Perception: The Story of Shape

Vocabulary flashcards based on lecture notes about shape perception, strabismus, and depth cues.

Strabismus

A condition caused by impairment in the functioning of eye muscles, often congenital and with a genetic element.

Binocular Disparity

The difference in images seen by the left and right eyes, providing information about depth and 3D structure.

Lens Accommodation

The process by which the eye changes focus to maintain a clear image, effective up to 1 meter.

Ocular Convergence Angle

The angle formed by the eyes when focusing on an object, effective up to 6 meters.

Declination from Eye Level

A distance cue effective from 5 to 20 meters, based on the position of an object relative to the eye level.

Motion Parallax

A depth cue resulting from the relative motion of objects at different distances when the observer moves.

Relative Depth Cues

Visual cues such as shading, interposition, and relative size that provide information about 3D shape and layout.

Accommodation

The process by which the eye's lens changes shape to focus on objects at varying distances.

Convergence

The inward movement of the eyes when focusing on a near object.

Depth of Focus Blur

The range of distances within which objects appear in focus.

Declination from eye level

A depth cue where the perceived distance of an object correlates with its position relative to eye level.

Ground-plane information

Visual information derived from the texture and perspective of the ground surface, providing cues to distance and spatial layout.

Exocentric Distance

The distance between two objects in space, independent of the observer's viewpoint.

Egocentric Distance

The distance from the observer to an object.

Primary Visual Cortex (V1)

The first cortical area to receive visual input, responsible for encoding simple components of shape such as points, lines, and curves.

Temporal Cortex

A higher-level visual area involved in encoding more complex shapes and recognizing objects.

Fusiform Face Area (FFA)

A region in the inferior temporal cortex that shows selectivity for face shapes.

Lateral Occipital Cortex (LOC)

A region in the visual cortex that is selective for object shapes.

Amodal Completion

The perception of a partially occluded object as complete despite the missing visual information.

Modal Completion

The perception of illusory contours or surfaces that are not physically present.

Edge Relatability Criterion

A geometric condition used in models of contour completion to determine whether two edges are likely to belong to the same object.

Medial Axis Representation

A method for representing shape based on the set of points equidistant from the boundaries of the shape, also known as the Blum transform.