FUNCTIONAL PROPERTIES OF NEURONAL CIRCUITS FOR VISION

视觉神经回路的功能特性

• 批准号: 8357242
• 负责人: W MARTIN USREY
• 金额: $ 2.52万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8357242
• 关键词: Affect; Attention; California; Categories; Cells; Disease; Environment; Feedback; Funding; Goals; Grant; National Center for Research Resources; Neurons; Pathway interactions; Population; Primates; Principal Investigator; Property; Research; Research Infrastructure; Resources; Role; Sensory; Series; Source; Testing; Thalamic structure; United States National Institutes of Health; Vision; corticogeniculate; cost; directed attention; falls; feeding; information processing; magnocellular; parvocellular; receptive field; research study; response; sensory system; transmission process; visual process; visual processing; visual stimulus

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. For sensory systems, feed forward projections from thalamic relay cells provide the cortex with information about the external environment. The cortex, in turn, sends extensive feedback to thalamic relay cells. The cortex thus functions both to process information supplied by the thalamus as well as to influence dynamically the transmission of thalamic input. The primary goal of the experiments presented in this proposal is to determine the functional organization of corticogeniculate feedback projections and their influence on visual processing. The proposed study involves four sets of experiments. The first major series of experiments (Specific Aim 1) will test the hypothesis that the corticogeniculate pathway contains physiologically distinct populations of neurons that selectively innervate the magnocellular and parvocellular layers of the LGN. The remaining experiments will examine the functional role of corticogeniculate projections during visual processing. In general, proposed roles for corticogeniculate function fall into two broad categories: (1) the corticothalamic pathway serves to sharpen the receptive field properties of thalamic neurons, and (2) the corticothalamic pathway serves to enhance the transmission of sensory information from periphery to cortex. The second series of experiments (Specific Aim 2) will therefore test the hypothesis that corticogeniculate feedback sharpens LGN receptive fields by suppression from the extraclassical receptive field. The third series of experiments (Specific Aim 3) will test the hypothesis that corticogeniculate feedback adjusts non-spatial aspect of LGN responses. Finally, the fourth series of experiments (Specific Aim 4) will compare the effects of directed attention on corticogeniculate neurons and LGN neurons in order to test the hypothesis that attention and the corticogeniculate pathway influence the gain of LGN responses to visual stimuli. Given the central importance of corticothalamic pathways for governing the excitability of thalamocortical networks, it is important that we understand the functional properties of the corticothalamic pathway, as disorders of the pathway likely underlie several illnesses affecting vision and visual processing.

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 对于感觉系统，来自丘脑中继细胞的前馈投射为皮层提供关于外部环境的信息。反过来，皮层向丘脑中继细胞发送广泛的反馈。因此，皮层既能处理丘脑提供的信息，又能动态地影响丘脑输入的传递。本实验的主要目的是确定皮质膝状体反馈投射的功能组织及其对视觉处理的影响。这项研究包括四组实验。第一个主要系列的实验（具体目标1）将测试的假设，皮质膝状体通路包含生理上不同的神经元群体，选择性地支配大细胞和小细胞层的LGN。剩下的实验将研究皮质膝状体投射在视觉加工过程中的功能作用。一般来说，皮质膝状体功能的作用分为两大类：（1）皮质丘脑通路用于锐化丘脑神经元的感受野特性，（2）皮质丘脑通路用于增强感觉信息从外周到皮质的传递。因此，第二系列实验（具体目标2）将测试的假设，即皮质膝状体反馈锐化LGN感受野的抑制，从extraclassical感受野。第三个系列的实验（具体目标3）将测试的假设，皮质膝状体反馈调节非空间方面的LGN反应。最后，第四系列实验（具体目标4）将比较定向注意对皮质膝状体神经元和LGN神经元的影响，以检验注意和皮质膝状体通路影响LGN对视觉刺激的反应增益的假设。鉴于皮质丘脑通路对于控制丘脑皮质网络的兴奋性的核心重要性，我们理解皮质丘脑通路的功能特性是很重要的，因为该通路的紊乱可能是影响视觉和视觉处理的几种疾病的基础。