Pupillary responses to masked and gaze-averted faces

Area of Science:

• Cognitive Psychology
• Human-Computer Interaction (HCI)
• Neuroscience

Background:

• Face masks, prevalent during COVID-19, influence emotion recognition by obscuring facial features.
• Gaze direction is crucial for emotion identification, particularly when faces are partially covered.
• The physiological underpinnings of how masks and gaze affect emotion processing remain underexplored.

Purpose of the Study:

• To investigate the combined effects of face masks and gaze direction on emotion recognition.
• To explore the role of pupillometry in understanding cognitive processes during masked emotion perception.
• To assess how pupil size changes relate to accuracy and errors in emotion identification.

Main Methods:

• Utilized pupillometry to measure pupil size changes in 40 participants.
• Presented participants with images of faces displaying anger, fear, or neutral emotions.
• Manipulated gaze direction (direct, averted) and face mask conditions (mask, no mask).

Main Results:

• Behavioral accuracy confirmed the importance of the eye region for anger/neutral recognition and direct gaze benefits.
• Averted gaze improved fear recognition, aligning with prior research.
• Pupil dilation significantly increased with recognition errors, particularly for masked fearful faces, suggesting heightened cognitive load and ambiguity.

Conclusions:

• Pupil dilation serves as a physiological indicator of cognitive effort in emotion identification, especially under challenging conditions like masked faces.
• Participants employed compensatory strategies, relying more on gaze and visible cues when masks obscured facial information.
• Findings offer insights for developing adaptive support systems in HCI and VR to enhance user experience by accounting for cognitive load.