Schmidt Thomas
Institute of Psychology, University of Göttingen, Germany.
Psychol Sci. 2002 Mar;13(2):112-8. doi: 10.1111/1467-9280.00421.
Current theories of dual visual systems suggest that color is processed in a ventral cortical stream that eventually gives rise to visual awareness but is only indirectly involved in visuomotor control mediated by the dorsal stream. If the dorsal stream is indeed less sensitive to color than the ventral stream, color stimuli blocked from awareness by visual masking should also be blocked from guiding fast motor responses. In this study, pointing movements to one of two isoluminant color targets were preceded by consistent or inconsistent color primes. Trajectories were strongly affected by priming, with kinematics implying a continuous flow of color information into executive brain areas while the finger was already moving. Motor effects were more sensitive to color of the primes than were deliberate attempts to identify the primes in forced-choice tasks based on visual awareness. Priming was observed even when masking was complete.
当前的双重视觉系统理论表明，颜色在腹侧皮质通路中进行处理，最终产生视觉意识，但仅间接参与由背侧通路介导的视觉运动控制。如果背侧通路确实比腹侧通路对颜色的敏感度更低，那么被视觉掩蔽阻断意识的颜色刺激也应该被阻断以引导快速运动反应。在本研究中，指向两个等亮度颜色目标之一的指向运动之前会出现一致或不一致的颜色启动刺激。运动轨迹受到启动刺激的强烈影响，运动学表明当手指已经在移动时，颜色信息持续流入执行脑区。与基于视觉意识在强制选择任务中刻意识别启动刺激的尝试相比，运动效应对启动刺激的颜色更敏感。即使掩蔽完全，也观察到了启动效应。
