Functional Microcircuits of Sensory Neocortex

大脑新皮质在感知、行动和高级认知过程中起着至关重要的作用，这导致了人们对这一组织的功能特性的深入了解。这项工作的主要目标是阐明单个皮质神经元获得不同反应特性的机制，以及皮质神经元群体如何相互作用以产生整体感知和行为能力。这项拟议的研究在兔子身上进行，旨在了解清醒的、完整的丘脑皮质躯体感觉系统中控制皮质功能的机制。这项工作旨在了解皮质内回路对丘脑皮质输入执行的转换，产生这些转换的前馈抑制神经元间蛋白的作用，以及这些转换如何导致平行和不同的传出流出。使用新的多电极方法，将同时记录丘脑皮质投射神经元的活动、皮质输出(投射神经元)和可能的抑制性中间神经元，并将使用互相关和微刺激的方法分析这些已识别元素之间的相互作用。配对的皮质内记录(细胞内/细胞外)也将提供关于中间神经元与其邻近的皮质内靶点之间相互作用的信息。将特别强调理解：(A)支配所研究的丘脑皮质和皮质神经元群体之间功能联系的特异性的规则，以及(B)皮质内前馈抑制的潜在机制。从这些实验中获得的数据将为在自然条件下研究单个皮质神经元的生理学提供一个独特的视角，并将为深入了解皮质神经元的相互作用网络及其不同的功能特性提供洞察。如果我们想要了解大脑皮层网络如何产生感知、行动和高级认知过程，这些信息是必不可少的。

The cerebral neocortex plays a crucial role in perception, action and higher cognitive processes and this has led to an intense effort to understand the functional properties ofthis tissue. Major goals of this effort have been to elucidate the mechanisms whereby individual cortical neurons obtain their diverse response properties and how ensemblesof cortical neurons interact to produce global perceptual and behavioral capabilities. The proposed research, conducted in the rabbit, is aimed at understanding themechanisms governing cortical function in the awake, intact, thalamocortical somatosensory system. The work is aimed at understanding the transformations performed upon thalamocortical inputs to the cortex by the intracortical circuitry, the role of feed-forward inhibitory interneuronsin producing these transformations, and how these transformations lead to parallel and distinct efferent outflows. Using novel multi-electrode methodology, the activity of thalamocortical projection neurons, cortical output (projection neurons), and putative inhibitory interneurons will be simultaneously recorded, and interactions among these identified elements will be analyzed using methods of cross-correlation and microstimulation. Paired intracortical recordings (intracellular/extracellular) will also yield information about interactions between interneurons and their neighboring intracortical targets. Special emphasis will be placed on understanding: (a) the rules governing the specificity of functional connections among the populations of thalamocortical and cortical neurons under study, and (b) the mechanisms underlying feed-forward intracorticalinhibition. The data obtained from these experiments will offer a unique view of the physiology of individual cortical neurons studied under natural conditions, and will provide insight into interactive networks of cortical neurons and their varied functional properties. Such information isessential if we are to understand how neocortical networks generates perception, action, and higher cognitive processes.