Ito Tiffany A, Urland Geoffrey R
Department of Psychology, University of Colorado, 345 UCB, Boulder, CO 80309-0345, USA.
Cogn Affect Behav Neurosci. 2005 Mar;5(1):21-36. doi: 10.3758/cabn.5.1.21.
In two experiments, event-related potentials were used to examine the effects of attentional focus on the processing of race and gender cues from faces. When faces were still the focal stimuli, the processing of the faces at a level deeper than the social category by requiring a personality judgment resulted in early attention to race and gender, with race effects as early as 120 msec. This time course corresponds closely to those in past studies in which participants explicitly attended to target race and gender (Ito & Urland, 2003). However, a similar processing goal, coupled with a more complex stimulus array, delayed social category effects until 190 msec, in accord with the effects of complexity on visual attention. In addition, the N170 typically linked with structural face encoding was modulated by target race, but not by gender, when faces were perceived in a homogenous context consisting only of faces. This suggests that when basic-level distinctions between faces and nonfaces are irrelevant, the mechanism previously associated only with structural encoding can also be sensitive to features used to differentiate among faces.
在两项实验中，事件相关电位被用于检验注意力焦点对处理来自面部的种族和性别线索的影响。当面部仍然是焦点刺激时，通过要求进行个性判断在比社会类别更深的层面上对面部进行处理，会导致对种族和性别的早期关注，种族效应最早在120毫秒出现。这个时间进程与过去研究中参与者明确关注目标种族和性别的研究结果非常吻合（伊藤和厄兰，2003年）。然而，类似的处理目标，再加上更复杂的刺激阵列，将社会类别效应延迟到了190毫秒，这与复杂性对视觉注意力的影响一致。此外，当面部在仅由面部组成的同质背景中被感知时，通常与面部结构编码相关的N170受目标种族调制，但不受性别调制。这表明当面部与非面部之间的基本层面区分不相关时，先前仅与结构编码相关的机制也可能对用于区分面部的特征敏感。
