title: Local cortical thinning links to resting-state disconnectivity in major depressive disorder.
abstract: BACKGROUND
  Local structural and metabolic as well as inter-regional connectivity abnormalities have been implicated in the neuropathology of major depressive disorder (MDD). How local tissue properties affect intrinsic functional connectivity is, however, unclear. Using a cross-sectional, multi-modal imaging approach, we investigated the relationship between local cortical tissue abnormalities and intrinsic resting-state functional connectivity (RSFC) in MDD.
  
  
  METHODS
  A total of 20 MDD in-patients and 20 healthy controls underwent magnetic resonance imaging at 3 T for structural and functional imaging. Whole-brain cortical thickness was calculated and compared between groups. Regions with reduced cortical thickness defined seeds for subsequent whole-brain RSFC analyses. Contributions of structural tissue abnormalities on inter-regional RSFC were explicitly investigated.
  
  
  RESULTS
  Lower cortical thickness was observed in MDD in the right dorsomedial prefrontal cortex (PFC), superior temporal gyrus/temporal pole, middle-posterior cingulate cortex, and dorsolateral PFC. No differences in local fractional amplitude of low-frequency fluctuations were observed. Lower thickness in patients' dorsomedial PFC further directly and selectively affected its RSFC with the precuneus, which was unaffected by symptom severity. No effects of cortical thickness in other regions showing abnormal thickness were observed to influence functional connectivity.
  
  
  CONCLUSIONS
  Abnormal cortical thickness in the dorsomedial PFC in MDD patients was observed to selectively and directly affect its intrinsic connectivity with the precuneus in MDD patients independent of depression severity, thereby marking a potential vulnerability for maladaptive mood regulation. Future studies should include an unmedicated sample and replicate findings using independent component analysis to test for morphometric effects on network integrity.
authors.affiliation: NeuroImaging Center,University Medical Center Groningen, University of Groningen,Groningen,The Netherlands.
authors.forename: M-J
authors.initials: MJ
authors.lastname: van Tol
authors.affiliation: Leibniz Institute for Neurobiology, Magdeburg,Germany.
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.affiliation: Leibniz Institute for Neurobiology, Magdeburg,Germany.
authors.forename: C D
authors.initials: CD
authors.lastname: Metzger
authors.affiliation: Clinical Affective Neuroimaging Laboratory,Center for Behavioral Brain Sciences,Magdeburg,Germany.
authors.forename: N
authors.initials: N
authors.lastname: Hailla
authors.affiliation: Clinical Affective Neuroimaging Laboratory,Center for Behavioral Brain Sciences,Magdeburg,Germany.
authors.forename: D I
authors.initials: DI
authors.lastname: Horn
authors.affiliation: Leibniz Institute for Neurobiology, Magdeburg,Germany.
authors.forename: W
authors.initials: W
authors.lastname: Li
authors.affiliation: Leibniz Institute for Neurobiology, Magdeburg,Germany.
authors.forename: H J
authors.initials: HJ
authors.lastname: Heinze
authors.affiliation: Department of Psychiatry and Psychotherapy,Otto von Guericke University,Magdeburg,Germany.
authors.forename: B
authors.initials: B
authors.lastname: Bogerts
authors.affiliation: Department of Psychiatry and Psychotherapy,Otto von Guericke University,Magdeburg,Germany.
authors.forename: J
authors.initials: J
authors.lastname: Steiner
authors.affiliation: State Key Laboratory of Management and Control for Complex Systems, Institute of Automation,Chinese Academy of Sciences,Beijing,People's Republic of China.
authors.forename: H
authors.initials: H
authors.lastname: He
authors.affiliation: Leibniz Institute for Neurobiology, Magdeburg,Germany.
authors.forename: M
authors.initials: M
authors.lastname: Walter
mesh_terms: D000328:Adult; D001931:Brain Mapping / Q000379:methods*; D003865:Major Depressive Disorder / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009415:Nerve Net / Q000503:physiopathology*; D017397:Prefrontal Cortex / Q000473:pathology* / Q000503:physiopathology