Coelho Carlos M, Cloete Steven, Wallis Guy
Queensland Brain Institute and School of Human Movement Studies, University of Queensland, Australia.
J Vis. 2010 Jan 13;10(1):7.1-14. doi: 10.1167/10.1.7.
A common theme running through much of the visual recognition literature is that faces are special. Many studies now describe evidence for the idea that faces are processed in a dedicated center in cortex. Studies have also argued for the presence of evolutionarily expedient pathways dedicated to the processing of certain facial expressions. Evidence for this proposal comes largely from visual search tasks which have established that threatening expressions are more rapidly detected than other expressions: the 'face-in-the-crowd effect'. One open criticism of this effect is that it may be due to low-level visual artifacts, rather than biological preparedness. One attempt at controlling low-level differences has been to use schematic line-drawing versions of faces. This study aimed to discover if there might be alternative issues with schematic stimuli. The first study replicated the face-in-the-crowd threat advantage for schematic faces, but also measured a comparable effect using stimuli comprised of obliquely oriented lines. Similar results were achieved with these stimuli rotated, which had the effect of removing any residual resemblance to a face. The results suggest that low-level features probably underlie the face-in-the-crowd effect described for schematic face images, thereby undermining evidence for a search advantage for specific facial expressions.
贯穿众多视觉识别文献的一个共同主题是，面部具有特殊性。现在许多研究都描述了这样一种观点的证据，即面部在大脑皮层的一个专门区域进行处理。研究还主张存在专门用于处理某些面部表情的进化上便利的通路。这一观点的证据主要来自视觉搜索任务，这些任务证实，与其他表情相比，威胁性表情能被更快地检测到：即“人群中的脸效应”。对这一效应的一个公开批评是，它可能是由于低层次的视觉假象，而非生物适应性。控制低层次差异的一种尝试是使用面部的示意性线条图版本。本研究旨在探究示意性刺激是否可能存在其他问题。第一项研究重现了示意性面部的“人群中的脸威胁优势”，但也使用由倾斜线条组成的刺激测量了类似的效应。这些刺激旋转后也得到了类似结果，这消除了与面部的任何残余相似性。结果表明，低层次特征可能是示意性面部图像所描述的“人群中的脸效应”的基础，从而削弱了特定面部表情具有搜索优势的证据。
