What are the monocular cues used for depth perception?

Monocular cues are visual indicators that allow us to perceive depth using only one eye. Among the options provided, the concept of "GRAM," which stands for Gradient, Relative Size, Aerial Perspective, and Motion Parallax, is particularly relevant for understanding depth perception.

Gradient refers to the change in texture or density as objects recede into the distance. Relative Size helps with depth cues by comparing the size of known objects; smaller objects tend to be perceived as farther away. Aerial Perspective involves the effect of the atmosphere on distant objects, where they appear hazier and less saturated than nearby objects. Lastly, Motion Parallax describes how objects closer to us move faster across our field of view compared to those further away, giving a sense of depth based on relative motion.

These cues work together to help the brain interpret three-dimensional space, making GRAM a comprehensive framework for understanding depth perception with just one eye. Other listed options may include elements that contribute to our perception in different capacities, but they do not encapsulate the complete set of monocular depth cues as effectively as GRAM does.