MULTISENSORY INTEGRATION IN EXTRASTRIATE VISUAL CORTEX

外纹视觉皮层的多感觉整合

• 批准号: 7661457
• 负责人: Dora Angelaki
• 金额: $ 38万
• 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/7661457
• 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; base; discount; electrical microstimulation; extrastriate visual cortex; improved; microstimulation; multisensory; novel; object motion; optic flow; preference; public health relevance; 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(申请人提供)：多个感官输入的整合是强健的感知和行为表现所必需的。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线索。当我们根据两个独立的线索做出知觉判断时，我们能够考虑每个线索的可靠性，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，当存在两个感觉线索时，行为表现会有所改善。涉及多感官整合的一项特别重要的任务是对自我运动或航向的估计。来自视觉(‘光流’)和前庭线索的信息对航向感知都是有用的，但对线索整合的原理和神经基础知之甚少。使用复杂的虚拟现实系统，我们开发了一种新的行为范式来研究猕猴的线索整合。在这里，我们建议测试关于背侧内侧上颞区(MSTd)和腹侧顶内区(VIP)在视觉/前庭线索整合中的作用的具体假设。在目标1中，我们将记录猴子在执行方向识别任务时的MSTd和VIP神经元，仅基于前庭线索，仅基于视觉线索，以及两种线索的联合呈现。我们假设，具有一致的视觉/前庭反应的MSTd/VIP神经元构成了贝叶斯线索整合的神经基础，包括当视觉可靠性发生变化时重新加权线索。在目标2中，我们将通过微刺激和可逆化学失活技术操纵神经活动，探索MSTd/VIP神经元和多感觉线索整合之间的因果联系。在目标3中，我们探索了MSTd/VIP神经元的功能作用，这些神经元具有与视觉/前庭反应相一致的相反的反应。我们将测试特定的假设，其中最突出的是具有相反视觉/前庭偏好的神经元在区分由物体运动引起的视觉运动成分与由自我运动引起的视觉运动成分方面的潜在作用。将这些目标结合起来，将在我们对多感觉皮质的理解以及更广泛地说大脑如何使用概率进行计算方面提供一个根本性的突破。我们揭示的关于感觉整合的一般原理应该在系统水平的神经科学的许多问题上有广泛的应用。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许多大脑功能障碍(包括阿尔茨海默病)常见的空间定向障碍的新策略。这些缺陷之一是从光流判断航向的能力受损，这种障碍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定向到适当的大脑区域。公共卫生相关性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许多大脑功能障碍(包括阿尔茨海默病)常见的空间定向障碍的新策略。这些缺陷之一是从光流判断航向的能力受损，这种障碍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定向到适当的大脑区域。