Vorobyev M, Brandt R, Peitsch D, Laughlin S B, Menzel R
Institut für Neurobiologie, Freie Universität Berlin, Königin-Luise-Str. 28-30, 14195, Berlin, Germany.
Vision Res. 2001 Mar;41(5):639-53. doi: 10.1016/s0042-6989(00)00288-1.
Photoreceptor noise sets an absolute limit for the accuracy of colour discrimination. We compared colour thresholds in the honeybee (Apis mellifera) with this limit. Bees were trained to discriminate an achromatic stimulus from monochromatic lights of various wavelengths as a function of their intensity. Signal-to-noise ratios were measured by intracellular recordings in the three spectral types of photoreceptor cells. To model thresholds we assumed that discrimination was mediated by opponent mechanisms whose performance was limited by receptor noise. Most of the behavioural thresholds were close to those predicted from receptor signal-to-noise ratios, suggesting that colour discrimination in honeybees is affected by photoreceptor noise. Some of the thresholds were lower than this theoretical limit, which indicates summation of photoreceptor cell signals.
光感受器噪声为颜色辨别精度设定了绝对限制。我们将蜜蜂（西方蜜蜂）的颜色阈值与该限制进行了比较。训练蜜蜂根据不同波长单色光的强度来辨别无彩色刺激。通过对三种光谱类型的光感受器细胞进行细胞内记录来测量信噪比。为了模拟阈值，我们假设辨别是由拮抗机制介导的，其性能受受体噪声限制。大多数行为阈值接近根据受体信噪比预测的值，这表明蜜蜂的颜色辨别受光感受器噪声影响。一些阈值低于该理论极限，这表明存在光感受器细胞信号的总和。
