有和没有耳石刺激的人体三维前庭眼反射
Human 3-D aVOR with and without otolith stimulation.
作者信息
Bockisch Christopher J, Straumann Dominik, Haslwanter Thomas
机构信息
Department of Neurology, University Hospital Zürich, Frauenklinikstr. 26, 8091 Zürich, Switzerland.
出版信息
Exp Brain Res. 2005 Mar;161(3):358-67. doi: 10.1007/s00221-004-2080-1. Epub 2004 Oct 14.
We describe in detail the frequency response of the human three-dimensional angular vestibulo-ocular response (3-D aVOR) over a frequency range of 0.05-1 Hz. Gain and phase of the human aVOR were determined for passive head rotations in the dark, with the rotation axis either aligned with or perpendicular to the direction of gravity (earth-vertical or earth-horizontal). In the latter case, the oscillations dynamically stimulated both the otolith organs and the semi-circular canals. We conducted experiments in pitch and yaw, and compared the results with previously-published roll data. Regardless of the axis of rotation and the orientation of the subject, the gain in aVOR increased with frequency to about 0.3 Hz, and was approximately constant from 0.3 to 1 Hz. The aVOR gain during pitch and yaw rotations was larger than during roll rotations. Otolith and canal cues combined differently depending upon the axis of rotation: for torsional and pitch rotations, aVOR gain was higher with otolith input; for yaw rotations the aVOR was not affected by otolith stimulation. There was a phase lead in all three dimensions for frequencies below 0.3 Hz when only the canals were stimulated. For roll and pitch rotations this phase lead vanished with dynamic otolith stimulation. In contrast, the horizontal phase showed no improvement with additional otolith input during yaw rotations. The lack of a significant otolith contribution to the yaw aVOR was observed when subjects were supine, prone or lying on their sides. Our results confirm studies with less-natural stimuli (off-vertical axis rotation) that the otoliths contribute a head-rotation signal to the aVOR. However, the magnitude of the contribution depends on the axis of rotation, with the gain in otolith-canal cross-coupling being smallest for yaw axis rotations. This could be because, in humans, typical yaw head movements will stimulate the otoliths to a much lesser extent then typical pitch and roll head movements.
我们详细描述了人类三维角前庭眼反射(3-D aVOR)在0.05 - 1 Hz频率范围内的频率响应。在黑暗中对被动头部旋转测定了人类aVOR的增益和相位,旋转轴与重力方向对齐(地球垂直)或垂直(地球水平)。在后一种情况下,振荡动态刺激了耳石器官和半规管。我们进行了俯仰和偏航实验,并将结果与先前发表的横滚数据进行了比较。无论旋转轴和受试者的方位如何,aVOR的增益随频率增加至约0.3 Hz,并在0.3至1 Hz大致恒定。俯仰和偏航旋转期间的aVOR增益大于横滚旋转期间的增益。耳石和半规管线索根据旋转轴的不同而以不同方式组合:对于扭转和俯仰旋转,有耳石输入时aVOR增益更高;对于偏航旋转,aVOR不受耳石刺激影响。仅刺激半规管时,在0.3 Hz以下的所有三个维度中都存在相位超前。对于横滚和俯仰旋转,这种相位超前在动态耳石刺激下消失。相比之下,在偏航旋转期间,额外的耳石输入并未使水平相位得到改善。当受试者仰卧、俯卧或侧卧时,观察到耳石对偏航aVOR没有显著贡献。我们的结果证实了使用不太自然的刺激(非垂直轴旋转)进行的研究,即耳石为aVOR贡献了头部旋转信号。然而,贡献的大小取决于旋转轴,耳石 - 半规管交叉耦合的增益在偏航轴旋转时最小。这可能是因为在人类中,典型的偏航头部运动对耳石的刺激程度远小于典型的俯仰和横滚头部运动。