title: Caudal cingulate cortex involvement in pain processing: an inter-individual laser evoked potential source localisation study using realistic head models.
abstract: Electrophysiological studies have revealed a source of laser pain evoked potentials (LEPs) in cingulate cortex. However, few studies have used realistically shaped head models in the source analysis, which account for individual differences in anatomy and allow detailed anatomical localisation of sources. The aim of the current study was to accurately localise the cingulate source of LEPs in a group of healthy volunteers, using realistic head models, and to assess the inter-individual variability in anatomical location. LEPs, elicited by painful CO(2) laser stimulation of the right forearm, were recorded from 62 electrodes in five healthy subjects. Dipole source localisation (CURRY 4.0) was performed on the most prominent (P2) peak of each LEP data set, using head models derived from each subject's structural magnetic resonance image (MRI).For all subjects, the P2 LEP peak was best explained by a dipole whose origin was in cingulate cortex (mean residual variance was 3.9+/-2.4 %). For four out of five subjects, it was located at the border of the caudal division of left anterior cingulate cortex (area 24/32') with left posterior cingulate cortex (area 23/31). For the fifth subject the dipole was centred in right posterior cingulate cortex (area 31). This study demonstrates that the location of the cingulate source of LEPs is highly consistent across subjects, when analysed in this way, and supports the involvement of caudal cingulate regions in pain processing.
authors.affiliation: Human Pain Research Group, University of Manchester Rheumatic Diseases Centre, Clinical Sciences Building, Hope Hospital, Salford M6 8HD, UK Department of Anaesthesiology, University of Pittsburgh Medical Centre, 200 Lothrop Street, Pittsburgh, PA 15213, USA Laser Photonics, Department of Physics and Astronomy, Schuster Laboratory, The University of Manchester, Brunswick Street, Manchester M13 9PL, UK.
authors.forename: Deborah E
authors.initials: DE
authors.lastname: Bentley
authors.forename: Stuart W G
authors.initials: SWG
authors.lastname: Derbyshire
authors.forename: Paula D
authors.initials: PD
authors.lastname: Youell
authors.forename: Anthony K P
authors.initials: AKP
authors.lastname: Jones
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006179:Gyrus Cinguli / Q000502:physiology*; D006801:Humans; D007834:Lasers; D008297:Male; D008953:Models, Anatomic; D010146:Pain / Q000503:physiopathology*