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，解决两种不同的功能神经成像方法的整合，即磁源成像(MSI)和功能磁共振成像(FMRI)，以便(B)评估支持熟练阅读的大脑机制的模型。当大脑在执行认知任务时被激活时，这些方法对所涉及的空间和时间成分的敏感度不同。通过结合德克萨斯大学休斯顿MSI实验室的优势和哈斯金斯实验室/耶鲁大学功能磁共振的资源，这两个实验室都发表了大量关于阅读背后的神经机制的文章，我们将整合这两种功能神经成像模式，并开发出一个更全面的熟练阅读背后的大脑机制模型。该模型规定，印刷词识别与高度组织的皮质系统的发展有关，该系统整合了单词的拼写、语音和词汇语义特征。该系统涉及左半球的两个后部环路：背侧(顶叶)和腹侧(枕颞部)环路，以及第三环路(额叶下回)。每个回路在阅读中扮演着不同的角色，不仅在空间上不同，而且在时间上也不同。计划对30名健康成年人进行一系列实验，他们在执行不同的阅读任务时同时接受MSI和fMRI成像，目的是(A)准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进行信息处理的类型方面有何不同。我们将系统地调节单词识别中不同成分加工的需求，以揭示每个电路处理的信息种类的差异；以及(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，确定三个电路如何实时相互作用以提供支持。我们还建议对这两项技术进行交叉培训，并发展一个由两个机构的调查人员组成的跨学科网络。这些努力将通过直接比较和整合这些技术来扩展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.