Farran Emily K, Mares Inês, Papasavva Michael, Smith Fraser W, Ewing Louise, Smith Marie L
School of Psychology, University of Surrey, UK.
Department of Psychological Sciences, Birkbeck College, University of London, UK.
Neuropsychologia. 2020 May;142:107440. doi: 10.1016/j.neuropsychologia.2020.107440. Epub 2020 Mar 13.
Face recognition ability is often reported to be a relative strength in Williams syndrome (WS). Yet methodological issues associated with the supporting research, and evidence that atypical face processing mechanisms may drive outcomes 'in the typical range', challenge these simplistic characterisations of this important social ability. Detailed investigations of face processing abilities in WS both at a behavioural and neural level provide critical insights. Here, we behaviourally characterised face recognition ability in 18 individuals with WS comparatively to typically developing children and adult control groups. A subset of 11 participants with WS as well as chronologically age matched typical adults further took part in an EEG task where they were asked to attentively view a series of upright and inverted faces and houses. State-of-the-art multivariate pattern analysis (MVPA) was used alongside standard ERP analysis to obtain a detailed characterisation of the neural profile associated with 1) viewing faces as an overall category (by examining neural activity associated with upright faces and houses), and to 2) the canonical upright configuration of a face, critically associated with expertise in typical development and often linked with holistic processing (upright and inverted faces). Our results show that while face recognition ability is not on average at a chronological age-appropriate level in individuals with WS, it nonetheless appears to be a relative strength within their cognitive profile. Furthermore, all participants with WS revealed a differential pattern of neural activity to faces compared to objects, showing a distinct response to faces as a category, as well as a differential neural pattern for upright vs. inverted faces. Nonetheless, an atypical profile of face orientation classification was found in WS, suggesting that this group differs from typical individuals in their face processing mechanisms. Through this innovative application of MVPA, alongside the high temporal resolution of EEG, we provide important new insights into the neural processing of faces in WS.
面部识别能力通常被认为是威廉姆斯综合征（WS）患者相对较强的一项能力。然而，相关研究存在方法学问题，且有证据表明非典型的面部处理机制可能导致结果处于“正常范围”，这对这种重要社交能力的简单化描述提出了挑战。对WS患者面部处理能力在行为和神经层面进行的详细研究提供了关键见解。在此，我们对18名WS患者的面部识别能力进行了行为学特征分析，并与正常发育的儿童和成人对照组进行了比较。11名WS患者以及年龄匹配的正常成年人进一步参与了一项脑电图任务，他们被要求专注地观看一系列正立和倒立的面部及房屋图片。我们使用了先进的多变量模式分析（MVPA）以及标准的ERP分析，以详细描述与以下两点相关的神经特征：1）将面部作为一个整体类别进行观察（通过检查与正立面部和房屋相关的神经活动）；2）面部的标准正立配置，这在正常发育过程中与专业技能密切相关，且通常与整体处理（正立和倒立面部）相关联。我们的结果表明，虽然WS患者的面部识别能力平均未达到与其实际年龄相适应的水平，但在他们的认知特征中，这似乎仍是一项相对较强的能力。此外，所有WS患者在面对面部与物体时均表现出不同的神经活动模式，对作为一个类别的面部表现出独特的反应，并且正立和倒立面部的神经模式也有所不同。尽管如此，我们在WS患者中发现了非典型的面部方向分类特征，这表明该群体在面部处理机制上与正常个体存在差异。通过MVPA的这种创新性应用，以及脑电图的高时间分辨率，我们为WS患者面部的神经处理提供了重要的新见解。
