The effects of cochlear hearing loss on the perception of pitch and temporal fine structure

听力障碍是一个主要的健康问题，影响大约六分之一的人。残疾是与朋友和家人沟通的障碍，使日常人际接触变得困难和尴尬，并损害了音乐的享受。随着人口老龄化的加剧，这个问题可能会变得更糟。然而，目前的助听器在其有效性方面受到限制。特别是，它们在我们日常生活中经常遇到的嘈杂环境中对理解语音没有太大帮助。音高是主要的听觉感觉之一。它是音乐旋律和一些重要的语音信息的基础，如韵律（话语的重音模式）。它还可以帮助我们区分出一起出现的声音，比如在嘈杂的背景中说话。音高是由大脑中的神经细胞代表的，部分是由同步发射的电脉冲代表的。最近有人提出，这？时间密码可能会干扰听力损失的人。这可能不仅对音高感知，而且对从背景噪声（例如，在嘈杂的聚会中的单个扬声器）中听出感兴趣的声音的能力具有不利影响。由于后一种缺陷是听障听众遇到的主要问题，因此我们了解这些限制是很重要的。此外，听力受损的人经常会经历音调的异常变化，这可能会极大地影响音乐的享受。这些变化也可能与时间赤字有关。我们的研究将调查这些缺陷的原因和性质。我们将使用行为任务，其中听力正常和受损的人类参与者将通过耳机对呈现给他们的声音做出决定。这些任务将测量感知限制。我们还将使用一种技术，该技术涉及记录参与者听声音时大脑中神经细胞的电活动，使用连接到头部的电极。这项技术将测量大脑中音高信息的编码，并使我们能够调查受损听众所经历的缺陷的生理基础。希望这些结果将为确定个体时间编码障碍的性质提供新的诊断技术，并使我们能够设计出更有效的助听器来弥补这些缺陷。

Hearing impairment is a major health issue, affecting roughly 1 in 6 people. The disability is a barrier to communication with friends and family, makes everyday human contact difficult and embarrassing, and impairs enjoyment of music. With an increasingly aged population, the problem is likely to get worse. However, current hearing aids are limited in their effectiveness. In particular, they do not provide much help in understanding speech in the noisy environments we often encounter in our everyday lives. Pitch is one of the primary auditory sensations. It underlies musical melody and some important speech information such as prosody (the stress pattern of an utterance). It is also important in helping us to separate out sounds that occur together, such as speech in a noisy background. Pitch is represented by nerve cells in the brain in part by the synchronized firing of electrical impulses. Recently it has been suggested that this ?temporal code? may be disrupted in people with hearing loss. This may have an adverse effect, not only on pitch perception, but also on the ability to hear out the sound of interest from background noise (for example, a single speaker at a noisy party). Since this latter deficit is the main problem experienced by hearing-impaired listeners, it is important that we understand these limitations. In addition, hearing-impaired people often experience abnormal shifts in pitch that may greatly impair the enjoyment of music. These shifts may also be related to the temporal deficit. Our research will investigate the causes and nature of these deficits. We will use behavioural tasks, in which human participants with normal and impaired hearing will make decisions regarding sounds presented to them over headphones. These tasks will measure perceptual limitations. We will also use a technique that involves recording the electrical activity of nerve cells in the brain as the participants listen to sounds, using electrodes attached to the head. This technique will measure the coding of pitch information in the brain, and will allow us to investigate the physiological basis of the deficits experienced by impaired listeners. It is hoped that the results will suggest new diagnostic techniques for determining the nature of the temporal coding impairment on an individual basis, and allow us to design more effective hearing aids that compensate for these deficits.