Application Of ALFF And Brain Connections Methods In Brain Imaging Data Analysis

The human brain is a highly complex system consisting of 100 billion neurons,the realization of a function of the brain,it is generally believed to be dependent on the synergy of multiple brain regions or the specific role of a certain brain region.In the previous study of mental illness,most of the results are concentrated in the brain or brain connections abnormal,this also happens to reflect the mechanism of the realization of brain function.The purpose of this study is to study the pathogenesis of schizophrenic patients,the connection between abnormal brain area and abnormal brain was analyzed.This article has the following three main tasks:(1)Study of abnormal brain region and analysis of functional connection:First use of amplitude of low-frequency fluctuation analysis method,study of brain functional magnetic resonance imaging data in 44 schizophrenic patients and 33 normal controls,calculate the average amplitude intensity of each BOLD signal in the 0.01HZ-0.08HZ band of each brain,and the statistical method is used to analyze the differences between the two groups of subjects.The result was found,the abnormal brain areas of the patients were mainly located in the frontal,temporal,occipital,parietal,cingulate,and thalamus,and many brain regions are located in the frontal lobe.Then the correlation analysis based on seed point is used to analyze the functional connection.The three brain regionswith the largest number of ALFF abnormal voxels were selected:The leftmiddle frontal gyrus,the right complement movement area,the left top upper gyrus as the region of interest(ROI),using Pearson correlation to construct the functional connection network of the three brain regions to the whole brain respectively,through statistical analysis,it was found that the brain areas with abnormal functional connectivity were distributed in the frontal,temporal,parietal,and occipital lobes,and many brain regions are located in the frontal lobe.(2)Granger causality analysis:Effect connection analysis can depict the flow of information in the brain,more meaningful than functional analysis,Granger causality analysis is based on the prediction error between variables to carry out effect connection analysis.The left middle frontal gyrus,right supplementary motor area,left superior parietal gyrus,right middle frontal gyrus,left middle occipital gyrus,left praecuneus,right angular gyrus,left supplementary motor area,left middle temporal gyrus and left lateral superior frontal gyrus were used as ROI,then Granger causality analysis was used to analyze the abnormal effect connection of patients.The results showed that there was a significant difference between the left middle frontal gyrus and the upper lateral frontal gyrus of the left side of the patient with a two-way effect connection,while the normal person did not exist.(3)Liang-Keeman information flow causality analysis:This method is also used to analyze effect connections,whether the change of the marginal entropy of the variable is affected by other variables to analyze the effect connection,it portrays the transfer of information between variables,so it is a more direct reflection of the causality.The application of this method to the left middle frontal gyrus,right supplementary motor area,left parietal gyrus,right middle frontal gyrus,left middle occipital gyrus,,left precuneus,right angular gyrus and left supplementary motor area,middle temporal gyrus,left dorsolateral frontal gyrus in these ten areas of the brain are connected effect analysis.lt is found that the results obtained here are in agreement with the results obtained by the Granger causality analysis,the role of mutual validation.This paper analyses the three different angles of the abnormal brain area,functional connection and effect connection,it is more helpful to help us discover the pathogenesis of schizophrenia.