Grace Wallsinger¹ (), Maeve R. Boylan¹, Ryan Barry-Anwar¹, Lisa S. Scott¹; ¹University of Florida

Preschool-aged children have been found to demonstrate superior recognition of own-race faces. However, the developmental trajectory of the categorization of face sex and race during the preschool years is not well understood. The present study examined neural categorization of sex and race in children aged 3-5 years using Fast Periodic Visual Stimulation (FPVS). Continuous EEG was recorded while faces from one category were presented at a frequency of 6 Hz (the standard category). Every 5th face was a face from a different category (the oddball category presented at 1.2 Hz). We tested 4 types of categorization: 1) race categorization within male faces, 2) race categorization within female faces, 3) sex categorization within familiar-race faces, and 4) sex categorization within unfamiliar-race faces. Race group familiarity was coded for each participant based on a parent-completed questionnaire about the racial identities of people their child frequently interacts with. It was predicted that children would show robust evidence of neural categorization within the most commonly experienced groups (female faces and familiar-race faces) and that older children would show stronger effects than younger children. Results reveal a main effect of race group familiarity for the 6 Hz response, with increased amplitudes for familiar-race faces compared to unfamiliar-race faces. Additionally, a robust 1.2 Hz response was observed across all conditions, demonstrating children’s ability to differentiate between face categories. This 1.2 Hz response was also modulated by face familiarity, with larger responses for familiar-race faces. Preliminary topographic analyses of the 1.2 Hz response show significant medial and right occipitotemporal activity - further highlighting the role of familiarity in shaping neural responses to faces. These findings suggest that prior familiarity with certain face group categories influences both the general visuocortical face processing response and the neural categorization of faces during childhood.