Integration of MSI/fMRI Studies of Reading

描述（由申请人提供）：拟议研究的主要目标是(a)开发一个跨学科网络，解决功能性神经成像，磁源成像（MSI）和功能性磁共振成像（fMRI）两种不同方法的集成，以便(b)评估支持熟练阅读的大脑机制模型。当大脑在执行认知任务时被激活时，这些方法对涉及的空间和时间成分的敏感性不同。通过结合德克萨斯大学休斯顿分校MSI实验室的优势和哈斯金斯实验室/耶鲁大学fMRI的资源，我们将整合这两种功能性神经成像模式，并开发一个更全面的大脑机制的熟练阅读模型。该模型规定，印刷单词识别与高度组织的皮层系统的发展有关，该系统整合了单词的正字法、语音和词汇语义特征。该系统涉及左半球（LH）的两个后回路：一个背侧（颞顶叶）回路和一个腹侧（枕颞叶）回路，以及第三个回路（额下侧）。每个回路在阅读中都有不同的作用，不仅在空间上有差异，而且在时间上也有差异。研究人员提出了一系列实验，涉及30名健康成年人，他们在执行不同的阅读任务时接受MSI和fMRI成像模式，以便(A)精确确定哪些大脑区域是支持阅读的神经回路的功能组成部分；(b)确定三个假定的神经回路在各自执行的信息处理类型方面是如何不同的。我们将系统地调制对单词识别中不同组件过程的需求，以揭示每个电路处理的信息种类的差异；(c)通过整合三种类型的数据：区域激活的空间范围、不同大脑区域参与的相对时间和功能连接，确定三个回路如何实时相互作用以支持。我们还建议对这两种技术进行交叉培训，并发展一个由两个机构的研究人员组成的跨学科网络。总之，这些努力将通过直接比较和整合技术来扩大成像数据的可解释性，并导致对阅读背后的大脑机制的更详细的理论。

DESCRIPTION (provided by applicant): The primary goals of the proposed study are to (a) develop an interdisciplinary network addressing the integration of two different methodologies for functional neuroimaging, magnetic source imaging (MSI) and functional magnetic resonance imaging (fMRI) in order to (b) evaluate a model of the cerebral mechanisms that support skilled reading. These methods differ in their sensitivity to the spatial and temporal components involved when the brain is activated while performing a cognitive task. By combining the strengths of the University of Texas-Houston MSI laboratory and the resources for fMRI at the Haskins Laboratories/Yale University, both of which have published extensively on the neural mechanisms underlying reading, we will integrate these two functional neuroimaging modalities and develop a more comprehensive model of the cerebral mechanisms underlying skilled reading. This model stipulates that printed word recognition is related to the development of a highly organized cortical system that integrates orthographic, phonological and lexical-semantic features of words. This system involves two posterior circuits in the left hemisphere (LH): a dorsal (temporo-parietal) and a ventral (occipito-temporal) circuit, along with a third circuit (inferior frontal gyms). Each circuit has a different role in reading, varying not only spatially, but also temporally. A series of experiments are proposed involving 30 healthy adults who would receive both MSI and fMRI imaging modalities while performing different reading tasks in order to (a) determine precisely which brain areas are functional components of the neural circuits supporting reading; (b) determine how the three putative neural circuits differ from one another in terms of the types of information processing performed by each. We will systematically modulate demands on different component processes in word recognition to reveal differences in the kinds of information each circuit processes; and (c) determine how the three circuits interact with each other in real time to support by integrating three types of data: spatial extent of regional activation, relative timing of the engagement of different brain areas, and functional connectivity. We also propose cross training in the two technologies and the development of an interdisciplinary network composed of investigators at both institutions. Together these efforts will expand the interpretability of imaging data by direct comparison and integration of the techniques and lead to a more elaborated theory of the cerebral mechanisms underlying reading.