Investigated The Underlying Mechanism Of Auditory Verbal Hallucinations Based On Big Data Of FMRI And DTI From Mulit-sites

Schizophrenia is a serious disorder,auditory verbal hallucinations（AVHs）is one of the most common positive symptoms of schizophrenia^[3].In last two decades,the fast adventure of neuroimaging techniques have helped researchers discovered more and more evidences of the underlying mechanism of AVHs,though there is not a clear conclusion.In this thesis,we will investigat the abnormal functional and structural connectivities within auditory network（AN）based on big data from 7 sites.We applied779 controls in total,there are 193 schizophrenias with AVHs（AVH）,267schizophrenias without AVHs（nAVH）,and 319 normal controls（NC）.The thesis includes 2 parts,in the first one we discovered the altered functional connectivities within AN,and in the part two,we researched the abnormal functional and structural connectivities between medial geniculate body and whole brain.To determine the functional roles of the AN in schizophrenia with auditory verbal hallucinations,we used resting-state functional magnetic resonance imaging（fMRI）to identify the alterations that are specifically associated with the onset of AVHs.We first used a coordinate-based meta-analysis to define the AN and applied the Brainnetome atlas to identify the corresponding anatomical areas.Next,we measured the resting-state functional connectivity（RSFC）in the AN in controls from 7 different sites.The statistical analyses revealed significantly decreased RSFC between the left Heschl’s gyrus（TE1.0/TE1.2）and the right primary somatosensory cortex（A1/2/3ton La,Brodmann area 1/2/3（tongue and larynx region））in the AVH patients compared to the nAVH patients or the NC.Moreover,the statistical analyses were performed separately for each site and the results of all seven sites were integrated using a multi-center approach.The alteration identified using this approach was the same as that identified above.The statistical results were consistent for all the sites separately and also showed great consistency when all the sites were considered as a whole.Finally,correlation analyses were performed,and a significant negative correlation between the RSFC between the left TE1.0/TE1.2 and the right A1/2/3tonLa and the Auditory Hallucination Rating Scale（AHRS）was found in AVH.Our findings showed abnormality in the RSFC between the left TE1.0/TE1.2 and the right A1/2/3tonLa and a negative correlation between that alteration and the AHRS.In the second research,at first,we applied the identification of MGB from Devlin and his colleagues,then the RSFC and probabilistic tractography were calculated between MGB and whole brain based on Brainnetome Atlas and AAL,after the statistics analysis we found that the RSFC between left MGB and right postcentral and the RSFCs between right MGB and right inferior parietal lobule,left/right precuneus and left/right postcentral in AVH were significantly decreased compared to nAVH and NC.The structural connectivity probability between left MGB and left heschl’s gyrus and the probability between right MGB and right heschl’s gyrus and right precuneus in the AVH were significantly decreased compared to nAVH and NC.Take all together,we suggest a hypothesis when inner speech was happened the abnormal prediction modal caused by altered functional connectivity between left heschl’s gyrus and right A1/2/3ton La was the underlying mechanism that confused the AVH,and AVH feel the‘real sound’.As we already know that the interaction of auditory and somatosensory is based on MGB,the functional and structural connectivity between MGB with Heschl’s gyrus and postcentral may strengthen the hypothesis.These findings may facilitate the understanding of the underlying mechanism of AVHs and provide a potential neurobiological marker for early diagnosis.