Fisher Katie, Towler John, Eimer Martin
Department of Psychological Sciences, Birkbeck, University of London, UK.
Department of Psychological Sciences, Birkbeck, University of London, UK.
Cortex. 2017 Apr;89:11-27. doi: 10.1016/j.cortex.2017.01.003. Epub 2017 Jan 11.
Individuals with developmental prosopagnosia (DP) have severe face recognition deficits, but the mechanisms that are responsible for these deficits have not yet been fully identified. We assessed whether the activation of visual working memory for individual faces is selectively impaired in DP. Twelve DPs and twelve age-matched control participants were tested in a task where they reported whether successively presented faces showed the same or two different individuals, and another task where they judged whether the faces showed the same or different facial expressions. Repetitions versus changes of the other currently irrelevant attribute were varied independently. DPs showed impaired performance in the identity task, but performed at the same level as controls in the expression task. An electrophysiological marker for the activation of visual face memory by identity matches (N250r component) was strongly attenuated in the DP group, and the size of this attenuation was correlated with poor performance in a standardized face recognition test. Results demonstrate an identity-specific deficit of visual face memory in DPs. Their reduced sensitivity to identity matches in the presence of other image changes could result from earlier deficits in the perceptual extraction of image-invariant visual identity cues from face images.
患有发展性面孔失认症（DP）的个体存在严重的面部识别缺陷，但导致这些缺陷的机制尚未完全明确。我们评估了DP患者对个体面孔的视觉工作记忆激活是否存在选择性受损。12名DP患者和12名年龄匹配的对照参与者接受了测试，一项任务是让他们报告相继呈现的面孔是否为同一个人或两个不同的人，另一项任务是让他们判断面孔的表情是否相同或不同。其他当前无关属性的重复与变化是独立变化的。DP患者在身份任务中的表现受损，但在表情任务中的表现与对照组相当。身份匹配激活视觉面孔记忆的电生理标记（N250r成分）在DP组中显著减弱，且这种减弱的程度与标准化面部识别测试中的较差表现相关。结果表明DP患者存在特定于身份的视觉面孔记忆缺陷。在存在其他图像变化的情况下，他们对身份匹配的敏感性降低可能源于早期在从面部图像中感知提取图像不变视觉身份线索方面的缺陷。
