不同前庭刺激下人体心率变异性的变化特征

The characteristics of heart rate variability (HRV) under various vestibular stimuli

目的 观察不同前庭刺激下人体心率变异性 (HRV)的变化特征。 方法 33名健康受试者在 15 0s、10°/s匀速旋转后 ,分别进行 0 6°/s2 、0 8°/s2 、1 0°/s2 和 1 2°/s2 梯形旋转刺激 ,旋转的同时完成听觉认知任务并记录心电信号。 结果 匀速旋转和角加速度作用时HRV的变化特征明显不同。相对于试验前对照 ,匀速旋转时心率和HRV没有发生变化 ,但反应时显著缩短 ,正确率升高 ;而角加速度作用时 ,相对于试验前对照和匀速旋转 ,出现心率和HRV极低频功率显著降低 ;相对于试验前对照 ,反应时和正确率没有发生变化 ,但相对于匀速旋转出现反应时延长 ,1 2°/s2 时正确率下降。 结论 匀速旋转对HRV分析所表示的心血管活动没有影响 ,但对中枢可能有激活作用 ;角加速度作用时 ,HRV极低频功率显著降低 ,表明角加速度作用时主要是中枢对心血管的调节作用发生了显著改变。

Objective To observe the HRV characteristics under various vestibular stimuli and the relationship between the HRV changes and auditory cognitive activities. Methods The ECG signals were recorded in 33 subjects when vestibular stimuli of 0.6°、0.8°、1.0°、1.2°/s 2 trapezoid angular acceleration were given with preliminary 10°/s rotation in Barany chair for 150 s. In the meantime subjects were asked to perform auditory selective task using reaction time(RT) and accuracy as indexes. Results As compared with that before experiment,HR and HRV during constant angular rotation were unchanged,while RT of selective task was shortened and accuracy increased significantly. On the contrary HR and VLF component of HRV during constant angular acceleration were significantly decreased,while the changes of RT and accuracy were non-significant. Conclusions Vestibular stimulus of constant angular rotation does not affect cardiovascular activities in terms of HRV,but can activate CNS activities. The decrease of HR and VLF component of HRV under stimuli of angular acceleration seems to be mainly due to the change of regulation effect of CNS on cardiovascular activities.