiatry and Ageing, London WC1B 5EE, United Kingdom.
authors.forename: Zeb
authors.initials: Z
authors.lastname: Kurth-Nelson
authors.affiliation: Wellcome Trust Centre for Neuroimaging, University College London, London WC1N 3BG, United Kingdom; Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom;
authors.forename: Jenifer Z
authors.initials: JZ
authors.lastname: Siegel
authors.affiliation: Gatsby Computational Neuroscience Unit, University College London, London WC1N 3AR, United Kingdom; and.
authors.forename: Peter
authors.initials: P
authors.lastname: Dayan
authors.affiliation: Wellcome Trust Centre for Neuroimaging, University College London, London WC1N 3BG, United Kingdom; Max Planck-University College London Centre for Computational Psychiatry and Ageing, London WC1B 5EE, United Kingdom.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Dolan
mesh_terms: D000465:Algorithms; D000533:Altruism; D002755:Choice Behavior / Q000502:physiology*; D003657:Decision Making; D004597:Electroshock / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D009014:Morals; D010146:Pain / Q000209:etiology / Q000523:psychology*; D017288:Pain Threshold / Q000523:psychology; D011930:Reaction Time / Q000502:physiology; D012737:Sex Factors; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: altruism; decision making; morality; social preferences; valuation