VISION AND INTRARETINAL POTENTIALS

这项研究旨在加深对神经生理学的理解 视网膜上的。将进行实验来研究基本问题 对比视觉，颜色编码和暗适应。这件事会做到的 通过分析双极细胞、无长突细胞、 水平细胞、视锥细胞和神经节细胞。这项研究将是 在为细胞内提供独特机会的动物身上进行 正在录音。许多实验都是与心理物理工作平行的，所以 相比之下，结果可能导致临床疾病的新模型 感知和黑暗适应。 亮度对比度的信号将在泥巴小狗(Necturus)中进行研究 斑疹)。将获得数据来分析这一事件的意义 双极细胞的双重组织--“对比”的性质和基础 无长突细胞中的“整流”，信号的相互关系 由负向和正向对比产生的，以及 谷氨酸激动剂L 2-氨基-4-磷酸丁酸酯(L-AP4) 对比信号。 第二个项目试图澄清色彩型水平的作用 视网膜功能的细胞(C细胞)。主要方法将包括 在C细胞中注入电流，并在神经节细胞中记录该效应。 其他关键要素包括使用淡水鱼(弓鳍，Amia Calva)，对于这类工作具有特殊的优势，新技术 分离神经节细胞的脉冲放电和新的实验 范式(L光谱和红/绿交流)。 第三个项目将研究视锥感光细胞的暗适应。 特殊功能包括使用超融合切片制备 海龟眼罩和氦-霓虹激光产生强烈的适应 灯光。覆盖近8个对数单位的暗适应曲线将 获得了比脊椎动物圆锥体中已研究的大约5个对数单位。 其他实验将分析膜电位、时间分辨率、 电压敏感机制与黑暗中的色素再生 适应。

This research seeks to advance out understanding of the neurophysiology of the retina. Experiments will be performed to study fundamental issues in Contrast Vision, Color Coding and Dark Adaptation. This will be done by analyzing the light-evoked responses of bipolar cells, amacrine cells, horizontal cells, cones, and ganglion cells. The research will be performed on animals which offer unique opportunities for intracellular recording. Many of the experiments parallel psychophysical work so the results could lead to new models for clinical disorders in contrast perception and dark adaptation. Signals for luminance contrast will be studied in the mudpuppy (Necturus maculosus). Data will be obtained to analyze the significance of the dual organization of bipolar cells, the properties and bases of "contrast rectification" in amacrine cells, the interrelationship of signals generated by negative and positive contrast, and the effect of the glutamate agonist, L 2-amino-4 phosphono-butyrate (APB, L-AP4), on contrast signals. The second project seeks to clarify the role of chromatic-type horizontal cells (C cells) in retinal function. The main approach will consist of injecting current in C cells and recording the effect in ganglion cells. Other key elements include the use of a freshwater fish (the bowfin, Amia calva) which has special advantages for such work, new techniques for isolating the impulse discharge of ganglion cells, and new experimental paradigms (the L spectrum and red/green exchange). The third project will study dark adaptation in cone photoreceptor cells. Special features include the use of a superfused slice preparation of the turtle eyecup and a helium-neon laser to generate intense adapting lights. Dark adaptation curves covering nearly 8 log units will be obtained, some 5 log units greater than yet studied in vertebrate cones. Other experiments will analyze membrane potential, temporal resolution, voltage-sensitive mechanisms and pigment regeneration during dark adaptation.