Correlation Among Retinal Directionally Selective Cells

描述(摘自申请人的摘要)： 视觉神经科学中的一个中心问题是绑定问题。这是怎么回事 大脑知道它必须将神经元的反应与微小的视觉联系在一起 窗口，以获得大型物体的连贯图片？中国的一个长期目标是 拟议的研究是为了阐明视觉背后的视网膜机制 有约束力的。关于这些机制的三个假说涉及 神经节细胞，以及常见的胆碱能、谷氨酸和GABA能突触。 四个具体目标将在方向性上检验这些假设 乌龟和兔子的神经节细胞，因为有证据表明长轮廓结合 存在以下单元格： 1)这个目标将测试毫秒相关性是否可以编码长的、移动的 通过同时记录来自相邻方向敏感的等高线 细胞与电生理技术。 2)这里的实验将使用同步电生理记录 和药理学来测试GABA，乙酰胆碱，谷氨酸和缝隙连接 视网膜相关性假说。 3)特定目标3将研究长期关联是否发生在 用LIVE定位定向选择细胞群体 钙离子荧光。 4)最后，最后一个目标将检验胆碱能假说的预测 通过测量运动适应后的乙酰胆碱释放来进行相关性 高效液相色谱分离。 结合的研究可能具有重要的健康意义。精神分裂症 例如，患者无法在依赖远程任务的情况下检测轮廓 方位信号的空间相互作用。并整合了 弱视患者的空间方位信息受损。视网膜结合 缺陷可能会导致其中一些综合问题，但即使不是， 视网膜的策略和机制可能有助于阐明其他领域的机制 大脑的一部分。

DESCRIPTION (From the Applicant's Abstract): A central problem in visual neuroscience is the binding problem. How does the brain know that it has to bind the responses of neurons with small visual windows to obtain coherent pictures of large objects? One long-term goal of the proposed research is to elucidate the retinal mechanisms underlying visual binding. Three hypotheses for these mechanisms involve gap junctions between ganglion cells, and common cholinergic, glutamatergic, and GABAergic synapses. Four specific aims will test these hypotheses in directionally selective ganglion cells of turtles and rabbits, since evidence of long-contour binding exists for these cells: 1)This aim will test whether millisecond correlation could code long, moving contours by recording simultaneously from neighbor directionally sensitive cells with electrophysiological techniques. 2)The experiments here will use simultaneous electrophysiological recordings and pharmacology to test the GABA, acetylcholine, glutamate, and gap-junction hypotheses of retinal correlation. 3)Specific aim 3 will study whether long-range correlation takes place by mapping the population of directionally selective cells with live Ca2+fluorescence. 4)Finally, the last aim will test a prediction of the cholinergic hypothesis for correlation by measuring acetylcholine release following motion adaptation with high performance liquid chromatography. The study of binding may have important health relevance. Schizophrenia patients, for instance, cannot detect contours in tasks relying on long-range spatial interactions of orientational signals. And the integration of orientation information across space is impaired in amblyopia. Retinal binding defects may contribute to some of these integrative problems, but even if not, retinal strategies and mechanisms may shed light on mechanisms in other areas of the brain.