Attention-deficit/hyperactivity disorder (ADHD) often emerges in early childhood; however, objective validated biomarkers for its early detection remain limited. In this study, we aimed to identify pupil-based candidate physiological markers (i.e., physiological correlates) associated with ADHD-related traits in preschool- and early school-aged children. To this end, we recorded the pupil diameters of typically developing children without an ADHD diagnosis during a simple fixation task. From…
