AP Psych - 16. Perception

Selective Attention

what we are continuously focusing on

Cocktail Party Effect

attending to one auditory message while filtering others out

Selective Inattention

consciously or unconsciously ignoring stimuli

Change Blindness

failing to notice obvious changes in the environment when there is a break in your field of vision

Perception

how our brain, interprets, makes sense of & organizes sensory info

Bottom-Up Processing 

• sensation first, then perception 

• parts 🡪 whole 

• focus on raw sensory info, then form perception 

• common with new/unfamiliar stimuli

Top-Down Processing 

• perception first, then sensation

• whole 🡪 parts 

• based on our experiences, expectations, culture, norms  

• schema, perceptual/mental set 

Schema

mental category that helps us organize the world

Assimilation

placing info into an existing schema (top-down)

Perceptual Set 

• aka mental set

• mental predisposition to perceive one thing and not another

• experiences, expectations, motivations, emotions, culture

• lenses that shape our perception

 Muller-Lyer Illusion

an example of context & expectation impacting perception 

Perceptual Constancies 

perceive objects as unchanging even as changes occur in our field of vision (size, shape, color) 

Gestalt Psychology

• german for “whole”

• our brains make complete images out of stimuli & tend to group stimuli (closure, proximity, similarity & figure-ground)

Figure-Ground Relationship

• most commonly on exam

• another gestalt principle

• brains automatically tries to perceive objects as distinct from the background

• what is in the background vs. the foreground?

Depth Perception 

• ability to determine how near or far an object is from us 

• innate 

• depth cues – how we see 2D images and perceive depth/3D

Binocular Depth Cues

• depth cues that require the use of BOTH eyes

• strongest depth cues

Retinal Disparity

• our brain takes the slightly varying images cast on our retinas in both eyes to perceive depth 

• large disparity (difference) – closer the object 

• small disparity – further the object 

Convergence

the inward rotation of both eyes to focus on a nearby point, allowing for a single, fused image

Monocular Cues

depth cues with one eye

Relative Size

perceive distance from an object that appears smaller

Linear Perspective

• parallel lines appear to come together in the distance

• the more the lines merge together, the further distance we perceive 

Ponzo Illusion

linear perspective creates an optical illusion (railway track w/ yellow lines)

Interposition

when an object partially blocks another, we perceive the object ‘blocking’ the other as closer 

Relative Clarity

hazier/fuzzy objects appear more distant

Texture gradient

using pattern to give the impression of depth

Apparent Motion

when a stationary object seems to move

Stroboscopic Movement

• form of apparent motion

• a rapid series of slightly varying images (often used in movies, cartoons)

Phi Phenomenon

illusion of movement created when two or more adjacent lights blink on and off in quick succession

Sensory Adaptation

• aka neural adaptation

• can only bring back the pink spots from light if you more your eyes