Children's Automatic Processing of Adult Face Aggression Cues

The detection of threatening information conveyed by faces is crucial for human survival and development, especially for children. Previous research has shown that adults perceive faces with a high facial width-to-height ratio (fWHR) as more aggressive and process this information automatically. However, it is unclear whether children possess similarly. In this study, two experiments were conducted with children aged 9–11 to explore their ability to perceive aggression based on fWHR and whether they automatically process this information. In Experiment 1, children were asked to rate the perceived level of aggression in adult faces with high and low fWHR. It was found that high fWHR faces were perceived as more aggressive than low fWHR. In Experiment 2, visual mismatch negativity (vMMN) was used as an indicator to explore automatic processing further in an oddball paradigm. Children were asked to detect fixation size while being presented with adult faces with high or low fWHR in the background. It was observed that high fWHR faces induced vMMN in the 270–330 ms time range, while low fWHR faces did not, suggesting that children are able to automatically process high fWHR faces but not low fWHR. These results suggest that children can detect aggression cues through fWHR and automatically process high fWHR faces.