title: Verbal memory impairment in new onset bipolar disorder: Relationship with frontal and medial temporal morphology.
abstract: OBJECTIVE
  Verbal memory (VM) impairment is a trait feature of bipolar I disorder (BDI) that is present at illness onset and associated with functional outcome. However, little is known about the morphological abnormalities underlying this deficit early in the disease course. This study examined the neurobiological correlates of VM impairment in euthymic newly diagnosed patients, with attention to frontal and medial temporal (MT) structures known to contribute to VM.
  
  
  METHODS
  Euthymic patients with BDI recently recovered from their first episode of mania (n = 42) were compared with healthy subjects (n = 37) using measures of the California Verbal Learning Test (CVLT-II) associated with frontal and MT functioning. A subset of participants had 3T MRI scan (n = 31 patient group, n = 30 healthy subject group). Hippocampal and prefrontal volumes were analyzed using FreeSurfer 5.1 and correlated with their corresponding CVLT-II subscores.
  
  
  RESULTS
  Patients showed decreased performance in total learning as well as short and long delay verbal recall. Consistent with MT dysfunction, they also showed deficits in recognition discriminability and learning slope. In the patient group only, left hippocampal volumes were negatively correlated with these measures.
  
  
  CONCLUSIONS
  These results suggest that anomalous MT functioning is involved with VM impairment early in the course of BDI.
authors.affiliation: Department of Psychiatry, University of British Columbia , Vancouver, BC , Canada.
authors.forename: Trisha
authors.initials: T
authors.lastname: Chakrabarty
authors.forename: Jan-Marie
authors.initials: JM
authors.lastname: Kozicky
authors.forename: Ivan J
authors.initials: IJ
authors.lastname: Torres
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Lam
authors.forename: Lakshmi N
authors.initials: LN
authors.lastname: Yatham
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D001714:Bipolar Disorder / Q000175:diagnosis*; D016022:Case-Control Studies; D005260:Female; D006624:Hippocampus / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000503:physiopathology*; D009483:Neuropsychological Tests; D014706:Verbal Learning; D055815:Young Adult
keywords: MRI; bipolar I disorder; hippocampus; neuropsychological tests; verbal memory