The global efficiency of the brain structural networks and its relationship with the psychotic symptoms in male paranoid schizophrenia

Abstract

Objective To explore the differences of the global efficiency of the brain structural networks between the male paranoid schizophrenia and male healthy and its relationship with the psychotic symptoms of the schizophrenia. Methods The diffusion tensor imaging data were obtained from 27 male paranoid schizophrenia patients and 28 male healthy controls. The whole cerebral cortex was parcellated into 90 regions by the anatomical label map. Tractography was performed in the whole cerebral cortex of each subject to reconstruct white matter tracts of the brain using fiber assignment by continuous tracking(FACT) algorithm. And then the brain structural binary networks were constructed using the complex network theory. The average global efficiency of the brain network and the global efficiency of the nodes of both groups were examined by two sample t-test and its relationship with the psychotic symptoms in the male paranoid schizophrenia was explored by the correlation analysis. Results Compared with control group, the average global efficiency of the brain network of the patients decreased significantly (7.87±0.56, 8.17±0.56, P=0.005), and the global efficiency of the nodes in the brain network of the patient decreased significantly in the left superior frontal gyrus (orbital part) (P=0.00025), the left superior parietal gyrus (P=0.00011), the left cuneus (P=0.00012) and the left putamen (P=0.00032), all survived FDR correction. Significant negative correlation was found between the global efficiency of the left putamen and the total scores (r=-0.43, P=0.03), the positive scores (r=-0.41, P=0.03) and the cognitive scores (r=-0.40, P=0.04) of PANSS. Conclusion The decreased global efficiency of the left frontal, parietal and occipital lobes and the subcortical structures lead to the occurrence of schizophrenia. And the reduced efficiency of the subcortical structures is associated with the positive symptoms and the abnormal cognitive function of the patients. Key words: Paranoid schizophrenia; Diffusion tensor imaging; Brain structural network; Global efficiency; Psychotic symptoms