Santos Isabel M, Iglesias Jaime, Olivares Ela I, Young Andrew W
Universidade de Aveiro, Departamento de Ciências da Educação, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Neuropsychologia. 2008 Apr;46(5):1468-79. doi: 10.1016/j.neuropsychologia.2007.12.024. Epub 2008 Jan 5.
Event-related potentials (ERPs) were used to investigate the role of attention on the processing of facial expressions of fear and disgust. Stimuli consisted of overlapping pictures of a face and a house. Participants had to monitor repetitions of faces or houses, in separate blocks of trials, so that object-based attention was manipulated while spatial attention was kept constant. Faces varied in expression and could be either fearful or neutral (in the fear condition) or disgusted or neutral (in the disgust condition). When attending to faces, participants were required to signal repetitions of the same person, with the facial expressions being completely irrelevant to the task. Different effects of selective attention and different patterns of brain activity were observed for faces with fear and disgust expressions. Results indicated that the perception of fear from faces is gated by selective attention at early latencies, whereas a sustained positivity for fearful faces compared to neutral faces emerged around 160ms at central-parietal sites, independent of selective attention. In the case of disgust, ERP differences began only around 160ms after stimulus onset, and only after 480ms was the perception of disgust modulated by attention allocation. Results are interpreted in terms of different neural mechanisms for the perception of fear and disgust and related to the functional significance of these two emotions for the survival of the organism.
事件相关电位（ERP）被用于研究注意力在恐惧和厌恶面部表情加工中的作用。刺激物由脸和房子的重叠图片组成。参与者必须在不同的试验块中监测脸或房子的重复出现，以便在保持空间注意力恒定的同时操纵基于物体的注意力。脸的表情各异，在恐惧条件下可以是恐惧的或中性的，在厌恶条件下可以是厌恶的或中性的。当关注脸时，要求参与者对同一个人的重复出现发出信号，面部表情与任务完全无关。对于带有恐惧和厌恶表情的脸，观察到了选择性注意的不同效应和不同的大脑活动模式。结果表明，在早期潜伏期，对面部恐惧的感知受到选择性注意的调节，而在中央顶叶部位，与中性脸相比，恐惧脸在约160毫秒左右出现持续的正电位，与选择性注意无关。在厌恶的情况下，ERP差异仅在刺激开始后约160毫秒才开始出现，并且只有在480毫秒后，厌恶的感知才受到注意力分配的调节。研究结果从恐惧和厌恶感知的不同神经机制角度进行了解释，并与这两种情绪对生物体生存的功能意义相关联。
