title: Reduced brainstem inhibition during anticipated pelvic visceral pain correlates with enhanced brain response to the visceral stimulus in women with irritable bowel syndrome.
abstract: Cognitive factors such as fear of pain and symptom-related anxiety play an important role in chronic pain states. The current study sought to characterize abnormalities in preparatory brain response before aversive pelvic visceral distention in irritable bowel syndrome (IBS) patients and their possible relationship to the consequences of distention. The brain functional magnetic resonance imaging (fMRI) blood oxygen level-dependent (BOLD) response to anticipated and delivered mild and moderate rectal distention was recorded from 14 female IBS patients and 12 healthy controls. During cued anticipation of distention, activity decreased in the insula, supragenual anterior cingulate cortex (sACC), amygdala, and dorsal brainstem (DBS) of controls. IBS patients showed less anticipatory inactivation. Group differences were significant in the right posterior insula and bilateral DBS. Self-rated measures of negative affect during scanning were higher in patients than controls (p < 0.001), and the anticipatory BOLD decreases in DBS were inversely correlated with these ratings. During subsequent distention, both groups showed activity increases in insula, dorsal ACC, and DBS and decreases in the infragenual ACC. The increases were more extensive in patients, producing significant group differences in dorsal ACC and DBS. The amplitude of the anticipatory decrease in the pontine portion of DBS was associated with greater activation during distention in right orbitofrontal cortex and bilateral sACC. Both regions have been associated previously with corticolimbic inhibition and cognitive coping. Deficits in preparatory inhibition of DBS, including the locus ceruleus complex and parabrachial nuclei, may interfere with descending corticolimbic inhibition and contribute to enhanced brain responsiveness and perceptual sensitivity to visceral stimuli in IBS.
authors.affiliation: Department of Medicine, University of California, Los Angeles Center for Neurovisceral Sciences and Women's Health, David Geffen School of Medicine at University of California, Los Angeles, 90073, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Berman
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Naliboff
authors.forename: Brandall
authors.initials: B
authors.lastname: Suyenobu
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Labus
authors.forename: Jean
authors.initials: J
authors.lastname: Stains
authors.forename: Gordon
authors.initials: G
authors.lastname: Ohning
authors.forename: Lisa
authors.initials: L
authors.lastname: Kilpatrick
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Bueller
authors.forename: Kim
authors.initials: K
authors.lastname: Ruby
authors.forename: Johanna
authors.initials: J
authors.lastname: Jarcho
authors.forename: Emeran A
authors.initials: EA
authors.lastname: Mayer
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D001933:Brain Stem / Q000098:blood supply / Q000503:physiopathology*; D002404:Catheterization; D003463:Cues; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007266:Inhibition, Psychological; D043183:Irritable Bowel Syndrome / Q000150:complications* / Q000534:rehabilitation; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D019964:Mood Disorders / Q000209:etiology; D010100:Oxygen / Q000097:blood; D017288:Pain Threshold; D017699:Pelvic Pain / Q000209:etiology* / Q000534:rehabilitation; D010812:Physical Stimulation / Q000379:methods; D012007:Rectum / Q000503:physiopathology; D012720:Severity of Illness Index; D014781:Viscera / Q000294:innervation* / Q000503:physiopathology
chemical_list: D010100:Oxygen