经颅直流电刺激对低氧条件下脑认知功能的影响

Effect of transcranial direct current stimulation on brain cognitive function under hypoxia

目的探究通过经颅直流电刺激技术降低低氧环境对人脑认知功能的影响,为经颅直流电刺激设备的实用化和装备化奠定基础。方法采用常压低氧舱模拟3700 m低氧环境,招募健康志愿者20人进行低氧暴露,对其中10人进行经颅直流电刺激,另外10人进行假刺激,然后分5次测量其反应时、局部脑血氧饱和度、情绪状态量表、闪光融合频率、高原反应量表,对比两组间差异。结果经颅直流电刺激可显著改善被试者的情绪状况,尤其是抑郁、疲劳状态,且能显著增强精力,并能持续6 h以上(在第2~5次测量时P<0.01);此外,该技术可提高人脑警觉度,但维持时间较短,仅在2 h内有效(在第2、3次测量时P<0.01);在4 h内显著提高了脑血氧饱和度,改善人体疲劳状态(在第2、3、4次测量时P<0.01)。结论在低氧环境下经颅直流电刺激可提高人脑警觉度和局部脑血氧饱和度,改善抑郁、疲劳,增强精力。

Objective To investigate the effect of the transcranial direct current stimulation(tDCS)technique on brain cognitive function under a hypoxic environment in order to facilitate the application of tDCS devices.Methods An atmospheric-pressure hypoxic chamber was used to simulate the hypoxic environment of the plateau 3700 meters above sea level.Twenty healthy volunteers were chosen as subjects,who were exposed to a hypoxic environment.Ten of the subjects received tDCS,and the rest underwent sham stimulation.Their response latencies,local cerebral oxygen saturation,the Profile of Mood States,flicker fusion frequency,and altitude sickness scale were measured five times.The differences between them were studied.Results The results showed that tDCS could significantly improve the subjects′emotional state,especially depression and fatigue.Notably,it could improve vigor for more than 6 hours(P<0.01 from the second to fifth measurements).In addition,tDCS could improve the alertness of the brain for a short time(P<0.01 from the second and third measurements).Cerebral oxygen saturation was greatly improved within 4 hours,thus alleviating fatigue(P<0.01 during the second,third and fourth measurements).Conclusion In a hypoxic environment,tDCS can improve alertness,increase local cerebral oxygen saturation,reduce depression and fatigue and boost energy.