title: Structural and Functional Brain Correlates of Cognitive Impairment in Euthymic Patients with Bipolar Disorder.
abstract: BACKGROUND
  Cognitive impairment in the euthymic phase is a well-established finding in bipolar disorder. However, its brain structural and/or functional correlates are uncertain.
  
  
  METHODS
  Thirty-three euthymic bipolar patients with preserved memory and executive function and 28 euthymic bipolar patients with significant memory and/or executive impairment, as defined using two test batteries, the Rivermead Behavioural Memory Test (RBMT) and the Behavioural Assessment of the Dysexecutive Syndrome (BADS), plus 28 healthy controls underwent structural MRI using voxel-based morphometry (VBM). Twenty-seven of the cognitively preserved patients, 23 of the cognitively impaired patients and 28 controls also underwent fMRI during performance of the n-back working memory task.
  
  
  RESULTS
  No clusters of grey or white matter volume difference were found between the two patient groups. During n-back performance, the cognitively impaired patients showed hypoactivation compared to the cognitively preserved patients in a circumscribed region in the right dorsolateral prefrontal cortex. Both patient groups showed failure of de-activation in the medial frontal cortex compared to the healthy controls.
  
  
  CONCLUSIONS
  Cognitive impairment in euthymic bipolar patients appears from this study to be unrelated to structural brain abnormality, but there was some evidence for an association with altered prefrontal function.
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.|Programa de Doctorado de Medicina, University of Barcelona, Barcelona, Spain.
authors.forename: Silvia
authors.identifier: http://orcid.org/0000-0002-3063-6929
authors.initials: S
authors.lastname: Alonso-Lana
authors.affiliation: Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.|Bipolar Disorder Program, Institute of Neuroscience, Hospital Clínic, University of Barcelona, IDIBAPS, Barcelona, Catalonia, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Goikolea
authors.affiliation: Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.|Bipolar Disorder Program, Institute of Neuroscience, Hospital Clínic, University of Barcelona, IDIBAPS, Barcelona, Catalonia, Spain.
authors.forename: Caterina M
authors.initials: CM
authors.lastname: Bonnin
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Salvador
authors.initials: S
authors.lastname: Sarró
authors.affiliation: Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain.
authors.forename: Barbara
authors.initials: B
authors.lastname: Segura
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Benedikt L
authors.initials: BL
authors.lastname: Amann
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Gemma C
authors.initials: GC
authors.lastname: Monté
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Benito Menni Complex Assistencial en Salut Mental, Barcelona, Spain.
authors.forename: Noemi
authors.initials: N
authors.lastname: Moro
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Benito Menni Complex Assistencial en Salut Mental, Barcelona, Spain.
authors.forename: Paloma
authors.initials: P
authors.lastname: Fernandez-Corcuera
authors.affiliation: Hospital Sant Joan de Déu Infantil, Barcelona, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Maristany
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Raymond
authors.initials: R
authors.lastname: Salvador
authors.affiliation: Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.|Bipolar Disorder Program, Institute of Neuroscience, Hospital Clínic, University of Barcelona, IDIBAPS, Barcelona, Catalonia, Spain.|Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain.
authors.forename: Eduard
authors.initials: E
authors.lastname: Vieta
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Edith
authors.initials: E
authors.lastname: Pomarol-Clotet
authors.affiliation: FIDMAG Germanes Hospitalàries Research Foundation, Barcelona, Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: McKenna
mesh_terms: D000328:Adult; D000339:Affect; D001714:Bipolar Disorder / Q000473:pathology / Q000503:physiopathology*; D060825:Cognitive Dysfunction / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged