Automatic pupillary responses to pain perception in adults and children: The influence of race and autistic traits

This study used pupillometry to measure automatic physiological responses to painful facial expressions across 72 adults and children, finding that pupil dilation increased when viewing painful versus neutral expressions. Results showed both racial in-group bias and a negative correlation between autistic traits and empathic pupil dilation responses, suggesting pupillary responses may indicate automatic empathic arousal modulated by social group membership and autism-related differences.