 Humans are constantly making decisions about spatial relations; however, some spatial relations, such as left-right, are commonly confused, while other spatial relations, such as up-down, above-below, and front-back, are seldom, if ever, mistaken.The ability to categorize and compartmentalize space is an essential tool for navigating this 3D world; an ability shown to develop in early infancy.Infant ability to visually match above-below and left-right relations appears to diminish in early toddlerhood, as language acquisition may complicate verbal labeling.