sensation and perception

Absolute threshold

Minimum stimulus detectable 50% of the time; hearing a faint beep

Accommodation

Lens changes shape to focus; eyes adjust from far to near object

Afterimages

Visual images seen after stimulus removed; seeing a spot after bright light

Amplitude

Height of wave; loud sound has higher amplitude

Apparent movement

Perceived motion from stationary images; movies

Attention

Focusing on specific stimuli; listening in class

Auditory canal

Pathway to eardrum; sound travels in ear

Basilar membrane

Inner ear membrane; detects pitch

Binocular depth cues

Using both eyes for depth; seeing distance between two objects

Blindsight

Responding to visual info without conscious awareness; navigating obstacles blindfolded

Blind spot

Area without photoreceptors; small gap in vision

Bottom-up processing

Processing from senses first; identifying a shape as a triangle

Change blindness

Failing to notice changes in environment; missing changed poster

Closure

Mind fills gaps; seeing a complete circle from broken lines

Cochlea

Spiral in inner ear; converts sound to neural signals

Cocktail party effect

Focusing on one voice in noise; hearing name in crowd

Color blindness

Unable to see certain colors; red-green blindness

Conduction deafness

Ear damage blocks sound; broken eardrum

Cones (blue, green, red)

Color photoreceptors; detecting colors

Convergence

Eyes angle inward for close objects; cross-eyed looking at pencil

Cornea

Transparent front eye layer; bends light

Dichromatism

Two-color deficiency; red-green colorblindness

Eardrum

Vibrates from sound; middle ear membrane

Farsightedness

Cannot see close objects clearly; holding book far away

Figure and ground

Organizing visual field; seeing text vs background

Fovea

Center of retina; sharpest vision

Frequency theory

Pitch from firing rate; high sound = fast firing

Ganglion cells

Retina cells; transmit visual info to brain

Gate control theory

Pain controlled by spinal “gate”; rubbing hurts less

Gestalt psychology

Perceiving whole patterns; seeing a face, not dots

Gustation

Taste sense; tasting sweet candy

Inattentional blindness

Failing to notice visible objects; not seeing gorilla in video

Interposition

Closer objects block farther ones; tree in front of house

Just-noticeable difference

Smallest detectable change; noticing volume change

Kinesthesis

Body movement sense; knowing arm position with eyes closed

Lens

Focuses light on retina; changes shape for near/far

Linear perspective

Parallel lines appear to converge; railroad tracks

Loudness

Perception of amplitude; whisper vs shout

Medium tasters

Average taste sensitivity; tasting sweetness normally

Monochromatism

Only sees shades of one color; rare total color blindness

Monocular depth cues

One-eye cues; relative size

Nearsightedness

Cannot see far; blurry street signs

Nontasters

Low taste sensitivity; weak bitter taste

Olfactory system

Smell receptors; detecting perfume

Opponent-process theory

Color perception from opposing pairs; red-green, blue-yellow

Ossicle bones

Middle ear bones; transmit sound

Perceptual set

Expectation shapes perception; seeing faces in clouds

Phantom limb

Sensation of amputated limb; feeling missing hand

Pheromones

Chemical signals; detecting attraction

Photoreceptors

Cells detecting light; rods & cones

Pitch

High or low sound; soprano vs bass

Pitch perception

How we interpret pitch; recognizing a note

Place theory

Pitch depends on where cochlea stimulated; high notes = base

Prosopagnosia

Face blindness; cannot recognize familiar faces

Proximity

Objects near each other grouped; dots form a line

Relative clarity

Far objects hazy; mountains appear foggy

Relative size

Larger = closer; people in distance smaller

Retina

Light-sensitive layer; contains photoreceptors

Retinal disparity

Difference in each eye image; depth perception

Rods

Detect light/dark; night vision

Schema

Mental framework; knowing what a dog looks like

Selective attention

Focusing on one stimulus; listening in noisy room

Semicircular canals

Inner ear balance; spinning triggers dizziness

Sensation

Detecting stimuli; feeling a touch

Sensorineural deafness

Nerve damage; cochlear nerve injury

Sensory adaptation

Sensitivity decreases over time; stop noticing perfume

Sensory interaction

Senses affect each other; smell enhances taste

Similarity

Group similar objects; seeing pattern in dots

Sound localization

Finding sound source; hearing car behind you

Supertasters

Extremely sensitive taste; bitter foods intense

Sweet, sour, salty, bitter, umami, oleogustus

Taste types; tasting chocolate sweet

Synesthesia

One sense triggers another; hearing colors

Taste receptors

Detect flavors; tongue cells

Thalamus

Relay station; sends sensory info to cortex

Top-down processing

Using experience to interpret senses; reading messy handwriting

Transduction

Converting stimuli to neural signals; light → vision

Trichromatic theory

Color perception from 3 cones; RGB detection

Vestibular sense

Balance; spinning feeling dizzy

Visual/optic nerve

Sends visual info to brain; retina → brain

Volley theory

Pitch via neuron firing in groups; mid-range tones

Volume

Perceived loudness; whisper vs shout

Warm/cold receptors

Temperature sense; hot bath

Wavelength

Distance between waves; color hue or pitch

Weber’s law

Detectable difference proportional; noticing weight change