title: Placebo analgesia and its opioidergic regulation suggest that empathy for pain is grounded in self pain.
abstract: Empathy for pain activates brain areas partially overlapping with those underpinning the first-hand experience of pain. It remains unclear, however, whether such shared activations imply that pain empathy engages similar neural functions as first-hand pain experiences. To overcome the limitations of previous neuroimaging research, we pursued a conceptually novel approach: we used the phenomenon of placebo analgesia to experimentally reduce the first-hand experience of pain, and assessed whether this results in a concomitant reduction of empathy for pain. We first carried out a functional MRI experiment (n = 102) that yielded results in the expected direction: participants experiencing placebo analgesia also reported decreased empathy for pain, and this was associated with reduced engagement of anterior insular and midcingulate cortex: that is, areas previously associated with shared activations in pain and empathy for pain. In a second step, we used a psychopharmacological manipulation (n = 50) to determine whether these effects can be blocked via an opioid antagonist. The administration of the opioid antagonist naltrexone blocked placebo analgesia and also resulted in a corresponding "normalization" of empathy for pain. Taken together, these findings suggest that pain empathy may be associated with neural responses and neurotransmitter activity engaged during first-hand pain, and thus might indeed be grounded in our own pain experiences.
authors.affiliation: Social, Cognitive and Affective Neuroscience Unit, Department of Basic Psychological Research and Research Methods, Faculty of Psychology, University of Vienna, Vienna 1010, Austria;
authors.forename: Markus
authors.initials: M
authors.lastname: Rütgen
authors.affiliation: Social, Cognitive and Affective Neuroscience Unit, Department of Basic Psychological Research and Research Methods, Faculty of Psychology, University of Vienna, Vienna 1010, Austria;
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Seidel
authors.affiliation: Cognitive Neuroscience Sector, International School for Advanced Studies, Trieste 34136, Italy; Department of Applied Psychology: Health, Development, Enhancement and Intervention, Faculty of Psychology, University of Vienna, Vienna 1010, Austria;
authors.forename: Giorgia
authors.initials: G
authors.lastname: Silani
authors.affiliation: Social, Cognitive and Affective Neuroscience Unit, Department of Basic Psychological Research and Research Methods, Faculty of Psychology, University of Vienna, Vienna 1010, Austria; Laboratory of Cognitive Neuroscience, Institute of Normal and Pathological Physiology, Centre of Excellence for Examination of Regulatory Role of Nitric Oxide in Civilization diseases, Slovak Academy of Sciences, Bratislava 813 71, Slovakia;
authors.forename: Igor
authors.initials: I
authors.lastname: Riečanský
authors.affiliation: Medical Research (MR) Center of Excellence, Medical University of Vienna, Vienna 1090, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna 1090, Austria;
authors.forename: Allan
authors.initials: A
authors.lastname: Hummer
authors.affiliation: Medical Research (MR) Center of Excellence, Medical University of Vienna, Vienna 1090, Austria; Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna 1090, Austria;
authors.forename: Christian
authors.initials: C
authors.lastname: Windischberger
authors.affiliation: Cognitive Neurophysiology Research Group, Department of Clinical Neuroscience, Karolinska Institute, Stockholm 171 76, Sweden.
authors.forename: Predrag
authors.initials: P
authors.lastname: Petrovic
authors.affiliation: Social, Cognitive and Affective Neuroscience Unit, Department of Basic Psychological Research and Research Methods, Faculty of Psychology, University of Vienna, Vienna 1010, Austria; claus.lamm@univie.ac.at.
authors.forename: Claus
authors.initials: C
authors.lastname: Lamm
mesh_terms: D000328:Adult; D000698:Analgesia; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004645:Empathy; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009271:Naltrexone / Q000008:administration & dosage*; D009292:Narcotic Antagonists / Q000008:administration & dosage*; D059906:Neuroimaging; D010146:Pain / Q000000981:diagnostic imaging / Q000503:physiopathology*; D015990:Placebo Effect; D011859:Radiography
chemical_list: D009292:Narcotic Antagonists; D009271:Naltrexone
keywords: empathy; fMRI; pain; placebo; psychopharmacology