What visual skill might be assessed using a depth perception test?

Depth perception tests are specifically designed to assess a person’s ability to perceive the world in three dimensions and to judge distances accurately. This ability is heavily reliant on stereopsis, which is the perception of depth that arises from the slightly different angles of view from each eye, combined into a single three-dimensional image in the brain.

By using cues such as binocular disparity—the difference in images seen by each eye—stereopsis allows individuals to grasp how far away objects are. Depth perception tests may involve asking patients to identify which of two objects is closer or more distant, making it a direct measure of stereoscopic ability.

Other visual skills, such as visual acuity, color vision, and contrast sensitivity, are important for different aspects of visual function, but they do not directly assess depth perception. For instance, visual acuity measures clarity of vision, color vision assesses the ability to distinguish colors, and contrast sensitivity evaluates how well a person can discern between varying shades of light and dark. None of these directly measure the ability to perceive depth in the way that stereopsis does.