摇头刺激对健康青年人前庭脊髓反射功能的影响

Postural stability after head-shaking in the healthy young individuals

目的:定量分析健康青年人摇头后静态姿势稳定性的变化,初步探讨摇头刺激对人体前庭脊髓反射功能的影响。方法:28例健康青年人进行静止头位和摇头后的静态姿势描记,计有4种测试条件:①头部直立,睁眼(T1);②头部直立,闭眼(T2);③摇头后,睁眼(T3);④摇头后,睁眼(T4),每种测试条件均静态直立30s。摇头的方法为:头部向下倾30°,以左右方向30°做水平面摇头20 s,频率2 Hz。摇头结束后,头置于正中水平位,分别记录睁眼和闭眼的姿势稳定性。静态姿势描记仪记录不同测试条件下身体直立时足底压力中心晃动的平均速度(sway velocity,SV)为研究参数。结果:本组受试者均未在摇头后发生倾倒。①分析摇头刺激对姿势平衡的影响:睁眼时摇头前后,即T3与T1比较SV增加了(4.60±6.36)%;而闭眼时摇头前后,即T4与T2比较SV增加了(8.86±8.27)%,这两增幅间差异有统计学意义(t=2.759,P<0.01)。②分析视觉在静态和动态头位下维持平衡中的作用:静止头位下,T2与T1比较SV增加了(9.83±5.10)%;摇头后,即T4与T3比较SV增加了(14.05±6.89)%,增幅间差异有统计学意义(t=2.772,P<0.01)。结论:摇头刺激可干扰前庭觉信息传入,影响健康人体的前庭脊髓反射功能,导致静态姿势平衡功能降低,且当视觉同时受到干扰时对姿势平衡的影响更为显著。人体为维持摇头后直立平衡,存在对感觉信息的重新整合机制。

Objective：To investigate the postural stability after head-shaking in the normal young individuals. Method：Twenty-eight normal young individuals were taken the static posturography under 4 standing conditions including （T1） head center and eye open（EO）, （T2） head center and eye closed, （T3） after head-shaking and EO, （T4） after head shaking and EC. The sway velocity （SV） of center of pressure under feet in each testing condition was recorded as parameter and each test protocol was 30 s. Result： All examinee did not fall in each testing condition. （1）The SV increased （4.60±6.36）M after head-shaking in the EO condition, while the （8.86±8.27）% was demonstrated in the EC condition. There was significant difference between these two degrees of increase （t = 2. 759,P〈0.01）. （2）In static head orientation, the SV of EC （T2） increased （9.83±5.10）% compared with the SV of EO condition （T1）. However, the SV of EC （T4） increased （14.05±6.89） % compared with the SV of EO condition （T3） after head-shaking. And there was significant difference between these two degrees of increase （t= 2. 772, P〈0. 01）. Conclusion：The stimuli of head-shaking that interrupted input from vestibular end organ can affect the function of vestibulospinal reflex in healthy young individual, especially when the visual input was interrupted simultaneously. In order to keeping balance after head-shaking, there was a complex mechanism sensory reorganization even in the normal young subject.