Development of semicircular canal prostheses for studies of vestibular plasticity

超过9000万美国人（>40%）将因头晕或其他平衡障碍而寻求医疗护理 有时在他们的生活中。美国国立卫生研究院的一个工作委员会报告说，至少有200万美国人经历了 由于头晕或其他平衡障碍造成的慢性损害，导致医疗费用超过1美元 每年10亿。这些患者中的一些人可以从前庭假体中受益， 人工耳蜗用于治疗深度感音神经性听力损失。我们的工作发展前庭 由于我们对前庭可塑性的理解存在缺陷， 对由我们的假体提供的慢性前庭刺激的反应受到设备限制的限制，或者如果 实验观察到的塑性极限本质上是基本的和生理的。我们的理解 由于传统技术（例如，化学或外科手术 前庭神经切除术、神经管堵塞），这些方法可用于长期操纵前庭信号， 可控的和/或可逆的。为了解决这些临床和科学局限性，我们建议开发一种 新的假体装置，可以长期使用，以刺激半规管。我们的建议书是这样写的 在直接响应计划公告PA-04-006（“神经技术研究开发和 增强”）。我们提议开发的新设备将使科学调查能够实现， 可能使用现有的技术，同时也从根本上推进前庭假体。具体地说， 我们建议设计、开发和测试一种新的动态的、慢性的、可控的、流体动力的管道， 刺激器这个装置结合了微控制器电路，就像为我们的前庭假体开发的那样， 用慢性机械致动器推动单个半规管中的内淋巴，反过来， 使吸盘偏转。该装置将提供对内淋巴运动的慢性动态控制，这是一种有效的方法。 正常旋转转换的基本部分，以单独的管道，这样的增益，动力学，和/或 在非人灵长类动物中，植入管的表观解剖平面可以可控地改变。的 装置甚至能够在没有旋转的情况下提供耳道刺激。我们建议用这个 设备进行四个假设驱动的科学调查。具体而言，我们建议：1）测量 高频（>50 Hz）VOR反应，2）测量由 前庭信号与提供视觉反馈变化的标准方法相反， 指导VOR运动学习，3）测量诱发电位以评估疗效和稳定性， 提供外周前庭刺激; 4）观察半规管刺激对倾斜的影响 感知，直接测试的假设，运河信号影响倾斜的看法。

Over 90 million Americans (>40%) will seek medical attention for dizziness or some other balance disorder sometime in their life. An NIH working committee has reported that at least 2 million Americans experience chronic impairment due to dizziness or other balance disorders, causing medical expenses in excess of $1 billion per year. Some of these patients could benefit from a vestibular prosthesis that would be similar to the cochlear implant used to treat profound sensorineural hearing loss. Our work developing vestibular prosthetics is limited by shortcomings in our understanding of vestibular plasticity, since we cannot assess if responses to chronic vestibular stimulation provided by our prosthesis are restricted by device limitations or if the plastic limitations observed experimentally are fundamental and physiologic in nature. Our understanding of vestibular plasticity is limited because the traditional techniques (e.g., chemical or surgical labyrinthectomy, canal plugging) that are available to chronically manipulate the vestibular signals are not controllable and/or reversible. To address these clinical and scientific limitations, we propose to develop a new prosthetic device that can be used chronically to stimulate a semicircular canal. Our proposal is written in direct response to program announcement PA-04-006 ("Neurotechnology Research Development & Enhancement"). The new device that we propose to develop will enable scientific investigations that are not possible using existing techniques while also fundamentally advancing vestibular prostheses. Specifically, we propose to design, develop, and test a new dynamic, chronic, controllable, fluid-dynamic, canal stimulator. This device combines microcontroller circuitry, like that developed for our vestibular prosthesis, with a chronic mechanical actuator that pushes endolymph in an individual semicircular canal, which, in turn, deflects the cupula. This device will provide chronic dynamic control of endolymph movement, which is an essential part of normal rotation transduction, to an individual canal such that the gain, dynamics, and/or the apparent anatomic plane of the implanted canal can be controllably altered in non-human primates. The device will even be capable of providing canal stimulation in the absence of rotation. We propose to use this device to perform four hypothesis-driven scientific investigations. Specifically, we propose: 1) to measure high-frequency (>50 Hz) VOR responses, 2) to measure VOR adaptation evoked by changes in the vestibular signals as opposed to the standard approach of providing changes in the visual feedback that guides VOR motor learning, 3) to measure evoked potentials to evaluate efficacy and stability of the peripheral vestibular stimulation being provided, 4) to investigate the influence of canal stimulation on tilt perception, directly testing the hypothesis that canal signals influence tilt perception.