Cortical representations of harmonic and virtual pitch in humans

项目总结 音高和和声在人们对语言和音乐的感知中起着决定性的作用，并且对 听觉场景中声音的知觉组织。听力损失的听众，以及 尤其是那些植入了人工耳蜗的人，他们在音调感知能力方面存在显著缺陷，因为 当前的声音处理策略不能提供稳健的音调提示。这种音调线索的缺乏是 他们不能在噪声中感知语音的主要因素，或者在人工耳蜗使用者的情况下， 感知音乐。尽管我们对音高是如何被感知、编码和 在我们的听觉系统中表现出来的，在我们对如何 音调，尤其是和声，在听觉皮质中被表现出来。更好地理解 涉及音调知觉的神经转换应该有助于设计更有效的神经和 声学假体。被提议的项目的总体目标是理解神经 音高和和声的表示，并阐明时间整合和和声的作用 使用行为(心理声学)和神经成像技术相结合的音调感知 (功能磁共振成像)。在要求的延长期内，我提议完成与这两个项目有关的两个项目 最重要的主题。FMRI将用于研究调和复音的特性 出现在听觉皮质的前外侧区域。使用精心控制的刺激，这项研究 应该提供强有力的证据，证明和声是否会引起比 听觉皮质中的不和谐音调。这将有助于阐明存在或不存在 在听觉皮质中有选择地对复合体的音调做出反应的整合的音调中心 听起来。我还将完成一系列的行为实验，使用一种新的刺激 产生虚幻的虚拟音调感知，以提供量化参数的经验数据 在音高感知中管理时间整合。这些行为实验将增加 对音高感知的时间方面的关键理解，这些方面在 目前的音高感知模型。这些实验的结果也将由 为补助金的R00部分计划的研究。总体而言，在该扩建项目中完成的项目 Period将把幻觉刺激的知觉特征与神经生理学发现联系起来 为音调感知领域提供新的见解，这反过来可能会推动 听觉假体中新的音调处理策略。所进行的研究和培训 在这段延长的时间内提供的服务将使我能够实现开发一个 采用神经生理学和行为学方法的独立研究计划 研究听觉现象。

PROJECT SUMMARY Pitch and harmonicity play a defining role in the perception of speech and music, and are crucial for the perceptual organization of sounds in an auditory scene. Listeners with hearing loss, and especially those with cochlear implants, suffer from a striking deficit in pitch perception abilities, as current sound processing strategies are unable to provide robust pitch cues. This lack of pitch cues is a major factor in their inability to perceive speech in noise, or in the case of cochlear implant usserss, perceive music. Despite advances in our understanding of how pitch is perceived, coded, and represented in our auditory system, there are still significant gaps in our basic understanding of how pitch, and especially harmonicity, is represented in the auditory cortex. A better understanding of the neural transformations involved in pitch perception should help in designing more effective neural and acoustic prostheses. The overall goal of the proposed project is to understand the neural representation of pitch and harmonicity and elucidate the role of temporal integration and harmonicity in pitch perception using a combination of behavioral (psychoacoustics) and neuroimaging techniques (fMRI). In the requested extension period, I propose to finish two projects related to both of these overarching themes. fMRI will be used to investigate what properties of harmonic complex tones are represented in anterior-lateral regions of auditory cortex. Using carefully controlled stimuli, this study should provide strong evidence for whether harmonic tones elicit a stronger response than inharmonic tones in auditory cortex. This would help elucidate the presence (or absence) of an integrated ‘pitch center’ in auditory cortex that is selectively responsive to the pitch of complex sounds. I will also finish conducting a series of behavioral experiments using a novel stimulus that produces an illusory virtual pitch percept, to provide empirical data for quantifying the parameters governing temporal integration in the perception of pitch. These behavioral experiments will add crucial understanding of the temporal aspects of pitch perception, which are not taken into account in current pitch perception models. The results of these experiments will also be extended by the studies planned for the R00 portion of the grant. Overall, the projects completed in this extension period will relate perceptual characterizations of the illusory stimulus to neurophysiological findings to provide new insights to the field of pitch perception, which in turn could motivate the development of novel pitch processing strategies in auditory prostheses. The research performed and training provided during this extended time period will enable me to achieve the goal of developing an independent research program that employs both neurophysiological and behavioral approaches to investigate auditory phenomena.