ELECTRODE DEVELOPMENT

耳蜗电特性和物理形态的研究 电极阵列定义和界定可 用来激活听神经纤维。任何试图预测或 测量这些神经元对给定刺激的反应必须从 一个假定的电极设计。然而，目前所有可用的人工耳蜗 电极基于主要由以下特性决定的设计 常用的材料和制造工艺，而不是 神经元的基本特性和耳蜗学的基础。 此外，到目前为止人工耳蜗术的临床结果表明 许多关于最佳电极设计的原始前提可能 需要修改。该项目的目的是开发和开发 鉴定电极接触材料，定制制作人工耳壳 用于动物实验和台架试验的电极，以及设计新的 电极应该导致假体功能的改善。特定的 任务包括： 1.对现有的临床电极阵列进行表征。 2.探索金属/电解液的界面性质 结，包括新材料的制造和表征，如 作为激活的Ir，它承诺极大地扩展可用的阻抗 此接口的属性。 3.急、慢性动物多触点电极阵列的制作 提供各种精确定位电流的实验 消息来源。 4.建立和检验电极的广义数学模型 界面和几何图形，在坦克中使用场映射技术 实验。 5.设计人类使用的改进型电极阵列，基于 该研究项目和其他项目的研究结果，并建立 这些阵列的原型在动物研究中进行评估。 除了优化电气性能外，该电极还设计成 从这个项目中走出来的人将考虑手术处理等问题 性能和制造经济性，以确保它们可以 很容易被转移到临床听觉假体制造商。

The electrical properties and physical configuration of the cochlear electrode array define and delimit the stimulation strategies that can be employed to activate the auditory nerve fibers. Any attempt to predict or measure the response of these neurons to a given stimulus must start with an assumed electrode design. However, all currently available cochlear electrodes are based on designs determined primarily by the properties of commonly available materials and fabrication processes, rather than on the basis of fundamental properties of neurons and cochlear geometry. Furthermore, clinical results with cochlear prostheses to date suggest that many of the original premises regarding optimal electrode designs may require modification. The purpose of this project is to develop and characterize electrode-contact materials, to custom fabricate intracochlear electrodes for use in animal experiments and bench tests, and to design new electrodes that should lead to improved prosthetic function. Specific tasks include: 1. To characterize existing clinical electrode arrays. 2. To explore the interfacial properties of the metal/electrolyte junction, including fabrication and characterization of new materials such as activated iridium that promise to greatly extend the available impedance properties of this interface. 3. To fabricate multicontact electrode arrays for acute and chronic animal experiments that provide for a variety of accurately positioned current sources. 4. To develop and test generalized mathematical models of electrode interfaces and geometries, using field-mapping techniques in tank experiments. 5. To design improved electrode arrays for human use, based on the findings of this and other projects of the research program, and to build prototypes of these arrays for evaluation in animal studies. In addition to optimizing electrical properties, the electrode designs that emerge from this project will consider issues such as surgical handling properties and economy of manufacture, to assure that they can be transferred readily to manufacturers of clinical auditory prostheses.