目的:探究额顶叶θ-经颅交流电刺激(theta-transcranial alternating current stimulation,θ-tACS)对健康成年人不同姿势条件下(坐位和站立位)工作记忆表现的影响.方法:本研究为随机、交叉、双盲设计.选取16名健康成年人,以随机顺序进行tACS真刺激和假刺激,两次刺激之间至少间隔72h.tACS方案使用7个电极放置于左侧额顶叶振荡关键脑区,频率选择为6Hz,持续21min.假刺激方案使用与tACS真刺激方案相同的刺激靶区、频率,但只进行1min的刺激(刺激开始和结束各30s).在刺激前和刺激后即刻评估坐位及站立位n-back工作记忆表现,包括正确率、反应时和逆效率得分.采用Wilcoxon秩和检验观察刺激方式对工作记忆影响的组间及组内差异.结果:15名受试者完成试验,两种刺激条件均未出现明显副作用和不良反应.额顶叶θ-tACS后,坐位工作记忆的反应时、逆效率得分与站立位的反应时改善显著(P＜0.05),站立位逆效率得分具有改善趋势(P=0.057);与刺激前相比,假刺激后坐位及站位工作记忆均无显著性差异(均P＞0.05).结论:额顶叶θ-tACS可以改善坐位和站立位不同姿势下的工作记忆表现,有助于健康成年人应对现实生活中的多任务认知活动,具有重要的实践应用价值.
Effects of frontoparietal transcranial alternating current stimulation on working memory in different pos-tures
Objective:To investigate the effect of theta-transcranial alternating current stimulation(θ-tACS)over the frontal-parietal cortex on working memory(WM)performance under different postural conditions(sitting and stand-ing)in healthy adults.Method:The study was a randomized,crossover,double-blind design.Sixteen healthy adults received tACS or sham stimulation in random order,with at least 72 hours interval between two sessions.Seven electrodes were placed in the left frontoparietal critical brain region with 6Hz for 21 mins.The sham stimulation used the same stimulation time and frequency as tACS group,but only 1 minute of stimulation(30s at the beginning and 30s at the end of the stimulation).WM performance was assessed before and immediately after stimulation,in-cluding accuracy,reaction time and inverse efficiency scores.Wilcoxon rank sum tests were used to observe between-and within-group differences on WM performance.Result:Fifteen participants completed the experiment and there were no significant differences in side effects be-tween two groups.There was a significant improvement in reaction time and inverse efficiency scores for sit-ting WM as well as reaction time for standing WM after the frontoparietal θ-tACS(P＜0.05).There was a trend towards improvement in inverse efficiency scores for standing WM(P=0.057),while there was no signif-icant difference in accuracy,reaction time and inverse efficiency scores of WM during the sitting and standing conditions in the sham stimulation(all P＞0.05).Conclusion:Frontoparietal θ-tACS can improve WM performance in both sitting and standing postures.This helps healthy adults cope with real-life multitasking cognitive activities and has important practical application value.
working memorytranscranial alternating current stimulationhealthy adults
NETL
NSTL
万方数据
