Complex Pitch Perception in Complex Environments

描述(申请人提供)：本项目的长期目标是 进一步加深我们对听觉系统如何形成音调知觉和 这些感知是如何被用来区分来自不同来源的声音的。 该项目有三个主要目标。第一个目标是结合使用 心理物理实验和定量建模以研究音高如何 是在正常和受损的人类听觉系统中编码的。实验将会 听力正常者和耳蜗性听力障碍者的能力调查 (Hi)收听者倾听或分辨出 复杂，并将其与基音编码的总体精度和独立的 频率选择性的衡量标准。据推测，沥青产生了 由分解的谐波产生的谐波与由 仅有未解决的谐波和频率较差的HI听众 选择性可能通常必须依赖于后者，但不太准确 编码。第二个目标是使用类似的方法来测试音高的极限 在更复杂的情况下的感知。这些实验将测试NH和HI 听众一次听到两个音调的能力，并能听出其中一个音调 出现一种相互竞争的汉语化声音。这些能力可能依赖于 至少存在一些已分解的谐波；如果是这样，HI听众可能经常 不能听到两个音调，也不能在…面前听到一个音调 又一个。第三个目标是分别评估信封和信封的影响 精细结构编码(这两种编码都被认为很重要，但 在音高感知中的不同角色)在我们感知分离的能力中 不同的声源。这种方法应用得更多，并试图 量化在复杂背景中传输语音所需的信息， 例如竞争的说话者或波动的噪音。结果可能会有 对人工耳蜗处理器的设计和对 助听器的信号处理算法。

DESCRIPTION (provided by applicant): The long-term goal of this project is to further our understanding of how the auditory system forms pitch percepts and how those percepts are used to separate sounds coming from different sources. The project has three main aims. The first aim is to use a combination of psychophysical experiments and quantitative modeling to investigate how pitch is coded in the normal and impaired human auditory system. Experiments will investigate the ability of normal-hearing (NH) and cochlearly hearing-impaired (HI) listeners to hear out, or resolve, individual harmonic components within a complex, and relate this to overall accuracy in pitch coding and to independent measures of frequency selectivity. It is hypothesized that the pitch produced by resolved harmonics is qualitatively different from that produced by unresolved harmonics alone and that HI listeners with poorer frequency selectivity may often have to rely on the latter, less accurate, form of pitch coding. The second aim is to use similar methods to test the limits of pitch perception in more complex situations. These experiments will test NH and HI listeners' ability to hear two pitches at once and to hear out one pitch in the presence of a competing hannonic sound. It may be that these abilities rely on the presence of at least some resolved harmonics; if so, HI listeners may often not be in a position to hear two pitches, or to hear out one in the presence of another. The third aim is to evaluate separately the influence of envelope and fine-structure coding (both of which are thought to play important but different roles in pitch perception) in our ability to perceptually separate different acoustic sources. This approach is more applied and attempts to quantify the information necessary to transmit speech in complex backgrounds, such as a competing talker or a fluctuating noise. The results may have significant implications for the design of cochlear-implant processors and for signal-processing algorithms for hearing aids.