title: Frontal white matter alterations are associated with executive cognitive function in euthymic bipolar patients.
abstract: BACKGROUND
  Bipolar affective disorder (BD) is often associated with cognitive dysfunction in executive domains. However the biological underpinnings of cognitive deficits in BD are not sufficiently understood. A growing body of evidence indicates a loss of microstructural integrity in various white matter (WM) fiber tracts in BD. The aim of the current study was to assess potential links between WM structural abnormalities and cognitive performance in euthymic middle-aged BD patients (n=30) and matched healthy controls (n=32).
  
  
  METHODS
  Diffusion tensor imaging (DTI) data was carried out with both voxelwise (tract based spatial statistics, TBSS) and region-of-interest (ROI) based analysis. We compared multiple indices of diffusion including fractional anisotropy (FA), radial (DR), axial (DA) and mean diffusivities (MD).
  
  
  RESULTS
  Increased mean diffusivity was found in the fornix, anterior thalamic radiation, splenium and the truncus of the corpus callosum in BD patients compared with controls. These diffusion changes were significantly associated with poorer performance in executive tasks in BD patients.
  
  
  CONCLUSIONS
  Our results indicate a direct link between executive cognitive functioning and abnormal WM microstructural integrity of fronto-limbic tracts in remitted BD patients, and add evidence to the neuronal disruption that underlies the residual symptomatology of BD.
authors.affiliation: Laboratory of Neurophysiology and Neuroimaging, Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University, Frankfurt/Main 60528, Germany. Electronic address: Viola.Oertel@kgu.de.
authors.forename: Viola
authors.initials: V
authors.lastname: Oertel-Knöchel
authors.affiliation: Laboratory of Neurophysiology and Neuroimaging, Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University, Frankfurt/Main 60528, Germany.
authors.forename: Britta
authors.initials: B
authors.lastname: Reinke
authors.affiliation: Center for Alzheimer's Disease and Related Disorders, Universidade Federal, do Rio de Janeiro, Brazil.
authors.forename: Gilberto
authors.initials: G
authors.lastname: Alves
authors.affiliation: Institute for Neuroradiology, Goethe University, Frankfurt/Main, Germany; Center for Individual Development and Adaptive Education of Children at Risk, Frankfurt, Germany.
authors.forename: Alina
authors.initials: A
authors.lastname: Jurcoane
authors.affiliation: Laboratory of Neurophysiology and Neuroimaging, Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University, Frankfurt/Main 60528, Germany.
authors.forename: Sofia
authors.initials: S
authors.lastname: Wenzler
authors.affiliation: Laboratory of Neurophysiology and Neuroimaging, Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University, Frankfurt/Main 60528, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Prvulovic
authors.affiliation: MRC Centre for Neuropsychiatric Genetics & Genomics, Institute of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, CF, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Linden
authors.affiliation: Laboratory of Neurophysiology and Neuroimaging, Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University, Frankfurt/Main 60528, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Knöchel
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000503:physiopathology*; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology*; D056324:Diffusion Tensor Imaging; D056344:Executive Function / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009413:Nerve Fibers, Myelinated / Q000473:pathology*
keywords: Bipolar disorders; Cognition; DTI; ROI-analysis; VBM