Spatio-temporal receptive field organizaion of tectal neurons of the frog and identification of responsible input fibers

视觉刺激器使用幻灯片投影仪和带有2个AXS程序控制器的x-y工作台。这种刺激器使我们能够在屏幕上的离散网格位置上给出视觉图案或做出连续的运动图案。使用这种刺激器，我们记录了青蛙顶盖神经元的细胞内反应。视网膜纤维有4类(R1、R2、R3和R4)，它们直接投射到视盖。当在网格点给予开关刺激时，可以区分R3和R4的贡献(R1和R2没有反应)。通过测量不同时间点的反应幅度，获得兴奋和抑制的空间分布。为了克服细胞内记录的困难，建立了体内全细胞记录技术。应用这种方法，我们同时记录了顶盖神经元的突触电位和单根视神经纤维的冲动。应用脉冲触发相关法，可以识别出由R1/R2、R3和R4诱发的EPSP。我们测量了EPSPS的起搏时间和波幅，确定了一元性EPSPS。可定义潜伏期、单突触和双突触EPSP的测量。

Visual stimulator was made using a slide projector and an x-y stage with 2 axs program controler. This stimulator enabled us to give visual patterns on discrete grid positions on the screen or to make continuous moving patterns.Using this stimulator, intracelluar responses of tectal neurons of the frog were recorded intracellulary. There are 4 classes of retinal fibers (R1, R2, R3 and R4) and they directly projet to optic tecum. When on-off stimulation was given on grid points, it was possible to distinguish contribution of R3 from R4 (R1 and R2 produces no response). By measuring the amplitude of the responses at different time, spatial distribution of excitation and inhibition was obtained.In order to overcome the difficulty of intracellular recording, in vivo whole cell recording technique was established. Applying this method, synaptic potentials from tectal neurons was recorded simultaneously with impulses from a single optic nerve fiber. Application of pulse-triggered correlation method, EPSPs elicited by R1/R2, R3 and R4 could be identified. We measured rize time and amplitude of EPSPs, and identified unitary EPSPs. Mesurement of latency, monosynaptice and disynaptic EPSP could be difined.