AP Psych Sensation and Perception

sensation

process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

perception

process of organizing and interpreting sensory information enabling us to recognize meaningful objects and events

absolute threshold

minimum amount of stimulus energy needed to detect a particular stimulus 50% of the time

difference threshold

minimum difference between two stimuli required for detection 50% of the time

Weber’s law

two stimuli must differ by a constant percentage rather than a constant amount

sensory adaption

diminished sensitivity as a consequence of constant stimulation or exposure

synesthesia

neurological condition in which stimulation of one sense leads to automatic experiences in a second sensory system

transduction

converting sensory stimulation into neural signals

3 steps of transduction

receive sensory stimulation, transforming that stimulation into neural impulses, and deliver those impulses to brain

process of eye

cornea, pupil, iris, lens, retina, optic nerve

cornea

eye’s clear, protective layer

pupil

adjustable opening of the eye allowing light to pass through

iris

colored ring of muscle tissue

lens

transparent structure which changes shape to focus images

retina

light sensitive inner surface of the ey with layers of neurons to convert light into neural impulses

optic nerve

neural impulses are carried to brain via this

accommodation

process of focusing these images

rods

retinal receptors that detect black, white, and gray, sensitive to movement in peripheral

cones

retinal receptors near center around fovea sees color/daylight

blind spot

the point at which optic nerve exits the eye so there is an absence of receptor cells

fovea

central ocal point in retina and cones cluster here

ganglion cells

final output neurons of the retina which collects the electrical messages concerning the visual signal from the two layers of nerve cells preceding it

bipolar cells

transport information from rods and cones to ganglion cells

young-helmholtz trichromatic theory

states that retina has three basic colors red, green, blue and can be combined to create every color

opponent-proces theory

color vision depends on three sets of opposing retinal process - red-green, blue-yellow, and white-black.

light wavelength

determines hue/color

light amplitude

color intensity

sound wavelength

pitch

sound amplitude

volume

prosopagnosia

neurological disorder characterized by the inability to recognize faces

blindsight

can’t see but can make sense of the objects in their environment

audition

sense of hearing

process of ear

pinna, auditory canal, eardrum, hammer/anvil/stirrup, cochlea

cochlea

coiled, bony, fluid-filled tube of inner ear responsible for transduction of sound

basilar membrane

layer of hair cells which convert the sound waves into neural impulses

auditory nerve

carries neural impulses to brain

sensorineural hearing loss

inability to hear due to damage to the cochlea’s receptor cells or to the auditory nerves

conduction hearing loss

inability to hear due to damage to mechanical elements of the ear

place theory

high pitches - due to activation of specific hair cells on the basilar membrane

frequency theory

low pitches - entire basilar membrane vibrates in response to sound

process olfaction (sense of smell)

odorants enter nasal cavity, 5 million receptors in olfactory bulb, goes straight to temporal lobe

semicircular canals

fluid-filled tubes used by the vestibular sense to sense body position

middle ear

transmits sound waves from eardrum to inner ear

gustation (taste)

sweet, sour, salty, bitter, umami, oleogustus

sensory interaction

ability of one sense to influence or interact with another (smell + taste)

touch

pain, pressure, touch, and temperature, processed by parietal lobe

bottom-up processing

analysis that begins with the sensory receptors and works up to the brains integration of sensory information

top-down processing

information processing guided by higher-level mental process, as when we construct perceptions drawing on our experiences and expectations

perceptual set

mental predisposition to perceive one thing and not another

Gesalt

perception as an integrated whole

proximity

group object that are close together as being part of the same group

similarity

objects similar in appearance are perceived as being part of same group

continuity

objects form a continuous shape are perceived as same group

connectedness

elements tend to be group together if they are connected by other elements and view as a single unit

closure

we fill gaps in if we can recognize it

figure ground

organization of the visual field into objects that stand out from their surroundings

selective attention

focusing our conscious awareness on a particular stimulus

cocktail party effect

ability to focus one’s attention on a particular stimulus while filtering out a range of other stimuli

inattentional blindness

failing to see visible objects when our attention is focused elsewhere

change blindness

failing to notice changes in the environment

depth perception

depth perception is partially innate

perceptual constancy

ability to perceive objects as unchanging even as illumination and retinal images change

perceptual adaption

if your perception is altered for any reason, your brain will work to overcome this shift using previous memories

stroboscopic effect

rapid series of slightly varying images perceived as motion

phi phenomenon

illusion of movement created when two or more light next to each other blink on and off

autokinetic effect

perceptual phenomenon where a stationary point of light appears to move in a dark environment due to small eye movements

afterimage effect

visual illusion where you see an image after the stimulus is gone

kinesthesis

sense that provides awareness of the position, movement, and action of one’s body parts

signal detection theory

explains how we perceive a faint signal amidst background “noise” and it involves both sensory process and psychological factors like motivation and attention

pain sensations

an unpleasant sensory and emotional experience linked to actual or potential tissue damage

gate control theory

explains how spinal cord can modulate pain

phantom limb pain

brain continues to perceive sensations from a missing limb

biopsychological approach to pain

views pain as the result of an interaction between biological, psychological, and social factors.