title: Reduced resting-state functional connectivity of the somatosensory cortex predicts psychopathological symptoms in women with bulimia nervosa.
abstract: BACKGROUND
  Alterations in the resting-state functional connectivity (rs-FC) of several brain networks have been demonstrated in eating disorders. However, very few studies are currently available on brain network dysfunctions in bulimia nervosa (BN). The somatosensory network is central in processing body-related stimuli and it may be altered in BN. The present study therefore aimed to investigate rs-FC in the somatosensory network in bulimic women.
  
  
  METHODS
  Sixteen medication-free women with BN (age = 23 ± 5 years) and 18 matched controls (age = 23 ± 3 years) underwent a functional magnetic resonance resting-state scan and assessment of eating disorder symptoms. Within-network and seed-based functional connectivity analyses were conducted to assess rs-FC within the somatosensory network and to other areas of the brain.
  
  
  RESULTS
  Bulimia nervosa patients showed a decreased rs-FC both within the somatosensory network (t = 9.0, df = 1, P = 0.005) and with posterior cingulate cortex and two visual areas (the right middle occipital gyrus and the right cuneus) (P = 0.05 corrected for multiple comparison). The rs-FC of the left paracentral lobule with the right middle occipital gyrus correlated with psychopathology measures like bulimia (r = -0.4; P = 0.02) and interoceptive awareness (r = -0.4; P = 0.01). Analyses were conducted using age, BMI (body mass index), and depressive symptoms as covariates.
  
  
  CONCLUSIONS
  Our findings show a specific alteration of the rs-FC of the somatosensory cortex in BN patients, which correlates with eating disorder symptoms. The region in the right middle occipital gyrus is implicated in body processing and is known as extrastriate body area (EBA). The connectivity between the somatosensory cortex and the EBA might be related to dysfunctions in body image processing. The results should be considered preliminary due to the small sample size.
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy ; Institute of Mental Health Research, University of Ottawa, Royal Ottawa Healthcare Group , Ottawa, ON , Canada.
authors.forename: Luca
authors.initials: L
authors.lastname: Lavagnino
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Amianto
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: D'Agata
authors.affiliation: Institute of Mental Health Research, University of Ottawa, Royal Ottawa Healthcare Group , Ottawa, ON , Canada.
authors.forename: Zirui
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Mortara
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Abbate-Daga
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Enrica
authors.initials: E
authors.lastname: Marzola
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Angela
authors.initials: A
authors.lastname: Spalatro
authors.affiliation: Department of Neuroscience, AOU San Giovanni Battista , Turin , Italy.
authors.forename: Secondo
authors.initials: S
authors.lastname: Fassino
authors.affiliation: Institute of Mental Health Research, University of Ottawa, Royal Ottawa Healthcare Group , Ottawa, ON , Canada ; Graduate Institute of Humanities in Medicine, Taipei Medical University , Taipei , Taiwan ; Brain and Consciousness Research Center, Taipei Medical University-Shuang Ho Hospital , New Taipei City , Taiwan ; Research Center for Mind, Brain and Learning, National Chengchi University , Taipei , Taiwan ; Department of Psychology, National Chengchi University , Taipei , Taiwan ; Centre for Cognition and Brain Disorders (CCBD), Normal University Hangzhou , Hangzhou , China.
authors.forename: Georg
authors.initials: G
authors.lastname: Northoff
keywords: bulimia; eating disorders; fMRI; functional connectivity; resting state; somatosensory network