Mapping the intrinsic functional organization of auditory cortex in individual subjects using 7T MRI

用7T磁共振成像研究个体听觉皮质的固有功能组织 尽管有无数的研究，但目前只有更广泛的人类听觉皮质(AC)的处理流 为人所知。缺乏一个被广泛接受的人类急性冠脉综合征模型，类似于在非人类灵长类动物中描述的模型， 导致了关于人脑声音处理的基本理论分歧。更好 对人类急性冠脉综合征的了解对于开发生物标记物和干预治疗至关重要。 涉及听觉处理缺陷以及言语和语言障碍的障碍。 人类急性冠脉综合征的研究由于独特的技术障碍而变得复杂，例如他们的小解剖学 在常规分辨率下阻碍功能磁共振研究的规模。然而，在理论上也有重要的 为什么急性冠脉综合征比其他感觉区域更难标测：与早期视觉皮质相比，人类 AC由更广泛的特征组合激活，并在解剖上显示出更大的个体间变异性 和功能。人类ACS可以构成更高级别的处理，而不仅仅是特定于特征的区域 中心，这是支持日益复杂的听觉技能所必需的，这些技能仅在人类中进化。 要实现对人类听觉认知的更基本的理解，需要一个新的视角， 它考虑了人类ACS作为一个整体是如何工作的，并与人脑的其他部分相互作用。这 呼吁采用适合于动态功能网络的个体水平研究的技术，而不是群体分析 功能磁共振定位仪数据。不幸的是，到目前为止，还缺乏这样的技术。 该项目结合了先进的计算分析和超高分辨率的7T fMRI，以实现 一种全新的方法来描述人类AC在个体受试者中的功能组织。我们的 拟议的工作建立在我们实验室的最新革命性进展的基础上，这使得我们能够专注于个人 使用超高分辨率7T磁共振成像研究受试者和动态功能活动模式。我们将用这些小说 研究(A)静息状态和(B)复合听觉刺激期间AC活动的技术，以及(C)比较 其结果以传统的金标、色调和带宽敏感度图为主。要精确地映射 AC的功能组织在个别受试者中，我们将使用亚毫米分辨率的7T fMRI，并辅之以 具有先进的皮质折叠模式、厚度和皮质内髓鞘含量的解剖MRI分析。 FMRI结果将使用术前患者的颅内脑电数据进行验证。这些方法将是 用于在单个受试者中定位ACS的细粒子区(目标1)，表征AC的共同激活 分布的但特定于刺激类别的模式(目标2)，最后检查个体的可变性 并将其与听觉认知能力进行比较(目标3)。

Mapping the intrinsic functional organization of auditory cortex in individual subjects using 7T MRI Despite countless studies, only broader processing streams of the human auditory cortex (AC) are currently known. The lack of a widely accepted model of human ACs, analogous to that described in non-human primates, has contributed to fundamental theoretical disagreements on sound processing in the human brain. Better understanding of human ACs is crucial for the development of biomarkers and interventions for disorders involving auditory processing deficits and speech and language impairments. Studies of human ACs have been complicated by unique technical barriers, such as their small anatomical scale that hinders fMRI studies at conventional resolutions. However, there are also theoretically important reasons why ACs have been harder to map than other sensory areas: Compared to early visual cortices, human ACs are activated by broader combinations of features and show larger inter-individual variability in anatomy and function. Instead of a feature-specific area only, human ACs could constitute a higher-level processing center, which is needed to support the increasingly complex auditory skills that have evolved in humans only. Achieving a more fundamental understanding of human auditory cognition requires a novel perspective, which considers how human ACs work as a whole and interact with the rest of the human brain. This calls for techniques suited for individual-level studies of dynamic functional networks, instead of group analyses of fMRI localizer data. Unfortunately, to date, such techniques have been lacking. This project combines advanced computational analyses and ultra-high resolution 7T fMRI, to achieve an entirely novel way to characterize the functional organization of human AC in individual subjects. Our proposed work is built on recent revolutionary advances in our laboratories that allow focusing on individual subjects and dynamic functional activity patterns using ultra-high resolution 7T MRI. We will use these novel techniques to study AC activity during (a) the resting state and (b) complex auditory stimulation, and (c) compare the results to the traditional gold standard, tonotopy and bandwidth sensitivity mapping. To precisely map the functional organization of AC in individual subjects, we will use sub-millimeter resolution 7T fMRI, complemented with advanced anatomical MRI analyses of cortical folding patterns, thickness, and intracortical myelin content. fMRI results will be validated using intracranial EEG data from pre-operative patients. These methods will be utilized to localize fine-grained subareas of ACs in individual subjects (Aim 1), characterize AC co-activation patterns that are distributed but stimulus-category specific (Aim 2), and finally to examine the individual variability of the functional arrangement of ACs and compare it to auditory-cognitive abilities (Aim 3).