The timing of galvanic vestibular stimulation affects responses to platform translation.
The timing of galvanic vestibular stimulation affects responses to platform translation.
复制标题
电前庭刺激的时间会影响对平台平移的反应。
DOI：
10.1016/s0006-8993(98)01356-0
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发表时间：
1999
期刊：
影响因子：
2.9
通讯作者：
Horak,FB
中科院分区：
文献类型：
--
作者：
Hlavacka,F;Shupert,CL;Horak,FB
我们比较了在平台向后平移前刺激S 0、0.5、1.5和2.5时对姿势反应的影响。电流刺激对压力中心最终平衡位置(COP)的影响最大。最大的影响出现在0.5和0-S前期，此时响应于电流刺激和平台平移的动态COP压的变化是一致的。在0.5和0-S前期，最终平衡位置的移位也大于电流刺激和平台平移的移位之和。缔约方会议对平台翻译反应的初始变化率在任何情况下都不会受到重大影响。峰值COP位置的变化可以由单独由原电流和平移反应引起的COP速度变化的局部相互作用来解释，但最终平衡位置的变化只能由全球物体取向的变化来解释。这些发现表明，在姿势反应的动态阶段，前庭脊髓信息的贡献最大，而前庭系统对姿势反应的后期成分，特别是对最终平衡位置的贡献最大。这些结果表明，在体位对电流刺激的反应动态阶段，当两种刺激呈现在1 S以内时，由电流产生的前庭信号和由平台平移产生的感觉刺激之间发生了非线性相互作用。当以更大的时间间隔呈现时，刺激似乎被视为独立的事件，因此不会发生交互作用。
We compared the effects of galvanic vestibular stimulation applied at 0, 0.5, 1.5 and 2.5 s prior to a backward platform translation on postural responses. The effect of the galvanic stimulation was largest on the final equilibrium position of the center of pressure (CoP). The largest effects occurred for the 0.5 and 0-s pre-period, when the dynamic CoP pressure changes in response to both the galvanic stimulus and the platform translation coincided. The shift in the final equilibrium position was also larger than the sum of the shifts for the galvanic stimulus and the platform translation alone for the 0.5 and 0-s pre-periods. The initial rate of change of the CoP response to the platform translation was not significantly affected in any condition. Changes in the peak CoP position could be accounted for by local interaction of CoP velocity changes induced by the galvanic and translation responses alone, but the changes in final equilibrium position could only be accounted for by a change in global body orientation. These findings suggest that the contribution of vestibulospinal information is greatest during the dynamic phase of the postural response, and that the vestibular system contributes most to the later components of the postural response, particularly to the final equilibrium position. These findings suggest that a nonlinear interaction between the vestibular signal induced by the galvanic current and the sensory stimuli produced by the platform translation occurs when the two stimuli are presented within 1 s, during the dynamic phase of the postural response to the galvanic stimulus. When presented at greater separations in time, the stimuli appear to be treated as independent events, such that no interaction occurs.