How expertise can alter effects of face masks: investigating a sample of congenitally deaf participants?

A face mask covers the lower part of the face and thereby limits social communication. Only unoccluded face regions like the eyes and eye region remain informative in communication, which might be especially helpful for expert face readers such as the deaf population. We assessed the effects of face masks in a sample of 59 congenitally deaf participants. Participants rated faces with and without face masks for the following characteristics: arousal and valence of three facial expressions (happy, neutral, sad), invariant characteristics (sex, age), and trait-like characteristics (attractiveness, trustworthiness, approachability). The experiment was a replication of a previous study conducted on hearing participants. Results indicated that, when compared to no-masked faces, the deaf experienced reduced valence intensity in masked faces across all expressions. However, perceived arousal was only reduced for happy expressions in masked faces. Masked faces also appeared older and borderline more approachable. These results mostly mimicked data from the hearing, despite the deaf having greater expertise reading faces. Therefore, expert face readers also succumbed to the effects of face masks as the perceived intensity of facial expressions becomes reduced. An additional post-hoc analysis comparing the effects of face masks between deaf and hearing samples revealed distinct biases between the two populations. When evaluating facial expressions, the deaf showed stronger biases for full-faces than the hearing. When rating traits, the deaf were more biased by face masks whereas the hearing were more biased by full-faces. Implications for effects of expertise on face processing are discussed.

口罩覆盖面部下半区域，进而限制面部在社交沟通中的信息传递。此时仅眼部等未被遮挡的面部区域仍可传递有效沟通信息，这一现象对诸如聋人群体这类专业面部信息解读者而言可能尤为有益。本研究对59名先天性聋人参与者组成的样本开展实验，以评估口罩对面部认知的影响。参与者需对佩戴口罩与未佩戴口罩的面部，从以下维度进行评分：三种面部表情（快乐、中性、悲伤）的唤醒度（arousal）与效价（valence）、恒定属性（性别、年龄）以及特质类属性（吸引力、可信度、可亲近度）。本实验为一项针对听人参与者开展的既往研究的重复验证。结果显示，与未佩戴口罩的面部相比，聋人群体对佩戴口罩的面部的效价强度评分整体呈下降趋势，且覆盖所有三种表情类型。但仅在快乐表情的场景下，佩戴口罩的面部的唤醒度感知评分出现下降。此外，佩戴口罩的面部会被认为年龄更大，且在可亲近度维度上呈现出临界性的升高趋势。尽管聋人群体具备更出色的面部解读专长，但其实验结果与听人样本的数据整体趋势高度吻合。由此可见，即便为专业面部信息解读者，当面部表情的感知强度出现下降时，其认知也会受到口罩带来的负面影响。额外开展的事后分析（post-hoc analysis）对聋人与听人样本的口罩影响效应进行了对比，结果显示两类群体间存在显著的认知偏差差异。在评估面部表情时，聋人群体对完整无遮挡面部的认知偏差程度强于听人；而在对特质类属性进行评分时，聋人群体的评分更易受口罩遮挡的影响，听人则更易受完整面部的影响。本研究还讨论了面部解读专长对面部信息加工的影响所带来的相关启示。