By the time they are four months old, most babies can organize visual information in at least three ways: by brightness, by shape and by how close together objects are. Emily Farran, a psychologist at the University of Reading in England, tested infants by showing them images on a computer screen while cameras tracked how long they gazed at various patterns. Her results indicate that perception of brightness emerges first, by two months, in line with previous work. By four months, most infants can group objects by shape and proximity, too. “Earlier research had shown only the ability to group by shape at six to seven months,” Farran says, “and we believe we are the first to show grouping by proximity.”