STRUCTURE/FUNCTION RELATIONSHIPS IN VISUAL CORTEX

这项研究计划的长期目标是了解 构成信息基础的结构/功能关系 外侧膝状核(LGN)和视觉的加工 大脑皮层，以及两个大脑区域之间的相互关系。 这里提出的实验将解决关于细胞的问题 LGN中存在的类型，影响其 信号处理，以及视皮层中细胞的连接。 这些实验的推动力是发现了一种新型的X- LGN A层中的中继细胞(术语滞后，或X细胞)，其 功能和结构特性不同于其他X继电器 细胞(称为非滞后细胞或X细胞)，它们似乎反映了 基因内抑制机制与细胞结构有关。 目前的目标是了解更多关于生理和 这两个膝状X细胞群的形态特征和 以确定从他们那里接收到的皮质细胞。这个 Y细胞的属性和投射，可能还包含 落后组和非落后组也将接受检查。 具体目标如下：(1)进一步明确 对滞后和非滞后LGN细胞的抑制影响。(2)至 检查这些细胞中的双眼相互作用及其影响 这些相互作用对细胞的视觉反应特性产生了影响。(3) 揭示脑干网状结构在脑损伤中的作用 调节滞后和非滞后中继池的活动，以及 不同类型中间神经元在脑内的潜在参与 这种调制方式。(4)揭示细胞间的相互关系。 在AIMS 1中检查的形态和生理特性- 3.(5)揭示GABA能抑制在生物合成中的作用 滞后的LGN细胞的视觉反应特性。(6)至 确定滞后细胞和非滞后细胞的皮质连接 在区域17的第4层中，以及(7)可视化 这些传入神经接触的皮质细胞。标准 细胞外记录、视觉和电刺激方法 而细胞内染色将用于实现这些目标。 标准的药理学方法也将被用来实现 目标5. 所获得的结果将揭示对结构的重要见解 以及作为视觉信息处理基础的功能机制 在LGN和视皮层。

The long-range goal of this research program is to understand structure/function relationships that underlie information processing in the lateral geniculate nucleus (LGN) and visual cortex, and the interrelationships between the two brain regions. Experiments proposed here will address questions about the cell types which exist in the LGN, the mechanisms which affect their signal processing, and the cells' connections in visual cortex. The impetus for the experiments is the finding of a new type of X- relay cell (term lagged, or X cells) in the LGN A-laminae, whose functional and structural properties differ from other X-relay cells (termed non-lagged, or X - cells) and which appear to reflect intrageniculate inhibitory mechanisms related to cell structure. The present goal is to learn more about the physiological and morphological properties of these two geniculate X-cell groups and to identify the cortical cells which receive from them. The properties and projections of Y-cells, which probably also contain lagged and non-lagged groups, will be examined as well. Specific aims are as follows: (1) To characterize further the inhibitory influences on lagged and non-lagged LGN cells. (2) To examine binocular interactions in these cells and the influence of these interactions on the cells' visual response properties. (3) To reveal the role of the brainstem reticular formation in modulating the activity of lagged and non-lagged relay cells, and the potential involvement of different types of interneurons in this modulation. (4) To reveal the relationships between cells' morphologies and the physiological properties examined in aims 1- 3. (5) To reveal the role of GABAergic inhibition in generating the visual response properties of lagged LGN cells. (6) To determine the cortical connections of lagged and non-lagged cells in layer 4 of area 17, and (7) to visualize the morphologies of the cortical cells which these afferents contact. Standard extracellular recording, visual and electrical stimulation methods and intracellular staining will be used to accomplish these aims. Standard pharmacological methods also will be used to accomplish aim #5. The results obtained will reveal important insight into structural and functional mechanisms underlying visual information processing in LGN and visual cortex.