【摘要】 1.记录和分析了鲐鱼中脑视顶盖诱发电位(VETP)。波形基本特征同淡水鱼。2.在暗视条件下,光强和振幅间关系无简单规律可循,但峰潜伏期和光强关系满足关系式log(IT)=αlogⅠ+β,其中IT 为峰潜伏期;Ⅰ为刺激光强;α、β为常数。在明视时,此关系式在一定光强范围内依然成立。3.不同强度明适应时和暗适应过程中峰潜伏期的变化表明,决定峰潜伏期的主要因素是刺激光强,和网膜的适应状态关系不大。4.VETP 的暗适应曲线和ERG 的相同。5.VETP 暗视光谱敏感曲线和杆细胞视色素吸收光谱吻合得很好,提示在暗视条件下VETP 单一地反映了杆细胞的活动。在背景光强达4.07微瓦/平方厘米(角膜水平),短波段相对敏感度降低,长波段升高,但峰值并未向长波段位移。结合ERG 的结果推测,在更高背景光强时发生光谱敏感性的浦肯野位移是可能的。更多还原

【Abstract】 (1)The visually evoked tectum potential(VETP)of the Japanese mackerel wasrecorded.The waveforms were similar to those of freshwater fishes.(2)The relation between the amplitude of the VETP and light intensity ofstimulation does not follow a simple rule under scotopic conditions.The implicit timeof the various waves,on the other hand,bears a much more orderly relation tostimulation intensity which could be expressed by the equation log(IT)=β log Ⅰ+β,where IT is the implicit time,Ⅰ is the light intensity,α、β are constants.This relationalso holds true for a certain range of light intensities under photopic conditions.(3)The changes in the implicit time in the course of dark adaptation and atdifferent light adapted states suggest that the implicit time was mainly determined bythe intensity of stimulation and nearly independent of the state of adaptation.(4)The dark adaptation curve of the VETP bears good resemblance to that ofthe ERG.(5)The fact that the scotopic spectral sensitivity curve of the VETP fitted wellwith the absorption spectrum of the rod pigment suggests that the VETP solelyreflected the rod activity under scotopic conditions.When the intensity of backgroundlight reached 4.07μw/cm~2 on the cornea,the relative sensitivity decreased in theshort wavelength region and increased in the long wavelength region,although the displacement of the peak toward the longer wavelength did not occur.However,taking into account the results of the ERG,the occurence of the Purkinje shift mightbe expected at the higher background intensity.更多还原