Neural Correlates of Auditory, Visual, and Audiovisual Motion Perception in Macaque Extrastriate Cortex

项目摘要 我们的世界是高度多感官的，我们通过许多不同的感官获取有关它的信息 系统.通常，对象或事件是由多个单一意义指定的，并且这种意义的集成 多感官信息赋予了强大的和适应性的感知和行为优势，如更快地 更准确的回答。这些优势在导航复杂环境时变得至关重要， 运动是无处不在的，就像在真实的世界中一样。然而，多感觉处理也呈现出一种 对大脑的计算挑战：为了有效地执行它，大脑不仅需要决定哪些部分， 的感官信息属于同一事件（因此应该是整合或绑定），但也 信息需要隔离。尽管近年来在进一步促进我们的 多感官知觉及其神经相关的理解，我们仍然有显着的差距， 关于处理更多生态有效刺激的知识，例如包含运动的刺激。之一 这些差距围绕着运动信息如何在存在调制性、跨模态 输入，因为它使其通过皮层处理层次结构的连续阶段的方式，以及这些 转换映射到行为/感知。本提案中概述的实验开始， 用我们已经开发的行为范例来解决这个问题，在这些范例中，猕猴发出方向信号， 听觉、视觉或视听运动刺激。在执行任务期间，我们将记录神经元 两个皮层区域的活动反映了处理层次中的连续水平：内侧颞叶 (MT)和内侧上级颞（MST）区。第一个目标是研究模态和运动强度 在视听刺激影响歧视行为，并有助于因果推理。第二 aim试图描述这些区域对听觉、视觉和视听运动信息的反应， 总体假设，随着运动信息从MT上升到MST， 调节性听觉输入的作用，反映了从编码低水平刺激特征的逐渐转变 例如朝向与目标导向行为相关的特征的编码的信号强度 方向和任务要求。总的来说，这项工作将大大阐明 多感官知觉对运动处理至关重要。此外，这些实验的成功 将挑战我们对感觉皮层处理层次模块化的看法。等 由于人们越来越认识到这些人的多感觉功能改变， 神经发育状况和/或感觉功能丧失，以及大脑信息的价值 自然主义虚拟和增强现实技术的算法。

PROJECT SUMMARY Our world is highly multisensory, and we acquire information about it via a number of distinct sensory systems. Typically, objects or events are specified by more than a single sense, and the integration of this multisensory information confers powerful and adaptive perceptual and behavioral advantages such as faster and more accurate responses. These advantages become pivotal when navigating complex environments where motion is ubiquitous, as is the case in the real world. However, multisensory processing also presents a computational challenge for the brain: to carry it out efficiently, the brain needs to not only decide which pieces of sensory information belong to the same event (and thus should be integrated or bound), but also which information needs to be segregated. Although great strides have been made in recent years to further our understanding of multisensory perception and its neural correlates, there are still significant gaps in our knowledge with regards to processing more ecologically-valid stimuli, such as those containing motion. One of these gaps revolves around how motion information is transformed in the presence of modulatory, cross-modal input as it makes its way through successive stages of the cortical processing hierarchy, and how these transformations map on to behavior/perception. The experiments outlined in the current proposal begin to address this issue using behavioral paradigms that we have developed in which macaques signal the direction of an auditory, visual, or audiovisual motion stimulus. During performance of the task, we will record neural activity in two cortical domains reflecting successive levels in the processing hierarchy: the medial temporal (MT) and medial superior temporal (MST) areas. The first aim will examine how modality and motion strength within audiovisual stimuli impact discrimination behavior and contribute towards causal inference. The second aim seeks to characterize responses to auditory, visual, and audiovisual motion information in these areas with the overarching hypothesis that as motion information ascends from MT to MST, there will be an increase in the role of modulatory auditory input, reflective of a gradual shift from encoding low-level stimulus features such as signal strength toward the encoding of features relevant to goal-oriented behavior such as stimulus direction and task demands. Collectively, the work will shed great light on the mechanistic underpinnings of multisensory perception in nodes critical to motion processing. Additionally, success in these experiments would challenge how we think about the modularity of the sensory cortical processing hierarchy. Such knowledge is of increasing importance given the growing recognition of altered multisensory function in those with neurodevelopmental conditions and/or sensory function loss, as well as the value of brain-informed algorithms for naturalistic virtual and augmented reality technology.