Optimized Conditioned Processing for Cochlear Implants

高水平的言语知觉在安静的是目前可用于一个显着的百分比的现代 cdcampaign植入受体。然而，在噪声背景中，特别是如果噪声是竞争语音， 言语感知能力严重受损。噪声环境下改善语音感知的一种可能方法 改善电刺激听觉神经放电模式中言语的时间表征 神经纤维这种方法也有望改善双侧种植体的性能 接受者需要进行脑干分析的任务。详细的生物物理模型和 动物研究已经证明，可以通过 使用“条件刺激”-未调制的高速率脉冲序列， 竞争信号的神经元。使用这个程序已经导致了显着增加的言语感知 在某些受试者中，安静和/或噪音，但在其他受试者中则不然。拟议工作的目标是优化 呈现语音信号和调节器，以便在安静时最大化语音感知 以及改善基于时间的偏侧化的感知 和双耳暴露。因为时间音高机制要求精确的 位置信息，如果他们是有用的，和音高被认为是关键的言语歧视，在竞争中 滤波器到电极的映射将在有条件的语音处理器中被操纵，以最大化 在稳态噪声、“多路重合噪声”、时间调制噪声中， 以及语音形状噪声中的提示语句。结果将允许优化条件 单侧和双侧人工耳蜗植入者的处理器。在那些双侧植入接受者中， 在生理范围内对电刺激具有耳间时间感知，这项工作具有潜力， 从临床语音处理器中提供显著的额外双耳益处 可通过耳间振幅差获得。在单方面被剥夺者中，这项工作已经证明， 在有限数量的受试者中获得实质性益处;我们的目标是将这些益处提供给更广泛的受试者。 植入物接受者的人群。

High levels of speech perception in quiet are currently available to a significant percentage of modern cdchlear implant recipients. In a noisy background, however, particularly if that noise is competing speech, speech perception is dramatically impaired. One possible method for improving speech perception in noise is to improve the temporal representation of speech in discharge patterns of electrically stimulated auditory nerve fibers. This method would also be expected to improve the performance of bilateral implant recipients on tasks requiring brainstem analysis of interaural timing. Detailed biophysical models and animal studies have demonstrated that improved temporal representation can be accomplished through the use of "conditioning stimuli" - trains of unmodulated high-rate pulses that desynchronize activity of auditory neurons to competing signals. Use of this procedure has led to dramatically increased speech perception in quiet and/or noise in some subjects, but not in others. The goal of the proposed work is to optimize the presentation of both the speech signal and the conditioner so as to maximize speech perception in quiet and noise for unilateral implant recipients, as well as improve perception of temporally-based lateralization and binaural unmasking in bilateral implantees. Because temporal pitch mechanisms demand accurate place information if they are to be useful, and pitch is thought critical for speech discrimination in competing speech, filter-to-electrode mappings will be manipulated in conditioned speech processors to maximize performance on a test of spondees in steady-state noise, "babble noise", temporally modulated noise, as well as on HINT sentences in speech-shaped noise. The results will allow optimization of conditioned processors for unilateral and bilateral cochlear implant recipients. In those bilateral implant recipients who have interaural timing perception for electrical stimuli in the physiologic range, this work has the potential to provide significant additional binaural benefits from a clinical speech processor beyond those currently available via interaural amplitude differences. In unilateral implantees, this work has already demonstrated substantial benefit in a limited number of subjects; it is our goal to deliver these benefits to the broader population of implant recipients.