VESTIBULAR REFLEX ADAPTATION--PHYSICAL REHABILITATION/SURGICAL INTERVENTIONS

一个迷宫的功能损失的补偿是一个重要的 临床问题，以及感觉运动适应的一个很好的例子， 学习接受急性单侧前庭传入阻滞的患者 (UVD)，作为听神经瘤或梅尼埃病的手术干预 疾病，患有各种前庭，眼，和姿势 紊乱最初，他们有强烈的自发性眼球震颤， 前庭张力突然失衡， 几周后。与这种静态的不平衡相关联的是一种动态的 干扰：前庭的增益（眼睛速度/头部速度）- 眼反射（VOR），在响应头部旋转，是显着的 降低，并且对于朝向损伤侧的旋转更低。这导致 姿势稳定性、定向障碍、头晕和模糊 头部运动时的视觉。VOR的增益逐渐增加， 变得更加对称。然而，VOR增益的测试具有快速，高- 头部旋转的加速度步骤显示出降低的和不对称的增益 甚至在神经切除后的一年内。 我们提出了一系列的研究，旨在提高我们的知识， 对UVD的补偿过程。这些研究将帮助我们更好地 了解正常人的前庭适应，并将帮助我们 制定适当的练习，以最迅速和有效地 UVD后患者的康复。该项目有四个主要目标。 首先，研究正常人对不对称前庭刺激的适应性， 人类第二，要衡量患者适应这些相同的能力， 刺激，并确定在这种情况下的适应能力是否增强 他们补偿UVD的能力。第三，设计视觉前庭 刺激，提供最迅速和完整的增加，在增益 正常人的VOR，作为将这些相同刺激应用于 UVD患者的锻炼。四、促进前庭功能恢复 功能-即使VOR的增益不能增强-由一个 一个快速的眼睛和头部运动到视觉目标的程序。这 任务再现了UVD患者感到困扰的那些情况 在恢复期间;它在临床和实验室的研究可以帮助我们 确定患者采用的那些策略，以增加 VOR不足，因此我们可以专门针对这些战略， 物理治疗项目。

Compensation from the loss of function of one labyrinth is an important clinical problem, and an excellent example of sensorimotor adaptation and learning. Patients who undergo acute unilateral vestibular deafferentation (UVD), as a surgical intervention for acoustic neuroma or Meniere's disease, suffer from a variety of vestibular, oculomotor, and postural disorders. Initially, they have a vigorous spontaneous nystagmus due to the sudden imbalance of vestibular tone, which largely resolves itself after a few weeks. Associated with this static imbalance is a dynamic disturbance: the gain (eye velocity / head velocity) of the vestibular- ocular reflex (VOR), in response to head rotations, is significantly decreased, and is lower for rotations toward the lesioned side. This leads to problems of postural stability, disorientation, dizziness, and blurred vision during head motion. The gain of the VOR gradually increases and becomes more symmetric. However, tests of VOR gain with rapid, high- acceleration steps of head rotation show a decreased and asymmetric gain even up to a year after nerve section. We propose a series of studies designed to enhance our knowledge of the process of compensation to UVD. These studies will help us better to understand vestibular adaptation in normals, and will aid us in the development of appropriate exercises for the most rapid and effective rehabilitation of patients after UVD. This project has four major aims. First, to study adaptation to asymmetric vestibular stimuli in normal humans. Second, to measure the ability of patients to adapt to these same stimuli, and determine if adaptive capability in this situation enhances their ability to compensate for UVD. Third, to design visual-vestibular stimuli that provide the most rapid and complete increases in the gain of the VOR in normals, as a preliminary to applying these same stimuli to exercises for UVD patients. Fourth, to promote recovery of vestibular function -- even if the gain of the VOR can not be enhanced -- by a program of rapid combined eye and head movements to visual targets. This task reproduces those circumstances that UVD patients find troubling during recovery; its study in the clinic and laboratory can help us to determine those strategies that patients employ in order to augment an insufficient VOR, so that we can specifically target these strategies in programs of physical therapy.