title: Brain activation during executive processes in schizophrenia.
abstract: Schizophrenia patients show some deficits in executive processes (impaired behavioural performance and abnormal brain functioning). The aim of this study is to explore the brain activity of schizophrenia patients during different inhibitory tasks. We used functional magnetic resonance imaging to investigate to investigate the restraint and deletion aspects of inhibition in 19 patients with schizophrenia and 12 normal subjects during the performance of the Hayling and the N-back tasks. The patients demonstrated impaired performance (more errors and longer reaction times) in the Hayling task. Schizophrenia subjects activated the same fronto-parietal network as the control subjects but demonstrated stronger parietal activations. For the N-back task, the deficit shown by the patients was limited to the number of target omissions. The reaction times and the number of false alarms did not differ in the two groups. We interpret this pattern of deficit as an alteration of working memory processes (and unaltered inhibition). Schizophrenia subjects showed higher activations in a fronto-parietal network. Since schizophrenia patients reached normal inhibitory performances in the N-back task and not in the Hayling task, the frontal hyperactivation may reflect an increased effort or a compensatory mechanism that facilitates the performance of executive tasks. During the Hayling task, this frontal hyperactivation was not achieved, and its absence was associated with a performance deficit relative to the performance of normal subjects.
authors: Department of Psychiatry, University Hospital of Bellevue, Saint-Etienne, France.
authors: Aurélie
authors: A
authors: Royer
authors: Fabien Christian Georges
authors: FC
authors: Schneider
authors: Anne
authors: A
authors: Grosselin
authors: Jacques
authors: J
authors: Pellet
authors: Fabrice-Guy
authors: FG
authors: Barral
authors: Bernard
authors: B
authors: Laurent
authors: Denis
authors: D
authors: Brouillet
authors: François
authors: F
authors: Lang
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000503:physiopathology*; D001931:Brain Mapping; D003072:Cognition Disorders / Q000209:etiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011340:Problem Solving / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012559:Schizophrenia / Q000150:complications* / Q000473:pathology; D012565:Schizophrenic Psychology; D055815:Young Adult
chemical_list: D010100:Oxygen