Neural mechanisms mediating visual search

介导视觉搜索的神经机制

基本信息

批准号：
9123605
负责人：
Robert Desimone
金额：
$ 37.61万
依托单位：
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-08-01 至 2017-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9123605
关键词：
Accounting Area Attention Behavior Behavioral Biological Blindness Brain Cell Nucleus Cells Child Color Complex Crowding Data Dependence Development Disease Etiology Eye Movements Feedback Food Health Inferior Laboratories Lateral Location Maps Measures Mediating Memory Methods Nervous system structure Neurons Performance Play Population Positioning Attribute Prefrontal Cortex Primates Process Property Pulvinar structure Retina Role Shapes Short-Term Memory Signal Transduction Source Stimulus Structure System Task Performances Techniques Temporal Lobe Testing Thalamic structure Time V4 neuron Visual Visual Cortex Work area V4 base design directed attention extrastriate visual cortex frontal eye fields information processing insight neural circuit neural prosthesis neuromechanism neurophysiology neuroregulation operation optogenetics relating to nervous system response visual imagery visual information visual process visual processing visual search

项目摘要

DESCRIPTION (provided by applicant): We must often search cluttered scenes for items of immediate behavioral relevance - e.g. our food, our car keys, our child, and so on. In each case, we use our memory of the object's features to effectively guide our search, so that we are not forced to inspect every object in a crowded scene individually. Efficient visual search is critical for efficient visually guided behavior. Although much is known about the biological mechanisms that underlie the ability to attend to locations, very little is known about the mechanisms underlying visual search guided by object features. We do not yet understand where the information about the relevant object features is stored in the nervous system, how that information is used to guide eye movements to inspect object that are good candidates for the searched-for item, or how the feature information modulates the information processed in our visual cortex. To design an effective neural prosthesis or to treat people with attentional disorders, we need a better understanding of feature attention in visual search at the systems level. A better understanding of feature attention will likely also give us insight into the mechanisms underlying visual working memory and visual imagery, as these related functions seem to involve at least partially overlapping neural circuits. Two key structures that may play a role in the guidance of feature attention during visual search are the prefrontal cortex and the pulvinar nucleus of the thalamus. In fact, the pulvinar may serve to relay critical feature information from prefrontal cortex to visual cortex. Our Aims are focused on these two structures, and we are guided by our preliminary data regarding their functions. In Aim 1, we will simultaneously record from neurons in Area 45 of the prefrontal cortex, the frontal eye fields (FEF) and area V4 of visual cortex during performance of a visual search task. These recordings will test hypotheses about how prefrontal cells influence the subsequent processing of object feature information in FEF and area V4. In Aim 2, we will use newly developed optogenetic techniques during performance of the same tests of feature attention used in Aim 1, to test causal hypotheses about how the prefrontal cortex influences both behavior during search and the responses of FEF and V4 neurons. The optogenetic techniques we have successfully implemented with our collaborators will allow us to suppress neural circuits at precise locations and for precise periods of time. In Aim 3, we will record simultaneously from the pulvinar, area V4, and the inferior temporal cortex during the same tests of feature attention. We will test hypotheses about how the pulvinar regulates cortical processing during feature attention, including its role in synchronizing and de-synchronizing activity in cortical population. We will then test our conclusions using the same optogenetic techniques used in Aim 2, to suppress pulvinar activity at critical times during the performance of the tasks. In total, we expect these studies to give us the best account so far of how the interactions among multiple brain structures leads to effective visual processing during attention to object features.

描述（由申请人提供）：我们经常必须搜索杂乱的场景，以了解直接行为相关性的项目 - 例如我们的食物，我们的汽车钥匙，我们的孩子等等。在每种情况下，我们都会使用对对象功能的内存来有效地指导搜索，以免我们被迫单独检查拥挤的场景中的每个对象。有效的视觉搜索至关重要有效的视觉指导行为。尽管对参加位置的能力的基础的生物学机制知之甚少，但对以对象特征为指导的视觉搜索的机制知之甚少。我们尚不了解有关相关对象特征的信息存储在神经系统中的位置，该信息如何用于指导眼动以检查对象是搜索项目的良好候选物，或者该功能信息如何调节我们的Visual Cortex中处理的信息。要设计有效的神经假体或治疗注意力障碍的人，我们需要在系统级别的视觉搜索中更好地了解功能注意力。更好地理解功能关注也可能会使我们深入了解视觉工作记忆和视觉图像的机制，因为这些相关功能似乎至少涉及部分重叠的神经回路。在视觉搜索过程中可能在特征注意力的指导中起作用的两个关键结构是丘脑的前额叶皮层和pulvinar核。实际上，Pulvinar可以将关键特征信息从前额叶皮层传达到视觉皮层。我们的目标集中在这两种结构上，我们以有关其功能的初步数据为指导。在AIM 1中，我们将同时记录前额叶皮层区域45的神经元，额叶眼场（FEF）和视觉搜索任务执行过程中Visual Cortex的区域V4。这些记录将检验有关前额叶细胞如何影响FEF和区域V4中对象特征信息的后续处理的假设。在AIM 2中，我们将在AIM 1中使用的相同特征注意测试的性能测试期间使用新开发的光遗传技术，以测试有关前额叶皮层在搜索过程中如何影响FEF和FEF和V4神经元反应的因果假设。我们与合作者成功实施的光遗传技术将使我们能够在精确的位置和精确的时间内抑制神经回路。在AIM 3中，我们将在相同的功能注意力测试中同时记录来自Pulvinar，区域V4和下颞皮层的记录。我们将测试有关pulvinar在特征注意过程中如何调节皮质加工的假设，包括其在皮质种群中同步和去同步活性中的作用。然后，我们将使用AIM 2中使用相同的光遗传学技术来测试我们的结论，以抑制任务执行过程中关键时期的脉冲活动。总的来说，我们希望这些研究能够为我们提供最佳的说法，以了解多个大脑结构之间的相互作用如何导致注意对象特征的有效视觉处理。