title: Placebo and opioid analgesia-- imaging a shared neuronal network.
abstract: It has been suggested that placebo analgesia involves both higher order cognitive networks and endogenous opioid systems. The rostral anterior cingulate cortex (rACC) and the brainstem are implicated in opioid analgesia, suggesting a similar role for these structures in placebo analgesia. Using positron emission tomography, we confirmed that both opioid and placebo analgesia are associated with increased activity in the rACC. We also observed a covariation between the activity in the rACC and the brainstem during both opioid and placebo analgesia, but not during the pain-only condition. These findings indicate a related neural mechanism in placebo and opioid analgesia.
authors.affiliation: Cognitive Neurophysiology Research Group, Department of Clinical Neuroscience, Karolinska Institute, Stockholm 171 76, Sweden., Pain Clinic, Department of Anaesthesia and Intensive Care Medicine, Helsinki University Hospital, Finland.
authors.forename: Predrag
authors.initials: P
authors.lastname: Petrovic
authors.forename: Eija
authors.initials: E
authors.lastname: Kalso
authors.forename: Karl Magnus
authors.initials: KM
authors.lastname: Petersson
authors.forename: Martin
authors.initials: M
authors.lastname: Ingvar
mesh_terms: D000328:Adult; D000698:Analgesia; D000701:Analgesics, Opioid / Q000494:pharmacology*; D001933:Brain Stem / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D002560:Cerebrovascular Circulation; D006179:Gyrus Cinguli / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D010146:Pain; D010147:Pain Measurement; D010880:Piperidines / Q000494:pharmacology; D015990:Placebo Effect; D010919:Placebos / Q000494:pharmacology*; D011957:Receptors, Opioid / Q000378:metabolism; D000077208:Remifentanil; D014055:Tomography, Emission-Computed
chemical_list: D000701:Analgesics, Opioid; D010880:Piperidines; D010919:Placebos; D011957:Receptors, Opioid; D000077208:Remifentanil