Perception

Perceptual Organization Closure: we see the whole picture, even if there are gaps

Perceptual organization Figure-Ground: seeing figures against a background **What we perceive as the figure vs. background influences our perception

Perceptual Organization Proximity: we group things by closeness Similarity: We group similar (like) objects together

Perceptual Organization Continuity: We prefer to see smooth continuous patterns Common Fate: things move together, belong together

Movement The perception of movement is relative to other objects Stroboscropic motion: illusion of movement by the quick progression of still images

Depth Perception Depth means distance away Monocular cues: (one eye) create the illusion of 3D on flat surfaces

Monocular cues

Monocular cues same size objects look different if placed at different distances clearer an object, the nearer it seems Nearer objects block further objects Shadows and highlights give depth perception

Depth Perception Binocular Cues: (2 eyes) Retinal disparity: image on BOTH eyes seen at dif angles Convergence: Tension in our eyes as we focus on an object getting closer to us

Perceptual Constancies Size Constancy: Perceive an object as being 1 size no matter how far away Color Constancy: Color stays the same even in different light Shape Constancy: Shapes stay the same, even at dif angles Brightness Constancy: Judge brightness on the color of objects around it

Visual Illusions Muller-Lyer: we are reminded of building structure: We perceive in-facing arrows as longer

Visual Illusions Ponzo Illusion: Size constancy makes us think the top line is longer + further away

Practice Look at the selected illusions with 3 or 4 other students. Discuss what perceptual principles are at work with your illusions.

Exit Slip 1. Pick one illusion. 2. Describe it or sketch it. 3. Identify all the perceptual principles in the illusion.