Eye Movement Monitoring and Maturation of Human Face Exploration
Objective: The aim of this study was to characterize ocular exploration of neutral and emotional faces in the typical development of a child. Subjects and Method: In this eye-tracking study, visual exploration of faces (with neutral or emotional expressions: happiness or sadness) was characterized in a population of 52 children (24 girls and 28 boys from 4 to 15 years of age) and 44 adults (22 women and 22 men from 18 to 35 years of age). The time spent on the eyes, nose and mouth of the faces was measured. Results: All participants spent more time on the eyes (13%) rather than the nose and mouth (6%). The youngest participants spent less time exploring the eyes than the older participants, suggesting the progressive establishment of interest in these informative regions of the face during maturation. This process seemed to occur later in females (7-9 years) than males (4-6 years). Conclusion: These results confirm the importance of the eye area and the capacity of this region to capture attention. In addition, this study shows that the exploration of this region increases with age and is lower among girls aged 4-6 years compared with boys of the same age.