COLOR AND CONNECTIVITY IN CONE PHOTORECEPTORS

视网膜上的图像转变为对 物理对象开始于光子能量的转换， 视杆和视锥光感受器中的电信号。 在离开之前， 将约1亿个光感受器的信号进行比较， 经过压缩、平均、分析和简化， 信息在视神经中流动。 这些神经节细胞神经纤维 携带的信息的形式，亮度，颜色和运动编码为 动作电位 光感受器曾经被认为是 独立的光传感器，就像照片中的单个颗粒一样， 电影，但这似乎不是真的。 事实上光感受器 包含视觉信息的第一层神经细胞， 也可能是第一个，也可能是第二个。 神经系统对视觉信息的分析水平。 有两个假设将与此赠款进行测试： 假设一：人类红色和绿色锥状色素的亚型是 每个视锥细胞随机表达一个基因。 对人类的直接检查 锥光谱敏感性将与分析的序列进行比较， 视色素蛋白质。 电子记录将给出精确的 光谱灵敏度函数的描述和并行的 表达的视色素蛋白的数量和种类将是 测定 具体问题是：是什么影响了光谱灵敏度 人体锥细胞是视觉色素的多个拷贝和变种 视觉色素基因的功能性表达基因， 手机？ 假设2：视锥细胞的光谱类别是不同的细胞类型， 形成耦合网络，排除其他光谱类别的锥。 将使用生理和解剖技术来评估尺寸 和视锥细胞感受野的光谱特性，这就需要 定量测定突触接触的强度， 相邻的圆锥体。 三个光谱类锥的存在， 人类提出了眼睛如何保持其完整性的问题。 三种颜色的“通道”，当信息池可能发生时 甚至在感光体层本身内。 以下问题将 （1）吃哺乳动物的锥体，与它们的 邻近的光感受器(2)是突触的相互作用 相邻的光感受器仅限于相同光谱类型的光感受器？（三） 人类和非人类哺乳动物兴奋的横向传播是什么 圆锥，和（4）是侧突的物理尺寸 相邻的光感受器之间的定量关系， 生理测量的细胞空间常数？

The transformation of an image on the retina into a perception of physical objects begins with the transduction of photon energy into electric signals in rod and cone photoreceptors. Prior to leaving the eye the signals of the -100 million photoreceptors are compared, compressed, averaged, analyzed and reduced into 1 million channels of information flowing in the optic nerve. These ganglion cell nerve fibers carry the information of form, brightness, color and motion encoded as action potentials. Photoreceptors were once thought to act as independent light sensors, like the individual grains of a photographic film, but this appears not to be true. In fact the photoreceptors, the first layer of nerve cells containing visual information, are in contact with one another and therefore may also be responsible for the first level of visual information analysis by the nervous system. There are two hypotheses that will be tested with this grant: Hypothesis I: The subtypes of human red and green cone pigments are expressed randomly one gene per cone cell. A direct examination of human cone spectral sensitives will be compared to the analyzed sequences of the visual pigments proteins. Electrical recording will give the precise descriptions of the spectral sensitivity functions and in parallel the number and variety of visual pigment proteins expressed will be determined. Specific questions are: What ate the spectral sensitivities of human cones? Are multiple copies and varieties of the visual pigment genes functionally expressed of visual pigment genes limited to one per cell? Hypothesis 2: Spectral classes of cones are distinct cell types, that form coupled networks which exclude other spectral classes of cones. Physiologic and anatomic techniques will be used to evaluate of the size and spectral characteristics of a cone's receptive field, this entails a quantitative determination of the strength of synaptic contact between neighboring cones. The presence of three spectral classes of cones in humans raises the issue of how the eye maintains the integrity of its three color "channels" when pooling of information is likely to occur even within the photoreceptor layer itself. The following questions will be approached: (1) Ate mammalian cones eclectically coupled to their neighboring photoreceptors? (2) Are synaptic interactions with neighboring photoreceptor limited to those of the same spectral type? (3) What is the lateral spread of excitation in human and non-human mammalian cones, and (4) are the physical dimensions of the lateral processes between neighboring photoreceptors quantitatively related to the physiologically measured space constant of the cell?