Recognition of masked faces demonstrates the rigidity of the face processing system throughout development

• In Event: Face masks and socioemotional development: Multimodal research on emotion processing of masked faces

Abstract

Face perception is considered a remarkable visual ability in humans that is evident early in life but is then subject to a prolonged developmental trajectory. In response to the COVID-19 pandemic, mask-wearing has become mandatory for adults and children alike. This abrupt, but nevertheless consistent, alteration in human behaviour across countries and societies provided a unique opportunity to examine the adaptability of the face processing system to changes across ages. In my talk, I will describe a series of investigations that were designed to address this critical question. Across the different studies, we utilized the Cambridge Face Memory Test (CFMT), a validated measure of face perception performance. Faces were presented with or without masks and across two orientations (upright/inverted).

In the first study, we directly compared the effect of masks on face perception in school-age children (n = 72, ages 6-14 years old) and adults. The inclusion of face masks led to a profound deficit in face perception abilities. This decrement was more pronounced in children than adults, but only when task difficulty was adjusted across the two age groups. In addition to these quantitative changes, children and adults demonstrated qualitative differences in processing masked vs. non-masked faces. Specifically, holistic processing, a hallmark of face perception, was disrupted for masked faces as suggested by a reduced face-inversion effect.

Next, to further explore the adaptability of the face processing system, we investigated whether the face-mask effects would be attenuated following extended natural exposure. We conducted a large-scale cross-sectional study (N = 1,732 adults) at six different time points over a 20-month period, alongside a 12-month longitudinal study (N = 208). The results of the experiments revealed persistent deficits in recognition of masked faces and no sign of improvement across time points. Additional experiments verified that the amount of individual experience with masked faces was not correlated with the mask effect. Interestingly, this lack of improvement was also observed in school-age children (N=144), who displayed a consistent deficit in recognizing masked faces and a reduced inversion effect.

Together, this research program provides compelling evidence for the susceptibility of the visual system to changes in the appearance of faces. This susceptibility might be enhanced early in life, reflecting the immaturity of the face processing system. Finally, we also conclude that the face processing system of adults and children alike does not easily adapt to visual changes in face stimuli, even following prolonged real-life exposure.

Author

• Erez Freud, York University
  Presenting Author