title: Treatment with olanzapine is associated with modulation of the default mode network in patients with Schizophrenia.
abstract: Earlier studies have shown widespread alterations of functional connectivity of various brain networks in schizophrenia, including the default mode network (DMN). The DMN has also an important role in the performance of cognitive tasks. Furthermore, treatment with second-generation antipsychotic drugs may ameliorate to some degree working memory (WM) deficits and related brain activity. The aim of this study was to evaluate the effects of treatment with olanzapine monotherapy on functional connectivity among brain regions of the DMN during WM. Seventeen patients underwent an 8-week prospective study and completed two functional magnetic resonance imaging (fMRI) scans at 4 and 8 weeks of treatment during the performance of the N-back WM task. To control for potential repetition effects, 19 healthy controls also underwent two fMRI scans at a similar time interval. We used spatial group-independent component analysis (ICA) to analyze fMRI data. Relative to controls, patients with schizophrenia had reduced connectivity strength within the DMN in posterior cingulate, whereas it was greater in precuneus and inferior parietal lobule. Treatment with olanzapine was associated with increases in DMN connectivity with ventromedial prefrontal cortex, but not in posterior regions of DMN. These results suggest that treatment with olanzapine is associated with the modulation of DMN connectivity in schizophrenia. In addition, our findings suggest critical functional differences in the regions of DMN.
authors: Psychiatric Neuroscience Group, Department of Neurological and Psychiatric Sciences, University of Bari, Bari, Italy.
authors: Fabio
authors: F
authors: Sambataro
authors: Giuseppe
authors: G
authors: Blasi
authors: Leonardo
authors: L
authors: Fazio
authors: Grazia
authors: G
authors: Caforio
authors: Paolo
authors: P
authors: Taurisano
authors: Raffaella
authors: R
authors: Romano
authors: Annabella
authors: A
authors: Di Giorgio
authors: Barbara
authors: B
authors: Gelao
authors: Luciana
authors: L
authors: Lo Bianco
authors: Apostolos
authors: A
authors: Papazacharias
authors: Teresa
authors: T
authors: Popolizio
authors: Marcello
authors: M
authors: Nardini
authors: Alessandro
authors: A
authors: Bertolino
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001569:Benzodiazepines / Q000494:pharmacology / Q000627:therapeutic use*; D001921:Brain / Q000098:blood supply / Q000187:drug effects; D001931:Brain Mapping; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008569:Memory Disorders / Q000188:drug therapy / Q000209:etiology / Q000473:pathology; D008570:Memory, Short-Term / Q000187:drug effects; D009415:Nerve Net / Q000098:blood supply / Q000187:drug effects; D009483:Neuropsychological Tests; D000077152:Olanzapine; D010100:Oxygen / Q000097:blood; D025341:Principal Component Analysis / Q000379:methods; D011446:Prospective Studies; D012559:Schizophrenia / Q000150:complications* / Q000188:drug therapy / Q000473:pathology; D013997:Time Factors; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D001569:Benzodiazepines; D000077152:Olanzapine; D010100:Oxygen