Polymodal sensory and attentional interaction in human cerebral cortex

该项目的最终目标是确定和描述负责我们感知能力的神经机制，以关注和整合来自多种感觉模式的信息。为此，功能性MRI将用于研究视觉和听觉运动加工背景下的多模态感觉和注意相互作用。例如，关于路过的护理运动的视觉和听觉信息如何结合在一起产生一个共同的感知？人类视觉运动的处理途径已经得到了广泛的研究，最近，听觉运动的处理途径也得到了研究。总之，这两条独立的调查路线提供了足够的信息，允许在个别科目中比较这两个系统，从而详细调查这两个系统如何相互作用。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环境下。然后，功能磁共振成像将用于描绘与听觉运动感知有关的皮层通路。这些通路将与视觉运动知觉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反应的地点。第二个目标是确定听觉和视觉运动路径之间的相互作用，这是由运动刺激同时存在于每种模态中造成的。确定与单峰反应相比，多峰刺激导致增强或抑制的部位将是特别有趣的。第三个目标是确定任务因子如何模块化两个运动路径和收敛区域的活动。目的是确定当受试者必须以不同的方式结合视觉和听觉运动信息来完成一项任务时，皮层的激活模式是如何变化的。最后的目的是确定神经系统参与控制和分配的注意刺激在不同的模式。目标将是确定在每种模式中是否存在共同或单独的系统来控制注意力。总之，这些实验的结果将提供负责听觉和视觉运动信息整合的大脑系统的详细说明。此外，这两种运动系统的比较将揭示控制所有感觉和注意系统的功能组织的更一般的原则。这些结果将直接有助于我们理解大脑病理导致的感知缺陷和注意力忽视的生理基础。

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.