Children's Perceptual Sensitivity to Optic Flow-Like Visual Motion Differs From Adults

Observers experience complex patterns of visual motion in daily life due to their own movements through space, the movement of objects, and the geometry of surfaces in the visible world. Motion information shapes behavior and brain activity beginning in infancy. And yet most prior behavioral research has focused on how children process only one type, linear motion, leaving largely unexplored how children respond to radial or rotational motion patterns that co-occur with linear motion in everyday visual experience. This study examined how children and adults detect linear and radial motion patterns corrupted by a range of noise levels. Five to eight-year-old children (n = 25, 16 females; 76% White, 4% Asian, 16% more than one, 4% unknown) and young adults (n = 29, 15 females; 83.33% White, 16.67% Asian) viewed pairs of radial and linear motion displays mixed with random noise at one of two speeds (2 deg/s or 8 deg/s). Participants selected the display with coherent motion. Children and adults showed higher accuracy (percent correct) to radial versus linear motion patterns. Children had higher accuracy to the faster speed, while adults showed the opposite pattern. Adults showed better performance than children in all conditions. Exploratory analyses showed that male children had higher accuracy than their female peers. We conclude that motion processing develops in childhood with separable developmental trajectories for the processing of slow and fast visual motion, and that while further investigation is warranted, sex differences in motion processing found in young and older adults may begin in middle childhood.