Visual responses in the brain of Limulus.
Visual responses in the brain of Limulus.
复制标题
鲎大脑中的视觉反应。
DOI：
10.1086/bblv187n2p260
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
BarlowJr,RB
中科院分区：
文献类型：
--
作者：
Passaglia,CL;Dodge,FA;BarlowJr,RB
马蹄蟹（Limulus polyphemus）的侧眼是动物界最容易理解的视觉结构之一。对侧眼的研究为我们提供了以下概念：适应量子突起以响应单个光子的吸收（1,2），侧抑制作为边缘增强的机制(3)，视网膜功能的昼夜节律调节(4)作为视觉引导行为的组成部分(5)。然而，我们对大脑如何处理视网膜输入以使动物看到所知相对较少。在这里，我们报告了来自层的第一个细胞内记录，这是大脑中视网膜信号的突触处理的第一级。玻璃微移液管（3.0 it4 KCl, 40-80 MQ），充入5%神经生物素1。O A4 KC1 (+ 0.5 nA, 5min)(8)垂直推进到手术暴露的脑原位。来自微电极的信号被送入桥式放大器，并用数字示波器进行监测。通过70 pm的光管将光刺激传递到视网膜上的单个受体单元（小眼），并通过光纤束将光刺激传递到眼睛的大片区域。我们经常刺穿在接收来自许多视神经纤维的突触输入和来自单个视神经纤维的动作电位的椎板中尚未确定的细胞区室。视网膜上单个小眼的照明通常会引起缓慢的去极化电位（0- 5 mV），并伴有单个动作电位（20-60 mV）序列，而整个视网膜的照明则会引起缓慢的超极化电位（5-15 mV）和减少的尖峰电位序列
The lateral eye of the horseshoe crab Limulus polyphemus is one of the best understood visual structures in the animal kingdom. Studies of the lateral eye have provided us with the concepts of adapting quanta1 bumps in response to the absorption of a single photon (1, 2), lateral inhibition as a mechanism of edge enhancement (3), and circadian modulation of retinal function (4) as a component of visually guided behaviors (5). We know relatively little, however, about how the brain processes retinal input for the animal to see (6, 7). Here we report on the first intracellular recordings from the lamina, the first level of synaptic processing of retinal signals in the brain. Glass micropipettes (3.0 it4 KCl, 40-80 MQ) filled with 5% Neurobiotin in 1. O A4 KC1 (+ 0.5 nA for 5 min)(8) were advanced vertically into the surgically exposed brain in situ. Signals from the microelectrodes were fed to a bridge amplifier and monitored with a digital oscilloscope. Light stimuli were delivered to individual receptor units (ommatidia) in the retina with a 70-pm light pipe and to large regions of the eye with a fiber optic bundle.We frequently impale as yet unidentified cellular compartments in the lamina that receive synaptic inputs from many optic nerve fibers and action potentials from a single optic nerve fiber. Illumination of a single ommatidium in the retina generally evokes slow depolarizing potentials (O-5 mV) in association with a single train of action potentials (20-60 mV) in the compartment, whereas illumination of the entire retina elicits slow hypet-polarizing potentials (5-15 mV) and a spike train of reduced