Kamura E, Yagi T
Department of Otolaryngology, Nippon Medical School, Tokyo.
Nihon Jibiinkoka Gakkai Kaiho. 1999 Jan;102(1):42-9. doi: 10.3950/jibiinkoka.102.42.
Off-vertical axis rotation (OVAR) is a method to stimulate the otolith organ. In order to elucidate the function of the otolith organ, we analyzed three-dimensional eye movements by video-oculographic technique during OVAR in 30 normal subjects. The eye movements induced by OVAR stimulation have two components: a constant horizontal deviation in the direction opposite to the rotation known as the bias component, and sinusoidal amplitude changes of eye movements known as the modulation component. Modulation components were detected in the horizontal, vertical, and torsional eye movements, but the bias components were only detected in the horizontal eye movements. The modulation components may compensate for changes in head orientation with respect to gravity. Since the bias component is caused by the velocity storage mechanism, the lack of bias components in vertical and torsional eye movements may suggest its specific relation to only horizontal eye movements. Our results also demonstrated that torsional and horizontal eye movements may originate from the utricle, whereas vertical eye movement may originate from the saccule. However, a lag phase between torsional and horizontal eye movements suggests that the most effective direction for stimulation of these two eye movements may be different.
离垂直轴旋转（OVAR）是一种刺激耳石器官的方法。为了阐明耳石器官的功能，我们通过视频眼动技术分析了30名正常受试者在OVAR过程中的三维眼动。OVAR刺激引起的眼动有两个组成部分：在与旋转方向相反的方向上有一个恒定的水平偏差，称为偏差分量；眼动的正弦幅度变化，称为调制分量。在水平、垂直和扭转眼动中均检测到调制分量，但仅在水平眼动中检测到偏差分量。调制分量可能补偿头部相对于重力的方向变化。由于偏差分量是由速度存储机制引起的，垂直和扭转眼动中缺乏偏差分量可能表明其仅与水平眼动有特定关系。我们的结果还表明，扭转和水平眼动可能起源于椭圆囊，而垂直眼动可能起源于球囊。然而，扭转和水平眼动之间的滞后阶段表明，刺激这两种眼动的最有效方向可能不同。
