INPUT/OUTPUT RELATIONSHIPS IN VISUAL CORTEX

所提出的实验研究了 各种类型传入神经的终止模式， 神经元的树突状分支模式， 不同的目标 提出的两个具体问题是：1） 具有不同传出靶点的皮层神经元是否具有不同的 树枝状分支的模式 2)不同的来源 的传入终止相对于这些模式的 树枝化？ 本研究将在猫的后部进行 内侧外侧上外侧沟（PMLS），一个视觉区域， 不同来源的传入以及多个皮层和 皮层下传出靶点。 第一个问题是 使用轻轻固定的切片制备方法， 细胞内注射已经逆行的V层神经元， 从三个区域标记，已知在 视觉信息的处理，上级丘，脑桥， 和同侧纹状皮质。 的枝晶形貌 将比较投射到这些区域的神经元， 确定是否有不同的传入模式， 取样. 投射到其中两个部位的神经元，通过 也将逆行标记并在细胞内 以确定它们在形态上是否不同 只投射到其中一个部位的神经元。 的 第二个问题将通过制作单独的 顺行示踪剂离子导入三个区域 被认为是造成 PMLS神经元、后外侧/枕复合体、 板内核和同侧纹状体皮质。 顺行填充的轴突和它们的终扣将被绘制， 它们的分布与不同的树突状模式相比， 第五层投射神经元。 通过研究 在PMLS中输入到输出神经元，希望结果将 有助于理解这个区域在视觉上的作用 行为

The proposed experiments investigate the relationship between the pattern of termination of various types of afferents and the pattern of dendritic arborization of neurons that project to different targets. The two specific questions being posed are: 1) Do cortical neurons with different efferent targets have different patterns of dendritic arborization? 2) How do different sources of afferents terminate with respect to those patterns of arborization? This study will be carried-out in cat Posterior Medial Lateral Suprasylvian Sulcus (PMLS), a visual area with diverse sources of afferents as well as multiple cortical and subcortical efferent targets. The first question will be approached using a lightly fixed slice preparation to intracellularly inject layer V neurons that have been retrogradely labeled from three regions known to play different roles in the processing of visual information, the superior colliculus, pons, and ipsilateral striate cortex. The dendritic morphologies of neurons that project to these areas will be compared in order to determine if there are differences in patterns of afferent sampling. Neurons that project to two of these sites, via collaterals, will also be retrogradely labeled and intracellularly injected in order to determine if they are morphologically distinct from the neurons that project to only one of the two sites. The second question will be approached by making separate sets of iontophoretic injections of anterograde tracer into three regions thought to be responsible for the unique physiological properties of PMLS neurons, the lateral posterior/pulvinar complex, the intralaminar nuclei, and the ipsilateral striate cortex. Anterogradely filled axons and their boutons will be drawn and their distribution compared with the different dendritic patterns of layer V projecting neurons. By studying the relationship of input to output neurons in PMLS, it is hoped that the results will contribute to an understanding this region's role in visuomotor behavior.