Abstract：
There has been much debate on whether color categories affect how we perceive color. Recent theories have put emphasis on the role of top-down influence on color perception that the original continuous color space in the visual cortex may be transformed into categorical encoding due to top-down modulation. To test the influence of color categories on color perception, we adopted an RSVP paradigm, where color stimuli were presented at a fast speed of 100 ms per stimulus and were forward and backward masked by the preceding and following stimuli. Moreover, no explicit color naming or categorization was required. In theory, backward masking with such a short interval in a passive viewing task should constrain top-down influence from higher-level brain areas. To measure any potentially subtle differences in brain response elicited by different color categories, we embedded a sensitive frequency-tagging-based EEG paradigm within the RSVP stimuli stream where the oddball color stimuli were encoded with a different frequency from the base color stimuli. We showed that EEG responses to cross-category oddball colors at the frequency where the oddball stimuli were presented was significantly larger than the responses to within-category oddball colors. Our study suggested that the visual cortex can automatically and implicitly encode color categories when color stimuli are presented rapidly.
摘要：
关于颜色类别是否会影响我们对颜色的感知，一直存在很多争论。最近的理论强调了自上而下的影响对颜色感知的作用，即由于自上而下的调制，视觉皮层中原始的连续颜色空间可能会转换为分类编码。为了测试颜色类别对颜色感知的影响，我们采用了RSVP范式，其中颜色刺激以每次刺激100ms的快速速度呈现，并被前后刺激所掩盖。此外，不需要明确的颜色命名或分类.理论上,在被动观看任务中以如此短的间隔进行反向掩蔽应该会限制来自较高级别的大脑区域的自上而下的影响。为了测量不同颜色类别引起的大脑反应的任何潜在细微差异，我们在RSVP刺激流中嵌入了基于频率标记的敏感EEG范例,其中oddball颜色刺激以与基础颜色刺激不同的频率进行编码。我们表明，在出现怪球刺激的频率下，EEG对跨类别怪球颜色的反应明显大于对类别内怪球颜色的反应。我们的研究表明，当颜色刺激快速呈现时，视觉皮层可以自动且隐式地编码颜色类别。
