Department of Neuroscience, Erasmus MC, Rotterdam, The Netherlands.
Exp Brain Res. 2008 May;187(2):219-28. doi: 10.1007/s00221-008-1296-x. Epub 2008 Feb 7.
Neurons in different cortical visual areas respond to different visual attributes with different latencies. How does this affect the on-line control of our actions? We studied hand movements directed toward targets that could be distinguished from other objects by luminance, size, orientation, color, shape or texture. In some trials, the target changed places with one of the other objects at the onset of the hand's movement. We determined the latency for correcting the movement of the hand in the direction of the new target location. We show that subjects can correct their movements at short latency for all attributes, but that responses for the attributes color, form and texture (that are relevant for recognizing the object) are 50 ms slower than for the attributes luminance, orientation and size. This dichotomy corresponds to both to the distinction between magno-cellular and parvo-cellular pathways and to a dorsal-ventral distinction. The latency also differed systematically between subjects, independent of their reaction time.
不同皮质视觉区域的神经元以不同的潜伏期对不同的视觉属性做出反应。这如何影响我们行为的在线控制?我们研究了指向目标的手部运动,这些目标可以通过亮度、大小、方向、颜色、形状或纹理与其他物体区分开来。在一些试验中,在手部运动开始时,目标与其他物体之一交换位置。我们确定了校正手部向新目标位置移动的潜伏期。我们表明,对于所有属性,受试者都可以以短潜伏期校正他们的运动,但对于颜色、形状和纹理(对于识别物体很重要)的属性的反应比亮度、方向和大小的属性慢 50 毫秒。这种二分法既对应于大细胞和小细胞通路之间的区别,也对应于背腹部分化。潜伏期也在不同的受试者之间系统地差异,与他们的反应时间无关。