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The goal of the study was to investigate cerebral blood flow (CBF) and its connectivity (an across-subject covariance measure) patterns of schizophrenia (SZ) patients with auditory verbal hallucinations (AVHs). A total of demographically matched 25 SZ patients with AVHs, 25 without AVHs, and 25 healthy controls (HCs) underwent resting state perfusion imaging using a pulsed arterial spin labeling sequence. CBF and its connectivity were analyzed and then CBF topological properties were calculated. AVHs patients exhibited decreased CBF in the bilateral superior and middle frontal gyri and postcentral gyri, and right supplementary motor area compared with SZ patients without AVHs. SZ patients without AVHs showed reduced CBF in the left middle frontal gyrus relative to HCs. Moreover, AVHs groups showed distinct connectivity pattern, an intermediate level between HCs and patients without AVHs in the global efficiency. Our study demonstrates aberrant CBF in the brain regions associated with inner speech monitoring and language processing in SZ patients with AVHs. The complex network measures showed by CBF-derived functional connectivity indicate dysconnectivity between different functional units within the network of AVHs in SZ. Our findings might shed light on the neural underpinnings behind AVHs in this devastating disease at the level of CBF and its connectivity. [ABSTRACT FROM AUTHOR]

Heterogeneous findings across studies of structural abnormality in schizophrenia (SZ) have impeded the development a unified theory of white matter pathology. As a cardinal symptom of SZ, auditory verbal hallucination (AVH) has been suspected to be associated with improper communication among several brain regions, which might indicated white matter pathology. Participants comprised 25 first-episode (FE) patients with AVH, 25 patients without AVH and 25 healthy subjects. Diffusion tensor imaging (DTI) measures were calculated using the TBSS of FSL. Voxel-based ANOVA tests were performed among the three groups and threshold-free cluster enhancement (TFCE) method correction was used for multiple comparisons. Voxel-based one-way ANOVA showed significant group effects for fractional anisotropy (FA) and radial diffusivity (RD) values. Post-hoc t -tests indicated that schizophrenia patients had lower FA and higher RD values in the internal capsule and anterior corona radiata than control subjects. Post-hoc analyses exhibited more widespread fiber disruptions in AVH patients than non-AVH patients. These results hinted on the important role of projection fiber disruption in schizophrenia patients. In addition, the current study also suggested that direct comparison between studies using patients with different symptom profiles should be interpreted with caution. [ABSTRACT FROM AUTHOR]