A comparative study of the effect of a single transcranial direct current stimulation on resting state of brain functional network in patients in a minimally conscious state / 中华物理医学与康复杂志

ABSTRACT

Objective To investigate the effect of transcranial direct current stimulation (tDCS) on the amplitude of low-frequency fluctuation (ALFF) of the resting brain function network in patients in a minimal conscious state (MCS) so as to explore the mechanism.Methods Eleven MCS patients were selected.Among them,there were 9 males and 2 females,10 with cerebral trauma and 1 with cerebral hemorrhage,with an average age of (37.3±8.4) and an average course of disease of (3.4±0.1) months.All subjects were given a resting-state functional magnetic resonance imaging (rs-fMRI) assessment prior to the single tDCS treatment,followed by a 20-minute single sham tDCS treatment at a time.After single-sham stimulation,a second time rs-fMRI assessment test will be conducted,followed by a real tDCS treatment for 20 minutes.Eventually,a third time rs-fMRI assessment test will be implemented.Results No significant statistical difference was shown in terms of all the parameters after single shamtDCS as compared to those before the treatment (P＞0.05).After single real-tDCS,no significant change was observed with CRS-R score,ALFF of default network (left anterior wedge),the frontal-parietal network (left fróntal lobe,right superior gyms),sensory motor network (left auxiliary motor area),subcortical network (right thalamus,bilateral caudate nuclei) was significantly higher than that before treatment,while the ALFF of the frontal network (frontal lobe) and auditory network (bilateral temporal lobes) was significantly decreased (P＜0.05).After single real-tDCS,the ALFF of default network (right frontal lobe) was significantly enhanced compared to that after single sham-tDCS (P＜0.05),while that of the salient network (left insula) and sensorimotor network (right central frontal) was significantly decreased (P＜0.05).Conclusion The enhancement of ALFF activity in the resting state brain function network is a possible neural mechanism for tDCS to promote the recovery of consciousness level in pa tients with minimal conscious state.