Vision 2 - Depth Perception

Vocabulary flashcards covering depth perception, monocular, binocular, and oculomotor cues, vision constancies, and related optical illusions based on the lecture notes.

Depth perception

The brain's complex computation to see the world in 3D and determine object distances, despite retinal images being 2D.

Monocular cues

Cues for depth perception derived from the image of stimuli in one eye.

Binocular cues

Cues for depth perception that combine information from both eyes simultaneously.

Oculomotor cues

Cues for depth perception that infer distance from the behavior of the muscles around the eyes.

Interposition

A monocular cue where if one object hides parts of another, it is perceived as closer.

Texture gradient

A monocular cue where fine-grained texture appears closer, and less elaborated texture appears further away.

Shadows (depth cue)

A monocular cue where the direction, presence, or absence of shadows suggests which object is closer.

Linear perspective

A monocular cue where parallel lines seem to converge as they run into the distance, evoking an impression of depth.

Motion parallax

A monocular cue where closer objects seem to move faster and disappear quickly from the visual field compared to objects further away.

Binocular disparity

The difference in the visual input between the two eyes, which the brain analyzes to make inferences about object distance.

Horopter

The imaginary line where objects are seen in the same spatial location by both eyes when focusing on a particular point.

Panum-field

The region in space around the horopter where binocular fusion occurs.

Binocular fusion

The process by which the visual cortex combines the two slightly different views from each eye into a single, three-dimensional perception.

Convergence

An oculomotor cue where the eyes turn more inward as we look at closer objects.

Accommodation

An oculomotor cue where the muscles adjust the lens's shape to focus on a specific object, which can be used to infer distance.

Constancies

Learned perceptual mechanisms that allow us to recognize objects as having stable features (e.g., size, shape, color) despite variations in the retinal image.

Size constancy

The ability to judge objects as remaining the same size even though the size of their retinal image changes with distance.

Emmert's law

States that to infer an object's actual size from its retinal image size, the brain takes distance information into consideration.

Shepard Illusion (Example)

An illusion where two figures casting the same retinal image appear to have different actual sizes due to linear perspective providing depth cues, making the perceived 'further' object look larger.

Ponzo illusion

An illusion where two identical lines placed over converging lines appear to be of different lengths, with the line higher up (perceived as further away) appearing longer.