CI Neural Mechanisms

项目摘要/摘要 人工耳蜗术被广泛认为是最能直接刺激听神经的植入物。 成功的神经假体装置。然而，CI患者不像人一样能听懂语言。 在听力正常的情况下，仍有尚未满足的临床需求，以改善已建立的CI用户的表现。 通过改变每个电极上的刺激参数来调整每个听者的CI(“编程”)； 然而，自从配置项首次由 美国食品和药物管理局于1984年提出。研究表明，1)AN纤维的估计密度会影响语音识别 CI用户的结果，2)CI用户中每个电极位置的密度可以被估计，以及3)语音 当刺激具有较高AN密度的电极位置时，一些CI用户的识别能力有所提高。而这些 研究表明，语音识别似乎至少在某种程度上依赖于语音识别的能力 准确地编码信号，在听觉皮质水平上对信息进行编码对 充分的语音理解能力。本研究将定义密度在精确编码中的作用 “定时”(时间)信息并量化具有较高AN密度的刺激电极的程度 在听觉皮质水平上影响时间信息的编码。我们假设用户会 使用刺激具有更高An的电极的CI计划时，显示改善的语音理解能力 密度，但这些改进将与更精确地编码 听觉皮质。

PROJECT SUMMARY/ABSTRACT Cochlear implants (CIs), which directly stimulate the auditory nerve (AN), are widely considered to be the most successful neuroprosthetic device. However, patients with CIs do not understand speech as well as people with normal hearing, and there remains an unmet clinical need to improve performance in established CI users. CIs are adjusted for each listener by varying the stimulus parameters on each electrode (“programming”); however, programming techniques have largely remained unchanged since CIs were first approved by the FDA in 1984. Studies have shown that 1) the estimated density of AN fibers affects speech recognition outcomes in CI users, 2) AN density can be estimated at each electrode site in CI users, and 3) speech recognition improves for some CI users when stimulating electrode sites with higher AN density. While these studies show that speech recognition seems to be at least somewhat dependent on the ability of AN to precisely code the signal, encoding of information at the level of the auditory cortex is also important for adequate speech understanding. The present studies will define the role of AN density in the precise coding of “timing” (temporal) information and quantify the extent to which stimulating electrodes with higher AN density affects encoding of temporal information at the level of the auditory cortex. We hypothesize that users will show improved speech understanding when using a CI program that stimulates electrodes with higher AN density, but these improvements will be associated with more precise encoding of temporal cues within the auditory cortex.