文档介绍：轻、中度缺氧应激时声强对脑认知功能的影响
作者:秦云,马瑞山,倪鹤鹦,付兆君,程宏伟
【关键词】低氧
关键词: 低氧;声强;认知
摘要:目的通过分析在4种不同高度和5种不同声强条件下P300 的潜时及波幅,反应时,得出轻、中度缺氧条件下最佳声强值. 方法 14名受试者在地面及1500m,3000m,4500m三个模拟高度(吸低氧混合气体)分别进行5种不同声强值(55,60,70,80,85dB)的听觉oddball测试,记录脑电图(EEG)、反应时(RT)及主观感觉,EEG经平均叠加处理提取出脑事件相关电位(ERP)中的P3 波幅、 潜时和RT为主要指标评定脑认知能力,结合主观评价确定最佳声强值. 结果 P300 潜时及RT,在地面及1500m,5种听觉oddball任务声强为55dB时的P
300 潜时及RT明显长于其它4种声强(P<),,5000m,声强为70,80,85dB时P300 潜时及RT明显短于55dB及60dB的P 300 潜时和RT(P<),而主观评价反映80,85dB声强刺耳,难以忍受. 结论在地面及1500m轻度缺氧情况下最佳声强值为60~70dB;在3000m及5000m中度缺氧条件下,最佳声强值为70~80dB,此时P3 潜时及RT最短;缺氧会减慢脑信息加工过程.
Keywords:anoxia;sound-intensity;cognition
Abstract:AIM To explore the most suitable sound intensity for man in light and moderate hypoxia Fourteen healthy and well trained students were selected as were arranged to perform audio oddball tasks of5different sound intensity(55,60,70,80,85dB)at four attitudes(Ground,1500m,3000m,4500m).486IBM Per-puter was used to produce different sound intensity tones,which were broadcasted to subjects by ear -ter was used to measure sound subjects breathed air or low oxygen mixture to simulate different atti- data and reaction time(RT)were waves of event-related potential(ERP)were latency and RT,as the main indexes to measure the brain cognitive response speed,were analysed by using a2-factor(contrast×attitude)analysis of subject feelings were recorded as another important index of evalua┐ At ground and1500m when sound intensi-ties were60,70,80,85dB,P300 latency and RT were signifi-cantly pared with55dB(P<).But there were no significant differences of P300 latency and RT among and1500m when sound intensities were70,80,85dB,P300 latency and RT were significantly pared with the other two
’s(P<)while significant distinctions among theirs were not to sub-ject feelings