University of Lincoln, UK.
Perception. 2021 Apr;50(4):328-342. doi: 10.1177/03010066211000270. Epub 2021 Mar 12.
We often show an invariant or comparable recognition performance for perceiving prototypical facial expressions, such as happiness and anger, under different viewing settings. However, it is unclear to what extent the categorisation of ambiguous expressions and associated interpretation bias are invariant in degraded viewing conditions. In this exploratory eye-tracking study, we systematically manipulated both facial expression ambiguity (via morphing happy and angry expressions in different proportions) and face image clarity/quality (via manipulating image resolution) to measure participants' expression categorisation performance, perceived expression intensity, and associated face-viewing gaze distribution. Our analysis revealed that increasing facial expression ambiguity and decreasing face image quality induced the opposite direction of expression interpretation bias (negativity vs. positivity bias, or increased anger vs. increased happiness categorisation), the same direction of deterioration impact on rating expression intensity, and qualitatively different influence on face-viewing gaze allocation (decreased gaze at eyes but increased gaze at mouth vs. stronger central fixation bias). These novel findings suggest that in comparison with prototypical facial expressions, our visual system has less perceptual tolerance in processing ambiguous expressions which are subject to viewing condition-dependent interpretation bias.
我们经常在不同的观察环境下对典型的面部表情（如快乐和愤怒）表现出不变或可比的识别性能。然而，在退化的观察条件下，模糊表情的分类和相关的解释偏差在多大程度上是不变的，这还不清楚。在这项探索性的眼动追踪研究中，我们系统地操纵了面部表情的模糊性（通过不同比例的变形快乐和愤怒表情）和面部图像的清晰度/质量（通过操纵图像分辨率），以测量参与者的表情分类表现、感知的表情强度，以及相关的面部注视分布。我们的分析表明，增加面部表情的模糊性和降低面部图像的质量会引起表情解释偏差的相反方向（负面偏差与正面偏差，或增加愤怒分类与增加快乐分类），对评定表情强度的影响方向相同，以及对面部注视分配的定性不同的影响（眼睛注视减少，但嘴巴注视增加，或中央注视偏置增强）。这些新发现表明，与典型的面部表情相比，我们的视觉系统在处理易受观察条件影响的模糊表情时，感知容忍度较低，这些表情会产生依赖于观察条件的解释偏差。
