CHANNEL INTERACTION IN COCHLEAR IMPLANTS

描述(由申请人提供)：多通道人工耳蜗(CI)旨在通过刺激耳蜗内的不同部位向接受者提供特定频率的信息。然而，耳蜗内多个刺激点的存在增加了这些点之间相互作用的风险。通道相互作用是当CI中的电极刺激重叠的神经群时可能发生的现象。当同时刺激多个电极时，每个电极的电磁场可以在神经刺激之前相加或相减。感知的结果可能是刺激声大得令人不舒服，也可能听不见。当两个电极被快速连续刺激时，神经纤维对第一个电极的反应变得不稳定，因此不能对第二个电极做出反应。结果，语音信号中的一些信息可能没有被听觉外围设备充分编码，这可能会对CI的语音感知性能产生负面影响。以前的研究表明，通道相互作用可以从心理和生理两方面进行测量，但对这两种测量之间的关联程度知之甚少。通道相互作用的心理物理测量对于为单个CI接受者创建最佳语音处理器程序做出决策可能是有用的。不幸的是，制定详细的心理物理措施在临床上是不可行的，因为这是耗时的，对于儿童CI接受者来说通常不可能。然而，使用生理学技术可以相对快速地进行通道相互作用的外围测量。此应用程序的总体目标是确定通道交互的生理测量与通道交互的心理物理测量之间的关系，以及这些测量中的任何一个是否可以帮助临床医生为单个CI接受者选择最佳的语音处理参数。本实验的目的是：(1)研究非同步刺激下通道交互作用的生理和心理物理测量之间的关系；(2)研究同时刺激下的通道交互作用的生理和心理物理测量之间的关系；(3)使用同时和非同时刺激模式下的语音处理策略来研究通道交互作用和言语知觉成绩之间的关系。

DESCRIPTION (provided by applicant): Multi-channel cochlear implants (CIs) are designed to provide frequency-specific information to the recipient by stimulating different sites within the cochlea. However, the presence of multiple stimulation sites within the cochlea increases the risk of interaction between these sites. Channel interaction is a phenomenon that can occur when electrodes in a CI stimulate overlapping neural populations. When multiple electrodes are stimulated simultaneously, current fields from each electrode can sum or subtract prior to neural stimulation. The perceptual result can be a stimulus that is either uncomfortably loud or inaudible. When 2 electrodes are stimulated in rapid succession, nerve fibers become refractory in response to the first electrode and are thus unable to respond to the second electrode. As a result, some information in the speech signal may not be adequately encoded by the auditory periphery, which might have negative effects on speech perception performance with the CI. Previous research has shown that channel interaction can be measured both psychophysically and physiologically, but little is known about the extent to which these 2 measures are related. Psychophysical measures of channel interaction may be useful for making decisions about creating optimal speech processor programs for individual CI recipients. Unfortunately, making detailed psychophysical measures is not clinically feasible because it is time consuming and generally not possible with pediatric CI recipients. However, peripheral measures of channel interaction can be made relatively quickly with physiologic techniques. The overall goal of this application is to determine how physiologic measures of channel interaction are related to psychophysical measures of channel interaction, and if either of these measures can aid the clinician in choosing optimal speech processing parameters for individual CI recipients. The proposed experiments are designed to: (1) investigate the relation between physiologic and psychophysical measures of channel interaction for non-simultaneous stimulation; (2) investigate the relation between physiologic and psychophysical measures of channel interaction for simultaneous stimulation; and (3) investigate the relation between channel interaction and speech perception performance using speech processing strategies that employ both simultaneous and non-simultaneous stimulation modes.