Perceptual implications of cochlear implant electrode-neuron interfaces

项目摘要/摘要 人工耳蜗术是一种非常成功的神经假体，可以严重增强或恢复听力。 听力受损的成年人和儿童。来自环境的声音被转化为电脉冲，并 通过一组电极传送到听神经。人工耳蜗术提供了重要的频谱和 提供给收听者的时间信息。然而，语音感知性能在不同的人之间有很大的差异 人工耳蜗收听者，特别是在嘈杂环境和复杂刺激下。这种可变性是存在的 即使是在发育早期(2岁)接受人工耳蜗植入的儿童也是如此。 最近的证据表明，儿童拥有更高密度的健康听觉神经元，这是 通过植入物刺激的目标。听觉发育可塑性也有一个关键期。 这些因素的相互作用与人工耳蜗术中的慢性电刺激并不是很好。 理解，特别是对早期植入的儿童。尽管成年人和成年人之间存在这些已知的差异 对于听觉系统不成熟的儿童，人工耳蜗术的研究主要集中在成人。在成年人中，最多的 用于优化编程策略的有前景的方法包括聚焦每一个所发射的电场 电极刺激更受限制的神经元群体，并使不那么有效的电极失活。非常 很少有人尝试优化专门针对儿童的方案编制战略，最近 有证据表明，与成年人相比，儿童从集中刺激中受益更多。此外，当新的 实施编程策略时，评估其所需时间的数据有限 有效性。 提出了三个目标：1)确定儿童光谱分辨率的潜在机制 通过比较不同年龄段的外周生理和行为调谐 寿命；2)量化儿童和成人在使用时言语感知的短期变化(超过几个小时) 带有和不带有聚焦刺激的选择性通道停用的优化编程策略； 以及3)量化儿童和成人言语感知的长期变化(在几周内) 优化策略，如目标2所示。 拟议的研究结果有望促进我们对植入的 听觉系统的发展，应该如何对人工耳蜗进行编程，以最好地提供频谱挑战 信号，以及适应方案编制战略变化的时间进程。这些发现可能 指导临床决策，何时进行规划调整，调整哪些类型 调整后，患者需要多长时间才能达到最佳表现。这些研究的结果 研究最终可能会改善植入人工耳蜗术的儿童和成人的功能结果。

Project Summary/Abstract Cochlear implants are highly successful neural prostheses that enhance or restore audition to severely hearing-impaired adults and children. Sound from the environment is converted into electrical pulses and conveyed to the auditory nerve by an array of electrodes. The cochlear implant provides important spectral and temporal information to the listener. However, speech perception performance varies considerably among cochlear implant listeners, particularly in noisy environments and for complex stimuli. This variability exists even for children who receive their cochlear implants early in development (<2 years old). Recent evidence suggests that children have a higher density of healthy auditory neurons, which are the target of stimulation through an implant. There is also a critical period for auditory developmental plasticity. The interaction of these factors and the chronic electrical stimulation of a cochlear implant are not well understood, especially for early-implanted children. Despite these known differences between adults and the immature auditory systems of children, cochlear implant research has focused on adults. In adults, the most promising methods for optimizing programming strategies include focusing the electrical field emitted by each electrode to stimulate a more restricted population of neurons and deactivating less effective electrodes. Very few attempts have been made to optimize programming strategies specifically for children, and recent evidence suggests children would benefit more than adults from focused stimulation. Moreover, when new programming strategies are implemented, there is limited data about the timecourse needed to assess their effectiveness. Three aims are proposed: 1) Determine the underlying mechanisms for spectral resolution in children and adults with cochlear implants by comparing peripheral physiological and behavioral tuning across the lifespan; 2) Quantify short-term changes (over hours) in speech perception in children and adults when using optimized programming strategies with selective channel deactivation with and without focused stimulation; and 3) Quantify long-term changes (over weeks) in speech perception in children and adults using the same optimized strategies as in Aim 2. The results of the proposed studies are expected to advance our understanding of how the implanted auditory system develops, how cochlear implants should be programmed to best deliver spectrally challenging signals, and the timecourse of acclimatization to changes in programming strategies. These findings could guide clinical decision making about when to make programming adjustments, what types of adjustments to make, and how long patients need to reach peak performance following adjustments. The results from these studies could ultimately lead to improved functional outcomes for children and adults with cochlear implants.