Article

White matter tract abnormalities between rostral middle frontal gyrus, inferior frontal gyrus and stratum in first episode schizophrenia

Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
Schizophrenia Research (Impact Factor: 3.92). 04/2013; 145(1-3):1-10. DOI: 10.1016/j.schres.2012.11.028
Source: PubMed

ABSTRACT

Previous studies have shown that frontostriatal networks, especially those involving dorsolateral prefrontal cortex (DLPFC) and ventrolateral prefrontal cortex (VLPFC) mediate cognitive functions some of which are abnormal in schizophrenia. This study examines white matter integrity of the tracts connecting DLPFC/VLPFC and striatum in patients with first-episode schizophrenia (FESZ), and their associations with cognitive and clinical correlates.
Diffusion tensor and structural magnetic resonance images were acquired on a 3T GE Echospeed system from 16 FESZ and 18 demographically comparable healthy controls. FreeSurfer software was used to parcellate regions of interest. Two-tensor tractography was applied to extract fibers connecting striatum with rostral middle frontal gyrus (rMFG) and inferior frontal gyrus (IFG), representing DLPFC and VLPFC respectively. DTI indices, including fractional anisotropy (FA), trace, axial diffusivity (AD) and radial diffusivity (RD), were used for group comparisons. Additionally, correlations were evaluated between these diffusion indices and the Wisconsin Card Sorting Task (WCST) and the Brief Psychiatric Rating Scale (BPRS).
FA was significantly reduced in the left IFG-striatum tract, whereas trace and RD were significantly increased in rMFG-striatum and IFG-striatum tracts, bilaterally. The number of WCST categories completed correlated positively with FA of the right rMFG-striatum tract, and negatively with trace and RD of right rMFG-striatum and right IFG-striatum tracts in FESZ. The BPRS scores did not correlate with these indices.
These data suggest that white matter tract abnormalities between rMFG/IFG and striatum are present in FESZ and appear to be significantly associated with executive dysfunction but not with symptom severity.

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    • "renia , providing important information about tracts and connectivity ( see ' Connectivity and myelination ' ) . These studies have reported decreases in anisotropy , particularly in the left frontal ( Jeong et al . , 2009 ; Mitelman et al . , 2009 ; Spoletini et al . , 2009 ; Walther et al . , 2011 ; Henze et al . , 2012 ; Nazeri et al . , 2013 ; Quan et al . , 2013 ) and temporal ( Friedman et al . , 2008 ; Hoptman et al . , 2008 ; Rametti et al . , 2009 ; Phillips et al . , 2011 ; Kitis et al . , 2012 ) lobes . DTI investigations in gray matter in schizophrenia have reported increased diffusivity in the superior temporal gyrus , parahippocampal gyrus and insula , but no change in anisotropy from "
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    Full-text · Article · Feb 2015 · Schizophrenia Research
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