Gibbs M A, Northmore D P
Department of Biology, University of Delaware, Newark, USA.
Vis Neurosci. 1998 Sep-Oct;15(5):859-65. doi: 10.1017/s0952523898155086.
We measured the photopic spectral sensitivity of multiunit activity in the torus longitudinalis and optic tectum of goldfish. Since negative contrast stimuli are most effective for exciting torus longitudinalis, spiking activity was evoked by the shadow of a disc moving through a monochromatic light beam projected upon a screen. The amount of activity evoked in torus longitudinalis generally increased with the monochromatic stimulus radiance at the same rate for all wavelengths, indicating a univariant response. Spiking activity in tectum, however, increased at different rates across the spectrum, indicating color-dependent responses. The action spectra for torus longitudinalis were all similar and relatively flat as expected of a homogeneous, broad-band luminance processing system, and about 1 log unit more sensitive than the tectal action spectra. The latter generally displayed sharp peaks and dips in sensitivity indicative of opponent processing.
我们测量了金鱼半环隆凸和视顶盖中多单位活动的明视觉光谱敏感性。由于负对比度刺激对激发半环隆凸最为有效，通过在投射到屏幕上的单色光束中移动圆盘的阴影来诱发放电活动。在半环隆凸中诱发的活动量通常随单色刺激辐射率以相同速率增加，且对所有波长均如此，表明是单变量反应。然而，视顶盖中的放电活动在整个光谱范围内以不同速率增加，表明存在颜色依赖性反应。半环隆凸的作用光谱都相似且相对平坦，这正如均匀的宽带亮度处理系统所预期的那样，并且比视顶盖的作用光谱敏感约1个对数单位。后者通常在敏感性上呈现出尖锐的峰值和谷值，表明存在拮抗加工。
