title: Exploring the brain in pain: activations, deactivations and their relation.
abstract: The majority of neuroimaging studies on pain focuses on the study of BOLD activations, and more rarely on deactivations. In this study, in a relatively large cohort of subjects (N=61), we assess (a) the extent of brain activation and deactivation during the application of two different heat pain levels (HIGH and LOW) and (b) the relations between these two directions of fMRI signal change. Furthermore, in a subset of our subjects (N=12), we assess (c) the functional connectivity of pain-activated or -deactivated regions during resting states. As previously observed, we find that pain stimuli induce intensity dependent (HIGH pain>LOW pain) fMRI signal increases across the pain matrix. Simultaneously, the noxious stimuli induce activity decreases in several brain regions, including some of the 'core structures' of the default network (DMN). In contrast to what we observe with the signal increases, the extent of deactivations is greater for LOW than HIGH pain stimuli. The functional dissociation between activated and deactivated networks is further supported by correlational and functional connectivity analyses. Our results illustrate the absence of a linear relationship between pain activations and deactivations, and therefore suggest that these brain signal changes underlie different aspects of the pain experience.
authors.affiliation: Department of Psychiatry, Massachusetts General Hospital (MGH), Harvard Medical School, Charlestown, MA, USA MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA MGH/MIT CRC Biomedical Imaging Core, Charlestown, MA, USA Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Kong
authors.forename: Marco L
authors.initials: ML
authors.lastname: Loggia
authors.forename: Carolyn
authors.initials: C
authors.lastname: Zyloney
authors.forename: Peichi
authors.initials: P
authors.lastname: Tu
authors.forename: Peter
authors.initials: P
authors.lastname: LaViolette
authors.forename: Randy L
authors.initials: RL
authors.lastname: Gollub
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D005542:Forearm / Q000294:innervation; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000098:blood supply; D010100:Oxygen / Q000097:blood; D010146:Pain / Q000473:pathology*; D010147:Pain Measurement / Q000379:methods; D017288:Pain Threshold / Q000502:physiology*; D012737:Sex Factors; D013223:Statistics as Topic; D055815:Young Adult
chemical_list: D010100:Oxygen