Cognitive response profile of the human fusiform face area as determined by MEG
Cognitive response profile of the human fusiform face area as determined by MEG
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DOI：
10.1093/cercor/10.1.69
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发表时间：
2000-01-01
期刊：
影响因子：
3.7
通讯作者：
Hari, R
中科院分区：
文献类型：
--
作者：
Halgren, E;Raij, T;Hari, R
梭状回内或附近的激活被估计为面部和控制刺激。激活在165毫秒时达到峰值，并且对数字化人脸照片的激活最强，无论它们是以彩色还是灰度呈现的，这表明人脸特定区域和颜色特定区域在功能上是分开的。示意图比面部照片引起的激活少30%。打乱面部特征的位置会使两个半球的反应减少25%，这表明在这种延迟中，构型处理与分析处理并没有侧向化。与人脸相比，动物面孔引起的活动减少了50%，而普通物体、动物身体或感官控制引起的活动减少了80%。当无意义的对照图像包含表面和阴影时，引起的（小）反应更强，这表明梭状回可能使用这些特征来构建其面部特异性反应。假定梭状回激活与刺激重复、性别或情绪表达无显著相关。枕部中线源早在110 ms时就能显著区分人脸和对照图像，但对感官品质更为敏感。这一来源显著地将快乐和悲伤的脸与中性表情区分开来。我们得出结论，梭状回可能在165 ms时选择性地对面部进行编码，将感觉输入转化为进一步的处理。
Activation in or near the fusiform gyrus was estimated to faces and control stimuli. Activation peaked at 165 ms and was strongest to digitized photographs of human faces, regardless of whether they were presented in color or grayscale, suggesting that face- and color-specific areas are functionally separate. Schematic sketches evoked similar to 30% less activation than did face photographs. Scrambling the locations of facial features reduced the response by similar to 25% in either hemisphere, suggesting that configurational versus analytic processing is not lateralized at this latency. Animal faces evoked similar to 50% less activity, and common objects, animal bodies or sensory controls evoked similar to 80% less activity than human faces. The (small) responses evoked by meaningless control images were stronger when they included surfaces and shading, suggesting that the fusiform gyrus may use these features in constructing its face-specific response. Putative fusiform activation was not significantly related to stimulus repetition, gender or emotional expression. A midline occipital source significantly distinguished between faces and control images as early as 110 ms, but was more sensitive to sensory qualities. This source significantly distinguished happy and sad faces from those with neutral expressions. We conclude that the fusiform gyrus may selectively encode faces at 165 ms, transforming sensory input for further processing.