Perception

Perception

Rules of Perceptual Organization

Gestalt PsychologistsThe whole is more than the

sum of its partsClosure

Even if there are gaps in a picture we will see the object

Rules of Perceptual Organization

Figure Ground PerceptionThe perception of figures

against a backgroundWhat we see as the figure

and the background shape our perception

Rules of Perceptual Organization

ProximityObjects that are close to one

another are paired together for no reason other then their closeness

SimilarityObjects that are similar to one

another are grouped together

Rules of Perceptual Organization

ContinuityObjects are viewed as

continuing pattern rather then broken apart segments

Common FateObjects moving together

belong together

Perception of Movement

To perceive an object is moving you must view it relative to another objectExamples

Earth’s movementMovement of a car

Stroboscopic Motion

Movements that are not actually in motion are movingFlip bookMovie

Depth Perception

The distance away from youPerceived through monocular

and binocular cues

Depth Perception – Monocular CuesNeed one eye to be perceived Creating the illusion of three

dimensionsPaintingsPerspective

Objects in the distance appear smaller

Parallel lines appear to get closer together

Depth Perception – Monocular Cues

ClearnessThe clearer an object the closer it appears to be

OverlappingObjects that are partially covered are perceived to be further away

Depth Perception – Monocular Cues

ShadingHighlighted areas are perceived as being closer to you

Texture GradientObjects that are closer have more and varied texture

Depth Perception- Monocular Cues

Motion ParallaxThe tendency of objects to move forward or backwards depending on their distanceExample: as you drive in your carMoon moves forward Trees move backwards

Depth Perception – Binocular Cues

Requires both eyes for perceptionRetinal disparity

Seeing double of your finger as you bring it towards you

An image of the finger is projected onto each retina

Serves as a cue for depth within a few feet

Depth Perception – Binocular Cues

Convergence Feeling of tension in eye muscles

Feeling of convergence is greater as an object gets closer

Perceptual Constancies

Created by experienceSize Constancy

The tendency to perceive object as being one size regardless of how far away they are

Perceptual Constancies

Color ConstancyPerceiving an object as

remaining the same color even through different exposure to light

Brightness ConstancyTendency to perceive an object

as being equally as bright even when the light around it changes

Perceptual Constancies

Shape ConstancyPerception that an object has the

same shape regardless of the angle at which you view it

Visual Illusions

Muller – Lyer illusionWe perceive the lines as

corners of a buildingOur brain reasons the corner

of the room must be larger because it is further away

Visual Illusion

Ponzo illusionConverging lines strike us as

receding into the distanceThe rule of size constancy

comes into play

http://educ.jmu.edu/~johns2ja/illusion/illusion.htm#mcdpool