Perception & Attention

Selective attention

Focusing awareness on one stimulus while ignoring others.

Cocktail party effect

Ability to attend to one voice in a crowd while noticing your name spoken elsewhere.

Inattentional blindness

Failing to see visible objects when attention is elsewhere.

Change blindness

Failure to notice changes in environment.

Perceptual set

Mental predisposition to perceive something a certain way.

Gestalt

Psychology principle: “the whole is greater than the sum of its parts.”

Figure-ground

Organizing visual field into figure (object) and ground (background).

Grouping

Perceptual tendency to organize stimuli into groups (proximity, similarity, continuity, closure).

Depth perception

Ability to perceive 3D and judge distance.

Visual cliff

Lab test showing infants’ depth perception using glass “drop-off.”

Binocular cue

Depth cue requiring both eyes (retinal disparity, convergence).

Convergence

Inward angle of eyes when viewing something close.

Retinal disparity

Brain compares slightly different images from each eye to perceive depth.

Monocular cues

Depth cues available to one eye (e.g., linear perspective, interposition).

Stroboscopic movement

Rapid series of images perceived as motion (flipbook effect).

Phi phenomenon

Illusion of movement from blinking lights in succession.

Autokinetic effect

Stationary light in dark appears to move.

Perceptual constancy

Perceiving objects as unchanging despite changes in view.

Color constancy

Perceiving familiar objects as same color under different lighting.

Perceptual adaptation

Ability to adjust to altered vision (like inverted goggles).