The Study Of Transcranial Magnetic Stimulation And Electroencephalography In Disorder Of Consciousness

The rehabilitation of disorder of consciousness(DOC)is the concerned problem in today’s world.Accurate diagnostic results and effective treatment strategies are critical to the rehabilitation of patients with DOC.And the long-term rehabilitation of patients with DOC brings great pressure to the society and family.These problems have been plaguing clinicians and patients’ families.In order to solve these problems,people have carried out a lot of exploration.Among them,the technology of transcranial magnetic stimulation combined with electroencephalography(TMS-EEG)could measure cortical evoked activity,which had great potential in the evaluation of brain state and neural modulation effects.Repetitive transcranial magnetic stimulation(rTMS),as an effective means of neuromodulation,could modulate the excitability and inhibition of the cortex.In this paper,the active roles of transcranial magnetic stimulation and EEG in the diagnosis and neural modulation of DOC were studied based on analysis method of engineering signal and statistical method.The main achievements of this paper include:The design of the process of removing artifacts in TMS-EEG.Firstly,the paper introduced artifacts in TMS-EEG,which were divided into two classes including TMS evoked artifacts and artifacts induced by preprocessing.Secondly,it described the characteristics of artifacts and designed methods to remove them.For the particularity of EMG noise,it compared three methods to deal with TMS evoked muscle activity and determined the most suitable one.At last,it integrated all methods to design out the process of removing artifacts in TMS-EEG.TMS-EEG was applied to measure the awareness level of DOC,which used TMS evoked potentials(TEP)and the global mean field power(GMFP)as the feature to distinguish patients between vegetative state and minimally conscious state.The study results showed that TMS-EEG could be applied to the clinical diagnosis of DOC.A scheme of repetitive transcranial magnetic stimulation was designed and a clinical study was carried out.The evaluation scheme was designed,which consisted of the clinical scale CRS-R and TMS-EEG.The results of CRS-R found that different modulation results in patients between minimally conscious state(MCS)and vegetative state(VS),and the statistically signicicant differences.The results of TMS-EEG by calcutating TEP and GMFP found the signicicant changes of cortical excitability induced by rTMS in MCS,but no changes in VS.The correlation between the two methods proved that the changes of cortical excitability were related to the improvement of consciousness.The study has shown that TMS-EEG could be used as a tool to evaluate the modulation effects of rTMS on DOC.