title: Beta adrenergic blockade reduces utilitarian judgement.
abstract: Noradrenergic pathways are involved in mediating the central and peripheral effects of physiological arousal. The aim of the present study was to investigate the role of noradrenergic transmission in moral decision-making. We studied the effects in healthy volunteers of propranolol (a noradrenergic beta-adrenoceptor antagonist) on moral judgement in a set of moral dilemmas pitting utilitarian outcomes (e.g., saving five lives) against highly aversive harmful actions (e.g., killing an innocent person) in a double-blind, placebo-controlled, parallel group design. Propranolol (40 mg orally) significantly reduced heart rate, but had no effect on self-reported mood. Importantly, propranolol made participants more likely to judge harmful actions as morally unacceptable, but only in dilemmas where harms were 'up close and personal'. In addition, longer response times for such personal dilemmas were only found for the placebo group. Finally, judgments in personal dilemmas by the propranolol group were more decisive. These findings indicate that noradrenergic pathways play a role in responses to moral dilemmas, in line with recent work implicating emotion in moral decision-making. However, contrary to current theorising, these findings also suggest that aversion to harming is not driven by emotional arousal. Our findings are also of significant practical interest given that propranolol is a widely used drug in different settings, and is currently being considered as a potential treatment for post-traumatic stress disorder in military and rescue service personnel.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Terbeck
authors.affiliation: University of Oxford, Department of Experimental Psychology, South Parks Road, Oxford OX1 3UD, England, United Kingdom. sylvia.terbeck@psy.ox.ac.uk
authors.forename: Terbeck
authors.initials: T
authors.lastname: Sylvia
authors.forename: Guy
authors.initials: G
authors.lastname: Kahane
authors.forename: Kahane
authors.initials: K
authors.lastname: Guy
authors.forename: Sarah
authors.initials: S
authors.lastname: McTavish
authors.forename: McTavish
authors.initials: M
authors.lastname: Sarah
authors.forename: Julian
authors.initials: J
authors.lastname: Savulescu
authors.forename: Savulescu
authors.initials: S
authors.lastname: Julian
authors.forename: Neil
authors.initials: N
authors.lastname: Levy
authors.forename: Levy
authors.initials: L
authors.lastname: Neil
authors.forename: Miles
authors.initials: M
authors.lastname: Hewstone
authors.forename: Hewstone
authors.initials: H
authors.lastname: Miles
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Cowen
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000328:Adult; D000704:Analysis of Variance; D003657:Decision Making / Q000187:drug effects*; D004311:Double-Blind Method; D028663:Ethical Theory; D005260:Female; D006801:Humans; D007600:Judgment / Q000187:drug effects* / Q000941:ethics; D008297:Male; D010147:Pain Measurement; D011433:Propranolol / Q000494:pharmacology*; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D013997:Time Factors; D055815:Young Adult
chemical_list: D000319:Adrenergic beta-Antagonists; D011433:Propranolol