Cortical representations of harmonic and virtual pitch in humans

项目摘要 音高和和声在语音和音乐的感知中起着决定性的作用，并且对于 听觉场景中声音的知觉组织。听力损失患者，以及 特别是那些植入耳蜗的人，在音高感知能力方面存在明显的缺陷， 当前的声音处理策略不能提供鲁棒的音高提示。缺乏音高提示 这是他们不能在噪声中感知语音的主要因素，或者在耳蜗植入物使用者的情况下， 感知音乐尽管我们在理解音高是如何被感知、编码和 在我们的听觉系统中，我们对听觉系统的基本理解仍然存在很大的差距。 音高，特别是和声，在听觉皮层中表现出来。更好地理解 涉及音高感知的神经转换应该有助于设计更有效的神经和 声学假体该项目的总体目标是了解神经 音高和和声性的表征，并阐明时间整合和和声性的作用 在音高感知中使用行为（心理声学）和神经成像技术的组合 （fMRI）。在请求的延长期内，我建议完成与这两个项目有关的两个项目 总体主题。功能磁共振成像将被用来研究谐波复合音的性质是什么 在听觉皮层的前外侧区域表现出来。通过仔细控制刺激，这项研究 应该提供强有力的证据，是否谐波音调引起更强的反应， 听觉皮层中不和谐的音调这将有助于阐明存在（或不存在） 听觉皮层中的一个整合的“音高中心”，对复合音的音高有选择性地作出反应 声音.我还将完成一系列的行为实验，使用一种新的刺激， 产生一个虚幻的虚拟音高感知，为量化参数提供经验数据 控制音高感知的时间整合。这些行为实验将增加 对音高感知的时间方面的重要理解，这在 当前的音高感知模型。这些实验的结果也将得到扩展， 研究计划的R00部分的赠款。总的来说，在本延长期内完成的项目 期间将涉及知觉表征的错觉刺激的神经生理学研究结果， 为音高感知领域提供了新的见解，这反过来又可以促进 听觉假体中的新音高处理策略。进行的研究和培训 在这段时间内提供的，将使我能够实现发展的目标， 一个独立的研究项目，采用神经生理学和行为学的方法， 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.