FMRI OF AUDITORY ATTENTION TO COMPLEX ENVIRONMENTAL SOUNDS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 这项研究的总体目标是更好地了解人类大脑皮层系统在环境声音识别和三维空间声音定位方面的组织和机制。为了实现这一目标，将使用功能磁共振成像(FMRI)来区分、绘制和功能描述(在视力正常和失明的人中)大脑区域，这些区域涉及引导注意力到三维(3D)可定位的自然声音，当参与者躺在MRI扫描仪中时，这些声音通过高保真耳机系统呈现。重点将放在(1)绘制皮层路径，优先于处理空间位置(“Where”)，而不是识别复杂自然声音的内容(“What”)。我们希望在空间注意声音的过程中激活一个特定的“额顶”网络，并在注意到相同声音刺激的内容时激活几个高水平的听觉关联区。由于我们最近在大脑皮层中发现了部分分离的通路，用于处理相对于手动工具声音(两种不同的概念类别的声音)的动物发声，我们还将确定(2)沿着这些不同通路的活动是否可以被注意力调节。这将通过提供同步声源来评估，要求参与者忽略分散注意力的声音(S)。我们还将能够确定额顶皮质网络的一部分(如上所述)是否也参与了“听觉串流”，即注意力被引导到处理一个声源，必须过滤掉另一个(S)。 志愿者将执行听觉行为任务，同时使用新升级的3Tesla General Electric Horizon HD扫描仪研究扫描仪采集功能图像，使用T2*加权功能图像的回声平面和/或螺旋成像序列。我们将使用“无声”集群式采集功能磁共振成像范例(与事件相关)，该范例旨在使高保真声音在扫描过程的无声期间直接传递到耳朵(在耳罩下)，从而最大限度地减少或消除与扫描仪噪声相关的干扰。总之，这个项目中的实验试图识别负责声音识别、空间定位和听觉注意的皮质系统，提供负责我们感知复杂自然声音中包含的不同类型信息的不同和重叠的皮质路径的详细地图。这一结果将大大推进与人类听觉处理有关的知识体系。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The overall goal of this study is to provide a better understanding of the organization and mechanism of human cortical systems involved in aspects of both environmental sound recognition and in sound localization in 3-dimensional space. To achieve this goal, functional magnetic resonance imaging (fMRI) will be used to differentiate, map and functionally characterize brain regions (in both sighted and blind people) involved in directing attention to three-dimensionally (3D) localizable natural sounds, presented over a high fidelity headphone system while participants are lying in the MRI scanner. Emphasis will be placed on (1) mapping cortical pathways preferential for processing the spatial location ("where") versus recognizing the content of the complex natural sounds ("what"). We expect to activate a specific "fronto-parietal" network during spatial attention to sound, and several high-level, auditory-association regions during attention to the content of that same sound stimulus. Due to our recent discovery of partially separate pathways in cortex for processing animal vocalizations relative to hand-manipulated tool sounds (two distinct conceptual categories of sound), we will also determine (2) if activity along these distinct pathways can be modulated by attention. This will be assessed by presenting simultaneous sound-sources, requiring the participant to ignore the distracting sound(s). We will additionally be able to determine if portions of the fronto-parietal cortical network (mentioned above), are also involved in "auditory streaming", wherein attention is directed to processing one sound-source, having to filter out the other(s). Volunteer participants will perform auditory behavioral tasks while functional images are acquired with a newly upgraded 3 Tesla General Electric Horizon HD scanner research scanner, using echo-planar and/or spiral imaging sequences for T2* weighted functional images. We will use a "silent" clustered acquisition fMRI paradigm (event-related), which is designed to allow high fidelity sound to be delivered directly to the ears (under ear muffs) during silent periods of the scanning process, thereby minimizing or eliminating interference associated with scanner noise. Together, the experiments in this project seek to identify cortical systems responsible for sound recognition, spatial localization, and auditory attention, providing detailed maps of both distinct and overlapping cortical pathways responsible for our perception of the different types of information contained in complex natural sounds. The results will significantly advance the body of knowledge pertaining to human auditory processing.