MULTISENSORY INTEGRATION IN EXTRASTRIATE VISUAL CORTEX

外纹视觉皮层的多感觉整合

• 批准号: 7892453
• 负责人: Dora Angelaki
• 金额: $ 37.62万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7892453
• 关键词: Accounting; Alzheimer' s Disease; Animal Model; Area; Behavioral; Behavioral Paradigm; Brain; Brain region; Cells; Chemicals; Cues; Darkness; Data; Discrimination; Disorientation; Dorsal; Exhibits; Functional disorder; Goals; Head; Human; Impairment; Judgment; Light; Link; Macaca; Macaca mulatta; Medial; Mediating; Monkeys; Motion; Motion Perception; Nature; Neurons; Neurosciences; Patients; Perception; Performance; Primates; Probability; Probability Theory; Process; Psychophysiology; Relative (related person); Reporting; Role; Rotation; Saccades; Scheme; Sensory; Signal Transduction; Simulate; Stimulus; System; Techniques; Testing; Time; Training; Translations; Visual; Visual Motion; Weight; abstracting; base; discount; electrical microstimulation; extrastriate visual cortex; improved; microstimulation; multisensory; novel; object motion; optic flow; preference; receptive field; relating to nervous system; research study; response; sample fixation; sensory integration; theories; ventral intraparietal area; virtual reality; visual optics; visual-vestibular

DESCRIPTION (provided by applicant): Integration of multiple sensory inputs is required for robust perception and behavioral performance. Recent psychophysical studies indicate that humans combine cues according to a statistically optimal weighting scheme derived from Bayesian probability theory. When we make perceptual judgments that rely on two separate cues, we are able to take into account the reliability of each cue, even when this reliability varies randomly from trial to trial. Bayesian theory also predicts an improvement in behavioral performance when two sensory cues are present, as compared with only one cue. One particularly vital task that involves multisensory integration is the estimation of self-motion, or heading. Information from both visual (`optic flow') and vestibular cues can be useful for heading perception, yet little is known about the principles and neural substrates for cue integration. Using a sophisticated virtual reality system, we have developed a novel behavioral paradigm for studying cue integration in rhesus monkeys. Here we propose to test specific hypotheses regarding a role of the dorsal medial superior temporal area (MSTd) and ventral intraparietal area (VIP) in visual/vestibular cue integration. In aim 1, we will record from MSTd and VIP neurons while the monkey performs a heading discrimination task, based on vestibular cues alone, visual cues alone and combined presentation of both cues. We hypothesize that MSTd/VIP neurons with `congruent' visual/vestibular responses constitute a neural substrate for Bayesian cue integration, including cue re-weighting when visual reliability changes. In aim 2, we will probe for causal links between MSTd/VIP neurons and multi-sensory cue integration for heading perception by manipulating neural activity using microstimulation and reversible chemical inactivation techniques. In aim 3, we explore the functional roles of MSTd/VIP neurons having `opposite', as compared to `congruent', visual/vestibular responses. We will test specific hypotheses, the most prominent of which is a potential role of neurons with opposite visual/vestibular preferences on disambiguating the components of visual motion that are due to object motion from those due to self-motion. Combined these aims will provide a fundamental breakthrough in our understanding of multisensory cortex, as well as more generally how the brain computes using probabilities. The general principles that we uncover regarding sensory integration should have wide application to many issues in systems-level neuroscience. Understanding the neural basis of multisensory integration and self-motion perception would also promote new strategies for treating spatial disorientation deficits common to many brain dysfunctions, including Alzheimer's disease. One of these deficits is an impaired ability to judge heading from optic flow, and this impairment is correlated with patients' difficulty in navigating through their surroundings. Better localization of these functions in a primate animal model would help targeting new Alzheimer's therapies to the appropriate brain regions. PUBLIC HEALTH RELEVANCE Understanding the neural basis of multisensory integration and self-motion perception would also promote new strategies for treating spatial disorientation deficits common to many brain dysfunctions, including Alzheimer's disease. One of these deficits is an impaired ability to judge heading from optic flow, and this impairment is correlated with patients' difficulty in navigating through their surroundings. Better localization of these functions in a primate animal model would help targeting new Alzheimer's therapies to the appropriate brain regions.

描述（由申请人提供）：强大的感知和行为表现需要多个感官输入的整合。最近的心理物理学研究表明，人类根据贝叶斯概率理论得出的统计最优加权方案来组合联合收割机线索。当我们依靠两个独立的线索做出知觉判断时，我们能够考虑到每个线索的可靠性，即使这种可靠性在不同的试验中随机变化。贝叶斯理论还预测，与只有一个线索相比，当存在两个感官线索时，行为表现会有所改善。一个涉及多感觉整合的特别重要的任务是估计自我运动或航向。来自视觉（“光流”）和前庭线索的信息可以用于航向感知，但对线索整合的原理和神经基质知之甚少。使用一个复杂的虚拟现实系统，我们已经开发了一种新的行为范式研究线索整合恒河猴。在这里，我们建议测试特定的假设，背内侧上级颞区（MSTd）和腹侧顶内区（VIP）的视觉/前庭线索整合的作用。在目标1中，我们将记录从MSTd和VIP神经元，而猴子执行的标题歧视任务，基于前庭线索单独，视觉线索单独和两种线索的组合呈现。我们假设，MSTd/VIP神经元与“一致”的视觉/前庭反应构成了贝叶斯线索整合，包括线索重新加权时，视觉可靠性的变化神经基板。在目标2中，我们将探索MSTd/VIP神经元和多感觉线索整合的标题知觉通过操纵神经活动，使用微刺激和可逆的化学失活技术之间的因果关系。在目标3中，我们探讨了MSTd/VIP神经元具有“相反”的功能作用，相比“一致”，视觉/前庭反应。我们将测试具体的假设，其中最突出的是一个潜在的作用，神经元相反的视觉/前庭偏好上的歧义的视觉运动的组成部分，是由于对象的运动，由于自我运动。这些目标的结合将为我们对多感觉皮层的理解提供一个根本性的突破，以及更普遍的大脑如何使用概率进行计算。我们所发现的感觉统合的一般原理应该对系统层次神经科学的许多问题有广泛的应用。了解多感觉整合和自我运动感知的神经基础也将促进治疗空间定向障碍缺陷的新策略，这些缺陷常见于许多脑功能障碍，包括阿尔茨海默病。这些缺陷之一是从光流判断航向的能力受损，这种损伤与患者在周围环境中导航的困难有关。在灵长类动物模型中更好地定位这些功能将有助于将新的阿尔茨海默氏症疗法靶向适当的大脑区域。了解多感觉整合和自我运动感知的神经基础也将促进治疗空间定向障碍缺陷的新策略，这些缺陷是许多脑功能障碍（包括阿尔茨海默病）所常见的。这些缺陷之一是从光流判断航向的能力受损，这种损伤与患者在周围环境中导航的困难有关。在灵长类动物模型中更好地定位这些功能将有助于将新的阿尔茨海默氏症疗法靶向适当的大脑区域。