多靶区经颅直流电刺激对健康成年人工作记忆-姿势控制双任务表现的影响

Effect of multi-target transcranial direct current stimulation on performance of working memory-postural control dual-task in healthy adults

目的探究多靶区经颅直流电刺激(tDCS)和单靶区tDCS对健康成年人工作记忆-姿势控制双任务表现的影响,并比较两种刺激方案的调控效果。方法2020年11月至2021年2月,招募上海体育大学19例健康成年人,随机接受多靶区tDCS、单靶区tDCS和假刺激,任意两种刺激之间至少间隔1周。其中,多靶区tDCS的目标靶区为左侧背外侧前额叶(LDLPFC)和双侧初级运动皮质(M1);单靶区tDCS仅刺激L-DLPFC。在每种刺激前后,所有受试者进行单任务和双任务条件下的步行和站立平衡测试,双任务中的第二任务为N-back任务。刺激前后观察双任务姿势控制表现、双任务消耗(DTC)和工作记忆表现。结果刺激后,3种刺激间双任务步行的步幅变异性(F=3.792,P=0.029)、步幅变异性_DTC(F=3.412,P=0.040)以及双任务站立平衡的压心摆动速度(Vcop)(F=3.815,P=0.029)有显著性差异。与假刺激相比,多靶区tDCS后,步幅变异性(P=0.047)和Vcop(P=0.015)降低,步幅变异性_DTC有降低趋势(P=0.073);单靶区tDCS后,步幅变异性(P=0.011)、步幅变异性_DTC(P=0.014)和Vcop(P=0.025)均降低。与单靶区tDCS相比,多靶区tDCS后,压心摆动面积的双任务消耗降低(P=0.035)。3种刺激后受试者工作记忆表现改变无显著性差异(P>0.05)。结论多靶区tDCS和单靶区tDCS均可调控健康成年人的工作记忆-姿势控制双任务表现;且与单靶区tDCS相比,多靶区tDCS在调控站立平衡双任务姿势控制效果上具有一定优势。

Objective To investigate the effect of multi-target transcranial direct current stimulation(tDCS)and single-target tDCS on the performance of working memory-postural control dual-task in healthy adults,and to compare the regulatory effect of the two stimulation protocols.Methods From November,2020 to February,2021,19 healthy adults in Shanghai University of Sport were recruited and randomly accepted multi-target tDCS,single-target tDCS and sham stimulation with at least one week interval between any two stimulation protocols.The target areas of multi-target tDCS included left dorsal lateral prefrontal cortex(L-DLPFC)and bilateral primary motor cortex(M1),and single-tDCS only applied to L-DLPFC.Before and after stimulation,participants completed walking and standing balance tests under single task and dual-task conditions with the second task being a N-back task.The dual-task postural control performance,dual-task cost(DTC)and working memory performance were observed before and after stimulation.Results Significant differences were observed among three stimulation protocols in the changes of stride variability(F=3.792,P=0.029),DTC of stride variability(F=3.412,P=0.040)and velocity of center of pressure(Vcop)(F=3.815,P=0.029).The stride variability(P=0.047)and Vcop(P=0.015)were significantly lower and the decrease in DTC of stride variability tended to be significant(P=0.073)following multi-target tDCS,as compared to sham stimulation.Single-target tDCS significantly decreased the changes of stride variability(P=0.011),DTC of stride variability(P=0.014)and Vcop(P=0.025),as compared to sham stimulation.Compared with single target tDCS,multi-target tDCS reduced the changes of the dual-task cost of the area of center of pressure(P=0.035).Moreover,no significant difference was observed among the three stimulation protocols in the changes of each measure in the working memory test(P>0.05).Conclusion Both multi-target tDCS and single-target tDCS can improve the performance of working memory-postural control dual-task in healthy adults,and compared with single-target tDCS,multi-target tDCS has some advantages in regulating postural control.