title: Cognitive performances associate with measures of white matter integrity in bipolar disorder.
abstract: BACKGROUND
  Neuropsychological deficits constitute enduring trait-like features in bipolar disorder (BD), and persist in euthymia. White matter (WM) abnormalities are one of the most consistently reported findings in neuroimaging studies of BD. We hypothesized that neuropsychological performances could correlate with WM integrity in a sample of bipolar patients in core WM tracts.
  
  
  METHODS
  Seventy-eight patients affected by BD were evaluated for verbal memory, working memory, psychomotor coordination, executive functions, attention and information processing, and verbal fluency through the Brief Assessment of Cognition in Schizophrenia. White matter integrity was evaluated using DTI and tract-based spatial statistics with threshold free cluster enhancement (p>0.949).
  
  
  RESULTS
  We observed that cognitive performances in attention and information processing, working memory, executive functions and psychomotor coordination were associated with DTI measures of WM integrity in several association fibres: inferior and superior longitudinal fasciculus, inferior fronto-occipital fasciculus, cingulum bundle, corpus callosum, and corona radiata.
  
  
  CONCLUSIONS
  The drug treatments administered during the course of the illness could have influenced DTI measures and neurocognitive function. Other limitations include issues such as generalizability due to the lack of a control group, possible undetected past comorbidities, population stratification, and the presence of a 28% of patients which previously experienced delusions.
  
  
  CONCLUSIONS
  This is the first study to use a validated cognitive battery to investigate the principal cognitive domains in BD. Our data confirm the importance of WM integrity as a neurobiological underpinning of cognitive deficits.
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy. Electronic address: poletti.sara@hsr.it.
authors.forename: Sara
authors.initials: S
authors.lastname: Poletti
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Bollettini
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Mazza
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Clara
authors.initials: C
authors.lastname: Locatelli
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Radaelli
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Benedetta
authors.initials: B
authors.lastname: Vai
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Smeraldi
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Colombo
authors.affiliation: Scientific Institute and University Vita-Salute San Raffaele, Department of Clinical Neurosciences, Via Stamira d׳Ancona 20, San Raffaele Turro Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Benedetti
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000473:pathology* / Q000523:psychology*; D003071:Cognition; D060825:Cognitive Dysfunction / Q000473:pathology* / Q000523:psychology*; D003337:Corpus Callosum / Q000473:pathology; D056344:Executive Function; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D009415:Nerve Net / Q000473:pathology; D059906:Neuroimaging; D011597:Psychomotor Performance; D012559:Schizophrenia / Q000473:pathology; D012565:Schizophrenic Psychology; D066127:White Matter / Q000473:pathology*
keywords: Bipolar disorder; Executive functions; Information processing; Psychomotor coordination; White matter integrity; Working memory