Effect Of High-Definition Transcranial Direct Current Stimulation On Patients With Consciousness Disorder Based On EEG Analysis

Disorder of consciousness(DOC)caused by severe brain injury is a difficult problem in clinical treatment.So far,there is no evidence-based guideline.Recent studies have suggested that Highdefinition transcranial direct current stimulation(HD-tDCS)has a positive effect on the recovery of consciousness,but the neural modulation mechanism of HD-TDCD efficacy needs to be verified by different analysis methods.At the same time,the method of EEG power spectrum combined with nonlinear dynamics has not been applied to evaluate the treatment of patients with disorder of consciousness by HD-tDCS.Therefore,in this study,27 patients with disorder of consciousness after long-term HD-tDCS treatment were involved.The scores of CRS-R and 32-channel resting state EEG before and after stimulation were tracked.The effects of long-term HD-tDCS patients with unconsciousness were analyzed and evaluated by power spectrum and nonlinear dynamic characteristic parameters from the whole brain to the specific brain area,from the stimulation area to the non-stimulation area.The results of this study are as follows:(1)During the treatment of HDtDCS in the precuneus,the relative power in the low frequency band decreased,the relative power in the high frequency band increased,and the approximate entropy,sample entropy,C0 complexity and LZ complexity also increased,indicating that the brain function of the patients was enhanced after treatment;(2)The results show that HD-tDCS not only occurs in the local area around the stimulation location,but also widely exists in the whole brain area;(3)HD-tDCS in the precuneus has a positive effect on the relative power and nonlinear characteristics of the power spectrum in the frontal,central,temporal and occipital regions of the patients with disorder of consciousness.In conclusion,longterm continuous HD-tDCS can promote the information processing among the neural groups of patients with consciousness disorders,which is expected to become a routine wake-up program for patients with consciousness disorders.