Cortical synaptic circuitry underlying visual processing

视觉处理的皮层突触电路

• 批准号: 8539625
• 负责人: Huizhong Whit Tao
• 金额: $ 45.94万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-30 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8539625
• 关键词: Accounting; Address; Cells; Development; Equilibrium; Exhibits; Generations; Image; Individual; Label; Lead; Mental disorders; Methods; Modeling; Molecular Genetics; Motion Perception; Mus; Neurons; Optics; Parvalbumins; Pathology; Pattern; Perception; Physiology; Property; Relative (related person); Role; Sensory Process; Shapes; Signal Transduction; Source; Stimulus; Structure; Subgroup; Synapses; Techniques; Testing; Thalamic structure; Transgenic Mice; Visual Cortex; base; cell type; excitatory neuron; in vivo; information processing; inhibitory neuron; innovation; insight; mouse model; nervous system disorder; neural circuit; optogenetics; orientation selectivity; presynaptic; receptive field; relating to nervous system; research study; response; spatiotemporal; tool; two-photon; visual process; visual processing; visual stimulus; voltage clamp

DESCRIPTION (provided by applicant): The cortical processing of sensory information depends critically on the orchestrated activity of interconnected excitatory and inhibitory neurons. Understanding the structure of these excitatory and inhibitory synaptic circuits is key for comprehending how information processing is achieved in the cortex, but the progress has been limited previously by technical difficulties in bridging connectivity and function. The recent development of molecular and genetic tools in the mouse makes it an attractive model for systematically dissecting synaptic circuitry underlying cortical functions. Taking advantage of these tools, we will be able to integrate multiple approaches to address synaptic circuitry mechanisms for the fundamental receptive field properties of mouse primary visual cortical neurons. In this project, we will first reveal the spatiotemporal interplays of visually evoked excitatory and inhibitory synaptic inputs to excitatory neurons with in vivo whole-cell voltage-clamp recordings. Specifically, we will determine the synaptic mechanisms underlying two fundamental visual processing properties of cortical excitatory neurons, the directional selectivity and the contrast invariance of orientation selectivity. We will then dissect the functional contribution of excitatory inputs from different origins with optogenetic methods. By silencing the cortex with optogenetic activation of a specific group of inhibitory neurons, we will determine the respective contribution of thalamocortical and intracortical input to orientation selectivity of layer 4 excitatory neurons. Finally, by developing two-photon imaging guided whole-cell voltage-clamp recording techniques in transgenic mouse models, we will determine the synaptic mechanisms for the weak orientation tuning exhibited by pavalbumin-positive cortical inhibitory neurons. These proposed studies will potentially provide important new insights into how functional cortical synaptic circuits are organized and how cortical processing and sensory perception may go awry under neurological disease conditions which result in disrupted excitation-inhibition balance.

描述（由申请人提供）：感觉信息的皮质处理主要依赖于相互连接的兴奋性和抑制性神经元的协调活动。了解这些兴奋性和抑制性突触回路的结构是理解信息处理如何在皮层中实现的关键，但由于连接和功能之间的桥接技术困难，先前的进展受到限制。最近的