title: Frontal white matter anisotropy and symptom severity of late-life depression: a magnetic resonance diffusion tensor imaging study.
abstract: OBJECTIVE
  To investigate the disruption of neural circuits in the frontal lobes and limbic structures in late-life depressed patients compared with healthy controls, and to examine the correlation between the degree of microstructural abnormalities of white matter and clinical symptom severity in late-life depression.
  
  
  METHODS
  Thirteen patients with late-life depression and matched control subjects underwent diffusion tensor imaging. Fractional anisotropy (FA), an index of the integrity of white matter tracts, was determined in the white matter of frontal, temporal, and occipital brain regions and the corpus callosum.
  
  
  RESULTS
  A significant reduction was found in white matter FA values of widespread regions of the frontal and temporal lobes of depressed patients. Also, there was some evidence suggesting that white matter FA values of the inferior frontal brain region are inversely related to severity of depression.
  
  
  CONCLUSIONS
  These results suggest the possible loss of integrity within frontal and temporal white matter fibre tracts and implicate the orbitofrontal circuit in symptom severity in late-life depression.
authors.affiliation: Department of Neuropsychiatry, Kansai Medical University, Moriguchi, Japan. nobuhara@takii.kmu.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Nobuhara
authors.forename: G
authors.initials: G
authors.lastname: Okugawa
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
authors.forename: T
authors.initials: T
authors.lastname: Minami
authors.forename: C
authors.initials: C
authors.lastname: Tamagaki
authors.forename: K
authors.initials: K
authors.lastname: Takase
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: S
authors.initials: S
authors.lastname: Sawada
authors.forename: T
authors.initials: T
authors.lastname: Kinoshita
mesh_terms: D016880:Anisotropy; D000928:Antidepressive Agents / Q000627:therapeutic use; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology; D003865:Major Depressive Disorder / Q000188:drug therapy / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012720:Severity of Illness Index
chemical_list: D000928:Antidepressive Agents