Polymodal sensory and attentional interaction in human cerebral cortex

该项目的最终目标是识别和表征负责我们感知能力的神经机制，以关注和整合来自多种感官形式的信息。为此，功能磁共振成像将被用来调查多模态的感觉和注意力的相互作用，在视觉和听觉运动处理的背景下。例如，关于一辆经过的汽车的运动的视觉和听觉信息是如何结合在一起产生一个共同的感知的？人类视觉运动处理的通路已经被广泛研究，最近，听觉运动通路也在研究之中。这两个独立的调查路线共同提供了足够的信息，使这两个系统能够在单个受试者中进行比较，从而详细调查这两个系统如何交互。该项目有四个具体目标。第一个目的是记录听觉运动感知的心理物理学，特别是在MRI环境中。功能磁共振成像将被用来描绘参与听觉运动知觉的皮层通路。这些通路将与视觉运动感知过程中激活的通路进行比较。一个具体的目标将是确定两个途径汇合产生多模态响应的站点。第二个目的是确定听觉和视觉运动路径之间的相互作用，导致在每种方式的运动刺激的同时存在。与单峰反应相比，识别多峰刺激导致增强或抑制的部位将特别感兴趣。第三个目标是确定任务因素如何模块的活动在两个运动路径和收敛的领域。目标是确定当受试者必须以不同的方式结合联合收割机视觉和听觉运动信息来完成一项任务时，皮层激活模式如何变化。最后的目的是确定神经系统参与控制和分配注意力的刺激，在不同的方式。我们的目标是确定是否有共同的或单独的系统来控制每种模式的注意力。总之，这些实验的结果将提供负责整合听觉和视觉运动信息的大脑系统的详细说明。此外，对这两种运动系统的比较将揭示支配所有感觉和注意系统的功能组织的更普遍的原则。这些结果将直接有助于我们理解知觉缺陷和注意忽视的生理基础，导致大脑病理。

The ultimate goal of this project is to identify and characterize the neural mechanisms responsible for our perceptual abilities to attend to, and integrate, information from multiple sensory modalities. To this end, functional MRI will be used to investigate polymodal sensory and attentional interactions in the context of visual and auditory motion processing. For example, how does visual and auditory information about the motion of a passing care come together to yield a common percept? The pathways for visual motion processing in the human have been studied extensively and, recently, the auditory motion pathways have been under investigation. Together, these two separate lines of inquiry provide sufficient information to allow the two systems to be compared within individual subjects and, thereby, to investigate in detail how the two systems interact. The project has four specific aims. The first aim is to document the psychophysics of auditory motion perception, especially in the MRI environment. fMRI will then be used to delineate the cortical pathways involved in auditory motion perception. These pathways will be compared with the pathways activated during visual motion perception. A specific goal will be to identify sites where the two pathways converge to yield polymodal responses. The second aim is to identify interactions between the auditory and visual motion pathways resulting from the simultaneous presence of motion stimuli in each modality. Identifying sites where polymodal stimulation results in either enhancement or suppression compared to the unimodal response will be of particular interest. The third aim is to determine how task factors module the activity in the two motion pathways and in areas of convergence. The goal is to determine how the cortical activation patterns change when the subject must combine visual and auditory motion information in different ways to complete a task. The final aim is to identify the neural systems involved in control and allocation of attention to stimuli in the different modalities. The goal will be to determine if there are common or separate systems for controlling attention in each modality. Together, the results of these experiments will provide a detailed accounting of the brain systems responsible for the integration of auditory and visual motion information. Moreover, the comparison of the two motion systems will reveal more general principles governing the functional organization of all the sensory and attentional systems. These results will contribute directly to our understanding of the physiological basis of perceptual defects and attentional neglect resulting from brain pathology.