Functional MRI Research Center, Columbia University, Neurological Institute B41, 710 W. 168th Street, New York, NY 10032, USA.
Neuropsychologia. 2011 Feb;49(3):564-73. doi: 10.1016/j.neuropsychologia.2010.12.019. Epub 2010 Dec 17.
The self-face is thought to be an especially salient stimulus. Behavioral evidence suggests that self-face processing advantage is associated with enhanced processing of temporally adjacent subliminal stimuli. However, the neural basis of this self-related processing modulation has not been investigated. We studied self-face induced signal amplification through masked priming and repetition suppression (fMRI adaptation). Subjects performed a gender-categorization task on self- and non-self target faces preceded by subliminal (17 ms) prime faces. The relationship between prime and target was varied between task-incongruent (when prime and target belonged to a different gender) and task-congruent (when prime and target belonged to the same gender) pairs. We found that, in the presence of the visible self-face (but not of other non-self faces), a bilateral fronto-parietal network exhibited repetition suppression to subliminal prime faces belonging to the same gender (task-congruent) as the target, consistent with the notion that, in the presence of the self-face, subliminal stimuli access high-level processing systems. These results are in agreement with the notion of self-specific top-down amplification of subliminal task-relevant information, and suggest that the self-face, through its high salience, is particularly efficacious in focusing attention.
自我面孔被认为是一种特别突出的刺激。行为证据表明,自我面孔处理优势与对时间上相邻的阈下刺激的增强处理有关。然而,这种与自我相关的处理调节的神经基础尚未被研究过。我们通过掩蔽启动和重复抑制(fMRI 适应)研究了自我面孔引起的信号放大。受试者在阈下(17 毫秒)的启动面孔之前对自我和非自我目标面孔执行性别分类任务。启动和目标之间的关系在任务不一致(当启动和目标属于不同性别时)和任务一致(当启动和目标属于同一性别时)之间变化。我们发现,在可见的自我面孔存在的情况下(而不是其他非自我面孔),双侧额顶叶网络对属于与目标相同性别的阈下启动面孔表现出重复抑制(任务一致),这与在自我面孔存在的情况下,阈下刺激可以进入高级处理系统的观点一致。这些结果与阈下与任务相关的信息的自我特定的自上而下放大的观点一致,并表明自我面孔通过其高显著性,特别有效地集中注意力。