Research On The Microstate Properties And Correlation Of The MEG Of Depression Patients

Depression,as a kind of emotional disease,has complex pathogenesis.Depression patients show a sad mood,and even choose to commit suicide.Magnetoencephalogram,as a non-invasive and non-invasive technique,has gradually been used in the study of depression due to its high temporal and spatial resolution.This paper studies the properties and correlations of MEG microstate sequences of EMG signals of 6 depression patients and 9 healthy subjects.The research of this paper consists of the following three parts.Firstly,in the analysis of the microstate properties of MEG singals,it was found that the effect was best when the modified KMeans algorithm was used and the number of clusters was 4.The results of the microstate experiments show that the difference between the depression patient group and the healthy control group is significant in the central and frontal areas,which is that the entropy of the depression patient group is significantly greater than that of the healthy control group under negative emotional picture stimulation,and the entropy rate of the depression patient group was greater than that of the healthy control group under positive,neutral and negative emotional picture stimulation,which indicates that the disorder degree of MEG in the depression patient group is higher than that in the healthy control group,and the change rate of disorder degree in the depression patient group is higher than that in the healthy control group under the stimulation of three different emotional pictures.In addition,we found that the microstate sequences of the depression patient group in the combination healthy control group rejected the low-order Markov hypothesis and accepted the symmetry hypothesis,but the healthy control group accepted the stability hypothesis under the negative emotional picture stimulation,while the depression patient group rejected the stability hypothesis under different stimulation.Secondly,in the correlation study of MEG,time-lagged mutual information was used as the criterion of assessing correlation.The results of time-lagged mutual information show that the time-lagged mutual information of the depression patients group in the frontal and central regions was much lower than that of the healthy control group under neutral emotional picture stimulation,indicating that the correlation of depression depreddion patient group in central and frontal region is smaller than that of the healthy control group.In addition,we found that under the stimulation of neutral and negative emotional pictures,the time-lagged mutual information in the healthy control group decreased faster than that in the depression group,while the opposite of the positive emotional pictures stimulated them,this may be related to the fact that the depression patient are not sensitive to the stimulation of positive emotional pictures.Thirdly,in the long-range correlation study of the MEG,the Hurst exponent was used as the criterion for assessing the long-range correlation.The results of the long-range correlation experiment show that the Hurst exponent of depression patient group and healthy control group were greater than 0.5,indicating that they have long-range correlations and show persistent characteristics.Stimulated by neutral mood pictures,the healthy control group's sustained intensity in the central area,frontal area,and their left and right region was greater than that of depression patient group.In addition,it was found that under the stimulation of different emotional pictures,the persistence intensity of depression patient group in the left and right region of the central area and the frontal area has a clear strength relationship,while the healthy control group has no distinction.After comparing the microstate properties and correlations of the MEG of depression patients and healthy control group,it was found that the difference between the central and frontal regions is obvious,and the most significance is stimulated by neutral emotional pictures.It shows that the study of the microstate properties and correlations based on MEG can better distinguish between depression patient group and healthy control group,and can provide a reference for the clinical diagnosis of depression.