Boon Mei Ying, Suttle Catherine M, Dain Stephen J
School of Optometry and Vision Science, University of New South Wales, Sydney, NSW 2052, Australia.
Vision Res. 2007 Jul;47(16):2124-33. doi: 10.1016/j.visres.2007.04.019. Epub 2007 Jun 12.
It has been found that humans are able to distinguish colours without luminance cues by about 2-4 months of age and that sensitivity to colour difference develops during childhood, reaching a peak around adolescence. This prolonged period of maturation is reflected by improvements in psychophysical threshold measures and by the VEP characteristics of morphology, latency and amplitude. An intra-individual comparison of VEP and psychophysical responses to isoluminant colour stimuli has not been made in children, however, and this was the aim of the present study. VEPs were recorded from 49 subjects, children (age range: 4.8-12.6 years) and adults (age range: 25.7-33.2 years). Psychophysical and VEP thresholds were both measured in 40 of those subjects. Nominally isoluminant chromatic (L-M) sinewave gratings were presented in onset-offset mode and identical stimuli were used for psychophysical and VEP recordings to allow comparison. In agreement with previous reports, morphology of the transient VEP in response to this stimulus differed considerably between children and adults. There was a significant difference between psychophysical and VEP thresholds in children, but not in adults. Our findings support and expand on previous work on maturation of the L-M chromatic pathway and indicate a larger discrepancy between VEP and psychophysical chromatic thresholds in children than in adults.
研究发现，人类在大约2至4个月大时就能在没有亮度线索的情况下辨别颜色，并且对色差的敏感度在儿童期不断发展，在青春期左右达到峰值。这种较长的成熟阶段体现在心理物理学阈值测量的改善以及视觉诱发电位（VEP）在形态、潜伏期和波幅方面的特征变化上。然而，尚未对儿童针对等亮度颜色刺激的VEP和心理物理学反应进行个体内比较，而这正是本研究的目的。对49名受试者（儿童年龄范围：4.8至12.6岁，成人年龄范围：25.7至33.2岁）记录了VEP。其中40名受试者同时测量了心理物理学阈值和VEP阈值。以开-关模式呈现名义上的等亮度彩色（L-M）正弦波光栅，并将相同的刺激用于心理物理学和VEP记录以便进行比较。与先前的报告一致，儿童和成人对该刺激的瞬态VEP形态存在显著差异。儿童的心理物理学阈值和VEP阈值之间存在显著差异，而成人则没有。我们的研究结果支持并扩展了先前关于L-M色觉通路成熟的研究工作，表明儿童的VEP和心理物理学颜色阈值之间的差异比成人更大。
