AUDITORY IMPLANT PERCEPTION IN ONGOING BACKGROUNDS

多通道人工耳蜗植入已经取得了惊人的成功， 把语言交流的世界带给深度失聪的人。 然而，即使是最好的植入用户也会经历言语减少 在存在背景噪声的情况下的可懂度。这可能会使一个 普通的社交活动，如在餐馆用餐， 艰难的奋进 我们的假设是噪声影响植入 监听方式有两种：第一，降低动态范围， 响度增长功能，第二，它改变了听众; 对刺激的时变方面的敏感性（如调制） 相对而言，人们对植入式听力的心理物理学知之甚少 在嘈杂的背景下。 本研究的总体长期目标 就是要深入了解这些背景的影响， 在多电极中感知简单和复杂声音 植入患者。 电听觉的两个基本方面是 本提案涉及： 1.有限的动态范围：植入式监听器的动态范围非常有限 范围从阈值到不舒适的响度水平（响度）。 我们预计 噪声背景将提高阈值并降低阈值， 招聘（Recruitment）。 然而，压缩动力学的影响 响度函数的形状的范围是未知的。 实验1 将测量两个音调和调幅信号的响度增长， 存在宽带、带通和低通滤波噪声。 2.对振幅调制的灵敏度：作为光谱的程度， 植入收听者可获得的细节特别有限， 对于正常听力来说，对时间波动的敏感性可能会起作用， 在从植入物获得的益处中发挥重要作用。 实验2 将调查植入式听众对振幅的敏感性 在存在具有不同频谱时间的噪声的情况下的调制 特色 实验将在Nucleus和Clarion用户中进行 系统. 对于每个实验条件，不同程度的 将使用信号和噪声之间的电极分离， 解决电极或通道相互作用的问题， 多电极听力的重要因素。 预计本研究将a）在开发中发挥作用 未来几代听觉植入语音处理器和B） 深入了解听觉感知的基本机制 噪音。

Multi-channel cochlear implants have achieved phenomenal success in bringing the world of speech communication to the profoundly deaf. However, even the best implant users experience reduced speech intelligibility in the presence of background noise. This may turn an ordinary social activity such as dining at a restaurant, into a difficult endeavor. Our Hypothesis is that noise influences implant listening in two ways: first, it reduces the dynamic range and changes the loudness growth function and second, it changes the listeners; sensitivity to time-varying aspects of stimuli (such as modulation) Relatively little is known about the psychophysics of implant listening in noisy backgrounds. The overall long-term objective of this research is to achieve in-depth understanding of the effects of such backgrounds on the perception of simple and complex sounds in multi-electrode implant patients. Two fundamental aspects of electrical hearing are addressed in this proposal: 1. Limited dynamic range: Implant listeners have a very limited dynamic range from threshold to uncomfortable loudness level (ULL). We expect that a noise background will raise the threshold and lower the ULL of the tone ("recruitment"). However, the effect of the compressed dynamic range on the shape of the loudness function is unknown. Experiment 1 will measure loudness growth of both tones and AM signals in the presence of wideband, bandpass and lowpass filtered noise. 2.Sensitivity to amplitude modulations: As the degree of spectral detail available to implant listeners is particularly limited compared to normal hearing, sensitivity to temporal fluctuations may play an important role in the benefit derived from the implant. Experiment 2 will investigate the sensitivity of implant listeners to amplitude modulation in the presence of noise with different spectro-temporal characteristics. Experiments will be performed in users of both Nucleus and Clarion systems. For each experimental condition, different degrees of electrode separation between signal and noise will be used in order to address the issue of electrode- or channel- interaction, a third important factor in multi-electrode hearing. It is expected that this research will a) play a role in the development of future generations of auditory implant speech processors and b) provide insight into the fundamental mechanisms of auditory perception in noise.