sensation

sensation

activation of sense

perception

process of understanding sensations

visible light

light reflected off objects to our eyes, only small section of electromagnetic spectrum

hue

light wavelength show colors

color perceive

light intensity, how bright object is

cornea

reflected light enters, protective covering to focus on light

pupil

shutter, iris contracts pupil

iris

muscles that control pupil open or close to regulate amount of light entering

accommodation

eye lens change shape to focus near or feat, 

lens

light that enters the pupil is focused by lens, curved and flexible to focus on light

retina

screen in back of eye, inverted project on retina

photoreceptors

rods and cones

cones

color, center of retina

rods

black and white, more than cones

fovea

very center of retina has indent, a lot of cones

peripheral vision

everything you see without moving your head

ganglion cells

make up optic nerve, outermost layer

bipolar cells

in between rods + cones and ganglion cells

blindspot

spot optic nerve leaves retina

optic chasm

point where optic nerves intersect in the brain

LGN

region in thalamus that send impulses from optic nerve

feature detectors

cells in visual cortex that respond to features of stimuli (angles, edges, length, movement)

trichromatic theory

three colors of RGB in cones, mixed together in brain show combined colors

opponent process theory

sensory receptors in retina are in pairs, stimulate one pair, the other inhibited

after image

stare at a color, opposite pair appears in blank space

color blindness

missing one pair of colors

color pairs

red + green, yellow + blue, black + white

audition

how our ears process sound waves

sound waves

created by vibrations, amp and freq

amp

height of wave, loudness of sound

freq

length of waves, pitch

external ear

pinna (can see part of ear) to ear canal to eardrum
ear canal: sound waves travel through it

ear drum

turn into vibrations, thin sheet at end of ear canal

middle ear

three bones, HAS (hammer, anvil, stirrup), then to oval window (attached to cochlea)

inner ear

cochlea, basilar membrane, organ of corti

cochlea

snail thing, vibration of oval window cochlea fluid

basilar membrane

hair cells connected to organ of corti

organ of corti

neurons activated by movement of hair, to brain by auditory nerve

place theory

place in cochlea that respond to different freq, hair cells move in different places

freq theory

rate of nerve impulses fire differently up the auditory nerve

conduction deafness

external and middle ear damage

sensorineural deafness

inner ear, hair cells in cochlea damages, due to loud noise, old

nerve ends

pressure or temp, brain determine had intensity of touch

pain

warns of potential dangers

gate control theory

in spinal cord, higher priority to pain messages, lower priority gets ignored and we don't feel

taste buds

all over mouth, sweet, salty, sour, bitter, umami

umami

delicious savory taste

papillae

bumps on tongue that have taste buds

smell

molecule -> nostril -> receptor cells -> olfactory bulb -> info to brain -> amygdala -> hippocampus

vestibular sense

overall body position through semicircular canals in ear, balance (upright, sideways, upside down)

kinesthetic sense

position of where body parts are

absolute threshold

small amount of stimulus can detect 50% of the time

subliminal

not in our conscious, below absolute threshold

difference threshold

just noticeable difference, minimal difference when 2 stimuli is req for detection

weber’s law:

different stimuli (light, weight, tone) has different percentages until you can sense a difference in change