Schiller P H, Logothetis N K, Charles E R
Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge 02139.
Neuropsychologia. 1991;29(6):433-41. doi: 10.1016/0028-3932(91)90003-q.
It has been proposed that the functions of the two major parallel channels of the primate visual system, the color-opponent and the broad-band, can be determined in psychophysical experiments by eliminating luminance but maintaining chrominance information (isoluminance), since under such conditions the broad-band channel is believed to be silenced. To test this proposition we examined the visual functions of monkeys after blocking either of these channels and we also assessed the responses of neurons to isoluminant stimuli in the lateral geniculate nucleus. We show that color, texture, stereopsis and pattern perception in the absence of the color-opponent channel, and flicker and motion perception in the absence of the broad-band channel are compromised. Yet isoluminance functions for stereopsis and texture in the absence of the broad-band channel and for motion in the absence of the color-opponent channel are indistinguishable from normal. Our recordings show that the neuronal responses of the broad-band cells for isoluminant exchange of red and green lights are reduced but not eliminated and that the color-opponent cells also become similarly less responsive under these conditions. We conclude that perceptual losses at isoluminance are not specific for either channel.
有人提出，在灵长类动物视觉系统的两个主要并行通道中，即颜色拮抗通道和宽带通道，其功能可以在心理物理学实验中通过消除亮度但保留色度信息（等亮度）来确定，因为在这种条件下，宽带通道被认为会沉默。为了验证这一观点，我们在阻断这两个通道中的任意一个后，研究了猴子的视觉功能，并且我们还评估了外侧膝状核中神经元对等亮度刺激的反应。我们发现，在没有颜色拮抗通道的情况下，颜色、纹理、立体视觉和图案感知会受损，而在没有宽带通道的情况下，闪烁和运动感知会受损。然而，在没有宽带通道的情况下，立体视觉和纹理的等亮度功能以及在没有颜色拮抗通道的情况下运动的等亮度功能与正常情况并无差异。我们的记录表明，对于红光和绿光的等亮度交换，宽带细胞的神经元反应会降低但不会消除，并且在这些条件下，颜色拮抗细胞的反应也同样会减弱。我们得出结论，等亮度条件下的感知损失并非特定于任何一个通道。
