Aberrant Connectivity Between Salience Network And Central Executive Network In Schizophrenia

The function of human brain is based on the combined action of brain networks. Studies show that networks related to language, vision and cognition have changed in schizophrenia patients. Salience network (SN) contributes to delusion and auditory hallucination. Impairment of working memory, attention and task management has a close relationship with central executive network (CEN). SN is known for its critical role in switching CEN and default-mode network (DMN) during cognitively demanding tasks, which has been reported to be aberrant in schizophrenia. However, there are few direct evidences about the aberrant alteration of connectivity between the two networks. Moreover, studies have merely investigated the structural mechanism underlying the change between SN and CEN.The current study aimed to investigate the change between SN and CEN in schizophrenia by combining functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI).22 schizophrenia patients (disease duration> 2 years) and 21 healthy controls were recruited. The joint use of tract-based spatial statistics (TBSS) and region of interest based segmentation were applied to investigate the integrity of white matter. Based on correlation analysis of rs-fMRI data, functional connectivity in SN-CEN circuit was calculated. Moreover, the study investigated relationship between structural and functional connectivity.The results show that schizophrenia patients had lower fractional anisotropy (FA) in inferior long fasciculus (ILF, right), callosal body and inferior fronto-occipital fasciculus (IFOF, left) than healthy controls. Significantly reduced functional connectivity was also found between right fronto-insular cortex (rFIC) and right posterior parietal cortex (rPPC). FA in right ILF was positively correlated with the functional connectivity of rFIC-rPPC. Therefore, we proposed a disruption of structural and functional connectivity in SN-CEN circuit in schizophrenia. And the decreased integrity of ILF could be the cause of aberrant functional connectivity between the two networks, which might account for a core feature of schizophrenia.