Functional MRI of Congnitive Processes

描述（由申请人提供）：本申请中提出的研究的总体目标是确定在执行特定空间认知任务期间人类额叶和顶叶的大脑激活模式，如高场强（4特斯拉）功能性磁共振成像（fMRI）所揭示的。将对健康的女性和男性进行研究。这些任务的目的是检验一些高阶空间认知过程是如何在额顶叶皮层中表现的假设。提出的研究集中在路由跟踪。该功能关键地取决于该皮质的完整性，如皮质损伤后（例如中风后）的皮质紊乱所证明的。路线追踪所涉及的过程包括路线段的追踪以及从一个段转向下一个段。我们将测试五个假设有关的神经代表这些过程和他们的具体方面顶叶皮层可能是工具。第一个假设是直线路段的追踪方向以有序的方式表示，使得存在追踪方向的有序地图。第二个假设是，追踪一条复杂的路线（即由多个路段组成的路线）是一个空间分布的过程，随着该过程的时间展开，该过程依次涉及额顶叶皮层的不同部分。第三个假设是，从一个片段转向下一个片段涉及这两个片段之间的心理旋转过程，因此激活的强度将取决于旋转的角度。第四个假设是，这种依赖性的激活角度的方向变化将定性和定量类似于独立的心理旋转范式中观察到的依赖性。最后，第五个假设涉及女性和男性之间的差异，与跟踪复杂序列相关的大脑激活模式以及激活对转向角度和心理旋转的依赖性。由于功能磁共振成像在高磁场下提供了足够的分辨率，即使对于个体受试者，这些目标的潜在实现也是可以实现的。将使用传统和专门的空间统计技术分析所获得的数据。预期获得的结果将提供关于大脑如何处理动态、认知、视觉过程的新见解，这些过程通常在患有皮质损伤的患者中受到干扰，例如中风后。此外，他们将提供一个洞察可能的半球不对称性和差异的妇女和男子，特别是在性能的顺序运动和心理旋转任务

DESCRIPTION (provided by applicant): The overall goal of the research proposed in this application is to determine the brain activation patterns in the human frontal and parietal lobes during performance of specific spatial cognitive tasks, as revealed by high field strength (4 Tesla) functional magnetic resonance imaging (fMRI). Healthy women and men will be studied. The tasks are designed to test hypotheses of how some higher order spatial cognitive processes are represented in the frontoparietal cortex. The research proposed is centered on route-tracing. This function crucially depends on the integrity of this cortex, as evidenced by its disturbance following cortical damage, e.g. after stroke. The processes involved in route-tracing comprise tracing of route segments as well as turning from one segment to the next. We will test five hypotheses concerning the neural representation of these processes and their specific aspects for which parietal cortex might be instrumental. The first hypothesis is that the direction of tracing of a straight route segment is represented in an orderly fashion, such that there is an orderly map of the direction of tracing. The second hypothesis is that tracing of a complex route (i.e. a route composed of multiple segments) is a spatially distributed process that sequentially engages distinct parts of the frontoparietal cortex, as the process unfolds in time. The third hypothesis is that turning from one segment to the next involves a process of mental rotation between these two segments, such that the intensity of activation will depend on the angle of rotation. The fourth hypothesis is that this dependence of the activation on the angle of directional change will be qualitatively and quantitatively similar to the dependence observed in a stand-alone mental rotation paradigm. Finally, the fifth hypothesis concerns differences between women and men with respect to the brain activation patterns associated with tracing complex sequences and the dependence of activation on the turning angle and mental rotation. The potential achievement of these objectives is within reach, due to the adequate resolution afforded by the fMRI at high magnetic field, even for individual subjects. The data acquired will be analyzed using both traditional as well as specialized spatial statistical techniques. The results to be obtained are expected to provide novel insights into how the brain deals with dynamic, cognitive, visuomotor processes that are commonly disturbed in patients suffering from cortical damage, e.g. after stroke. In addition, they will provide an insight into possible hemispheric asymmetries and differences between women and men, especially with respect to the performance of sequential movement and mental rotation tasks