An investigation on the face inversion effect in deaf children

The face inversion effect is an important indicator of holistic face perception and reflects the developmental level of face processing. This study examined the face inversion effect in deaf or hard of hearing (DHH) children aged 7-17 using the face dimensions task. This task uses photographic images of a face, in which configural and featural information in the eye and mouth regions have been parametrically and independently manipulated. The study aimed to discuss the effect of face inversion on facial processing in DHH children, including two aspects of information processing types (configural versus featural) and processing regions (eyes versus mouth) and compared the results with hearing children. The results revealed that DHH children aged 7-17 years exhibit significant face inversion effect, with disruptions observed in both the featural and configural processing of eyes and mouths when faces were inverted. Configural processing was more affected by inversion than featural processing in all children, with larger differences observed in DHH children than in hearing children. This supports the dual-mode hypothesis of holistic face processing. Age correlations were observed in the sensitivity of DHH children to face inversion effect but not among hearing children. The inversion effect of configural mouth processing decreases with age in DHH children.