Morrone M C, Burr D C, Fiorentini A
Istituto di Neurofisiologia del CNR, Pisa, Italy.
Vision Res. 1993 Dec;33(17):2535-52. doi: 10.1016/0042-6989(93)90133-h.
We have monitored the development of contrast sensitivity to equiluminant red-green chromatic patterns by monitoring visual evoked potentials (VEPs) in 13 infants. The results confirm our previous report [Morrone, Burr and Fiorentini, Proceedings of the Royal Society B, 242 (1990a)] that, before 7-8 weeks of age, there was no response to purely chromatic stimuli, while at the same age luminance stimuli of 20% contrast produced reliable responses. At all ages (even before the onset of a chromatic response) the colour mixture to yield equiluminance was similar to that of adults, suggesting that the relative proportion and efficacy of medium- and long-wave cones is similar for infants as for adults. For both luminance and chromatic stimuli, amplitude increased roughly linearly with log-contrast, so sensitivity thresholds could be predicted by linear extrapolation to the abscissa. Detailed contrast sensitivity curves were measured for four infants at various ages. The results show that luminance and chromatic contrast sensitivity develop independently at different rates, probably reflecting differential development of postreceptoral neural mechanisms.
我们通过监测13名婴儿的视觉诱发电位（VEP），来观察他们对等亮度红-绿颜色模式的对比敏感度发展情况。结果证实了我们之前的报告[莫罗内、伯尔和菲奥伦蒂尼，《皇家学会学报B》，242 (1990a)]，即在7至8周龄之前，婴儿对纯颜色刺激没有反应，而在相同年龄时，20%对比度的亮度刺激能产生可靠的反应。在所有年龄段（甚至在颜色反应开始之前），产生等亮度的颜色混合与成年人相似，这表明婴儿中、长波视锥细胞的相对比例和效能与成年人相似。对于亮度和颜色刺激，振幅大致随对数对比度呈线性增加，因此可以通过线性外推到横坐标来预测敏感度阈值。我们测量了4名不同年龄婴儿的详细对比敏感度曲线。结果表明，亮度和颜色对比敏感度以不同速率独立发展，这可能反映了感受器后神经机制的不同发展情况。
