Pre-surgical Language Mapping with fMRI using a Natural Viewing Condition

描述（由申请人提供）：重要功能区域（感觉、运动或语言）附近病变的患者在计划或执行手术治疗时面临特殊挑战。因此，了解个体的结构功能组织以及与病变的关系对于手术计划至关重要。目前，功能磁共振成像（fMRI）已成为最广泛采用的非侵入性方法，以确定个人的功能解剖，以指导神经外科决策。传统的功能磁共振成像映射语言功能需要病人执行精确的时间和认知控制的语言任务。由于语言功能组织的复杂性和多变性，迄今为止，还没有达成共识的最佳任务范式，可以可靠和完整地识别语言敏感区域。此外，为了提高功能磁共振成像的预测价值，患者通常会接受一组任务，这些任务对他们来说可能很难理解和执行。 该项目旨在开发一种新的功能磁共振成像范式，可以通过使用自然的观看条件有效地映射个人的语言功能，其中患者只需要观看一个有趣的电影片段。基于最近的研究发现，当个体观看由时变的语言内容组成的同一个电影片段时，初级感觉运动区和联想区对自然刺激的反应是可靠的和选择性的，该假设是功能语言区的时间反应在个体之间也是高度同步的（对话、画外音、场景设置），并且通过检测哪些大脑区域表达类似的时间响应，甚至可以在神经外科患者中检测到潜在的扭曲或重组的语言区域。我们将从健康受试者和语言皮层或附近病变的脑肿瘤患者中获得电影观看和基于任务的语言功能磁共振成像。该项目的目标是：（1）研究健康受试者假定语言区的BOLD反应，提取可靠且同步的时间轮廓，建立语言反应模型。（2）通过比较不同的分析方法，发展一种分析策略，以使用语言反应模型检测个体受试者的语言区，（3）通过与基于任务的功能磁共振成像（fMRI）的比较，以及与金标准侵入性语言映射（gold standard invasive language mapping）在脑肿瘤患者中的验证，评价其有效性。 与基于任务的功能磁共振成像相比，这种要求较低的模式将更容易为患者执行（特别是那些预先存在的神经缺陷），更容易为技术人员管理， 而且通过一次简单的功能磁共振成像采集来研究自然语言功能，更省时、更划算。探索这一新的范例需要开发和测试的复杂的信号处理技术，将根据这一建议。

DESCRIPTION (provided by applicant): Patients with lesions near important functional regions (sensory, motor, or language) pose a particular challenge when planning or executing surgical treatment. Thus, understanding of the individual structural-functional organization and the relationship to the lesion is crucial for surgical planning. Currently functional magnetic resonance imaging (fMRI) has become the most broadly adopted non-invasive method to identify individual functional anatomy to guide neurosurgical decision- making. Conventional fMRI for mapping language function requires that the patient perform precisely timed and cognitively controlled language tasks. Due to the complex and variable organization of language function, to date, there is no consensus on optimal task paradigms that can reliably and completely identify language-sensitive regions. In addition, to improve the predictive value of fMRI, patients usually undergo a panel of tasks, which can be difficult for them to understand and perform. This project aims to develop a novel fMRI paradigm that can effectively map individuals' language function by using a natural viewing condition, where patients only need to watch an entertaining movie clip. Based on recent studies which have found reliable and selective responses in primary sensory-motor and association areas with naturalistic stimuli, the hypothesis is that the temporal responses within functional language areas are also highly synchronized across individuals when they watch the same movie clip consisting of time-varying linguistic content (dialogue, voice over, scene setting), and by detecting which brain areas express similar temporal responses even potentially distorted or reorganized language areas can be detected in neurosurgical patients. We will acquire movie-watching and task-based language fMRIs from healthy subjects and brain tumor patients with lesions in or near language cortex. The objectives of this project are: (1) To investigate BOLD responses from putative language areas of healthy subjects, and extract reliable and synchronized temporal profiles to build language response model, (2) To develop an analysis strategy by comparing different analytic approaches for detecting language areas in individual subjects using the language response model, and (3) To evaluate the effectiveness by comparing with task-based fMRI, and validating against gold-standard invasive language mapping in brain tumor patients. Compared with task-based fMRI, this less-demanding paradigm will be easier for patients to perform (especially those with pre-existing neurological deficits), easier for technologists to administer, and more time- and cost-effective by studying natural language function with only one simple fMRI acquisition. Exploration of this novel paradigm requires development and testing of sophisticated signal processing techniques which will be developed under this proposal.