Study Of Resting State EEG Microstate In Patients With Chronic Schizophrenia Treated With RTMs

Chronic schizophrenia has severe negative symptoms,which are usually resistant to antipsychotic drugs.In addition,almost one-third of positive schizophrenia patients also have medication-resistant symptoms,and thus novel adjuvant therapy is needed.Previous studies have shown that a non-invasive physical therapy of r TMS is a potential and effective adjunctive therapy for schizophrenia.r TMS with 10 Hz can improve the symptoms of schizophrenia,but unfortunately,the findings of 10 Hz r TMS in schizophrenia are inconsistent.In this study,a randomized,double-blind,controlled trial was designed.We collected the scores of positive and negative syndrome scales(PANSS)and resting state EEG data.The effects of 10 Hz r TMS on the improvements of positive and negative symptoms of chronic schizophrenia and the modulation of brain function activity were evaluated by an analysis of resting state EEG microstate.Sixty-six patients with chronic schizophrenia were recruited and randomly divided into the active group(33 patients)and the sham group(33 patients),who received 10 Hz r TMS active treatment and sham treatment for 4 weeks,5 times a week,1600 pulses each time,respectively.At baseline,post-treatment and three months after treatment(follow-up),the PANSS score was used to evaluate the positive and negative symptoms of all subjects.The resting state EEG of the subjects was also collected at baseline and post-treatment.After preprocessing,an analysis of resting state EEG microstate were performed.The analysis of PANSS score showed that after 10 Hz r TMS,there was a significant difference in the PANSS positive score within the group between post-treatment and baseline,between follow-up and baseline in the active group.In the analysis of PANSS positive score factor,delusion was significantly improved in the active group.There was no significant difference between the two groups in the PANSS positive score at the three time points,so was the PANSS negative score.There was no significant difference in the change of PANSS positive score among the three time points between the two groups,so was the changes of PANSS negative score.There were significant differences in delusion at follow-up between the two groups.In the subgroup analysis with negative symptoms as the dominant symptom,the above results were repeated.It was also found that after 10 Hz r TMS,the PANSS positive score of the sham group decreased significantly,but the significance was weaker than that of the active group.There were significant differences between the changes of the PANSS negative score between the post-treatment and the baseline,and between the changes of the PANSS negative score between the follow-up and the baseline.The reduction of the PANSS negative score of the sham group was greater than that of the active group.In the independent sample t-test,only the difference between follow-up and baseline was still significant.The analysis of resting state EEG microstate showed that the mean duration of class C microstate was significantly shorter in active group and the mean duration of class A microstate was significantly shorter in sham group.The changes of the mean duration of class D microstate between the post-treatment and the baseline showed a significant difference between the two groups.After 10 Hz r TMS,the mean duration of class D microstate in active group increased,while that of class D microstate in sham group is decreased.Partial correlation analysis showed that there was no significant correlation between the changes of mean duration of class D microstate and the changes of positive score or negative score in the active group and the sham group.In this study,our results showed that the effect of 10 Hz r TMS on the negative symptoms of chronic schizophrenia is weaker than that on the positive symptoms,and 10 Hz r TMS can modulation the damaged microstate of chronic schizophrenia to some extent.The analysis of resting state EEG microstate can be used to evaluate the efficacy of r TMS in schizophrenia,especially class C and D microstate,which has the potential to as an electrophysiological marker for efficacy evaluation.