Longitudinal Study Of First Episode Schizophrenia Patients Using Multimodal Magnetic Resonance Imaging

Altered functional network organization and abnormal brain metabolism have been shown in schizophrenia.The brain regions showing functional and metabolic alterations include the dorsolateral prefrontal cortex(DLPFC),ventromedial prefrontal cortex(vmPFC),the frontoparietal network(FPN)and the default mode network(DMN).Moreover,emerging evidence has shown that the functional-metabolic coupling could affect the development and recovery of schizophrenia.The aim of this study is to investigate the functional-metabolic coupling in first-episode schizophrenia(FES)patients,and analyze the longitudinal changes after antipsychotic medication treatment.In this study,31 first-episode schizophrenia patients and 28 matched healthy controls(HCs)enrolled.We acquired resting-state functional magnetic resonance imaging(rs-fMRI)and proton magnetic resonance spectroscopy(~1H-MRS)data at baseline,2(V1)and 6 months(V2)for patients group and baseline data for healthy controls.We explored the functional alterations including the functional connectivity from vmPFC and functional modular features of FPN and DMN using rs-fMRI.Moreover,we obtained the ~1H-MRS data from DLPFC and vmPFC as the regions-of-interest.Two sample t test and repeated measures analysis of variance(RMANOVA)analysis were used to assess the group difference and longitudinal changes.Furthermore,the partial correlation analysis was performed to investigate the coupling between altered modular functional connectivity and metabolic concentrations.Finally,the correlations with schizophrenia symptomatology were also investigated by partial correlation analysis.The hyper-connectivities were observed including the intra-module connectivity within frontoparietal module and the inter-module connectivity between DMN and subcortical module in FES groups.In FES group,the GABA level in vmPFC decreased significantly at V1 stage and rose at V2stage.Furthermore,the GABA concentration at baseline was positively correlated with the clinical symptom,especially the positive and excitement symptoms.In addition,the GABA level was positively correlated with intra-modular strength within DMN module in HC group,while the FES group showed an opposite correlation pattern.The longitudinal study of functional-metabolic coupling in FES showed that the altered modular functional-metabolic coupling might underlie the etiology of schizophrenia.Our findings added insights into the pathophysiology of schizophrenia.