Sensation And Perception

Front 1

electromagnetic radiation

Back 1

a physical phenomena that is simultaneously both a wave and a stream of particles

Front 2

wavelength

Back 2

the distance b/w 2 successive peaks of a wave

Front 3

electromagnetic spectrum

Back 3

the entire range of wavelengths of electromagnetic radiation

Front 4

photons

Back 4

single particles of light

Front 5

optic array

Back 5

spatial pattern of light rays; vary in brightness and color; enter eyes from different location in a scene

Front 6

field of view

Back 6

the portion of the surrounding space you can see when you eyes are in a given position

Front 7

acuity

Back 7

measure of how clearly fine detail is seen

Front 8

extraocular muscles

Back 8

3 pairs of muscles around each eye that enable us to move our eyes while in the same direction

Front 9

optic axis

Back 9

an imaginary diameter line from the front to the back of the eye, passing through center of lens

Front 10

sclera

Back 10

outer membrane of eye; protective covering; visible portion is white of the eye

Front 11

choroid

Back 11

middle membrane of eye; lining interior of sclera; contains most of blood vessels that supply inside of eye with oxygen and nutrients

Front 12

retina

Back 12

inner membrane of eye; made up of neurons including photoreceptors that convert light entering eye into neural signals

Front 13

cornea

Back 13

a transparent membrane at the front of the eye; light enters the eye by first passing through cornea; which sharply refracts light

Front 14

iris

Back 14

the colored part of the eye; a small circular muscle with an opening in the middle (pupil) through which light enter the eye

Front 15

pupil

Back 15

opening in the middle of iris, through which light enters

Front 16

pupillary reflex

Back 16

automatic process by which iris contracts and relaxes to control the size of the pupil , in response to the brightness of light entering

Front 17

anterior chamber

Back 17

space b/w cornea and the iris; filled with aqueous humor

Front 18

posterior chamber

Back 18

space b/w the iris and lens; filled with aqueous humor

Front 19

aqueous humor

Back 19

clear, thin fluid filling the anterior and posterior chambers of the eye

Front 20

vitreous chamber

Back 20

the main anterior portion of the eye; filled with vitreous humor

Front 21

vitreous humor

Back 21

clear, somewhat gel-like fluid filling the vitreous chamber of the eye

Front 22

intraocular pressure

Back 22

pressure of the fluids in the 3 chambers of the eye

Front 23

lens

Back 23

transparent structure near front of eye; refracts light passing through pupil so it focuses properly in retina

Front 24

focal length

Back 24

distance from lens at which the image of an object is in focus when the object is far away from the lens

Front 25

diopters

Back 25

units used to express the power of a lens

Front 26

zonule fibers

Back 26

fibers that connect the lens to the choroid; they pull on lens to change shape

Front 27

ciliary muscles

Back 27

tiny muscles attached to choroid; relax and contract to control zonule fibers which change the shape of lens

Front 28

retinal image

Back 28

clear image on retina of optic tract

Front 29

nuclear layers

Back 29

3 main layers of the retina: outer nuclear layer, inner nuclear layer, and ganglion cell layer

Front 30

synaptic layers

Back 30

in the retina; 2 layers separating the 3 nuclear layers

Front 31

photoreceptors

Back 31

retinal neurons (rod/cones) transduce light into neural signals

Front 32

rods

Back 32

provide b&w vision in dim-light

Front 33

cones

Back 33

provide high-acuity color vision in bright light

Front 34

pigment epithelium

Back 34

dark layer behind photoreceptors

Front 35

optic disk

Back 35

blind spot; no photoreceptors; where the retinal ganglion cells exit the eye

Front 36

fovea

Back 36

region in center of retina where light strikes the retina; no rods - high density of cones

Front 37

photopigment

Back 37

a molecule with the ability to absorb light and initiate transduction

Front 38

dark adaption

Back 38

process of adjusting retinal sensitivity as a person moves from a bright environment to a darker one

Front 39

convergence

Back 39

a property of retinal circuits in which multiple photoreceptors send signals to one RGC

Front 40

preferred stimulus

Back 40

the type of stimulus that produces a neurons maximum firing rate

Front 41

lateral inhibition

Back 41

inhibitory neural signals transmitted by horizontal cells in retina circuit

Front 42

edge enhancement

Back 42

process by which the visual system makes edges as visible as possible; facilitating perception of where one object ends and one begins

Front 43

strabismus

Back 43

disorder of the extraocular muscles in which 2 eyes are not aligned; lazy eye

Front 44

amblyopia

Back 44

condition where fine vision doesn't develop in one eye

Front 45

near point

Back 45

the closest distance at which a person can bring an object into focus

Front 46

cataract

Back 46

progressive clouding of the lens; if left alone can cause blindness

Front 47

glaucoma

Back 47

a condition in which intraocular pressure is too high for the person eye ; usually caused by blockage of openings that let aqueous humor drain from the anterior humor

Front 48

floaters

Back 48

shadows in the retina thrown by debris within the vitreous humor

Front 49

phosphenes

Back 49

brief tiny bright flashes int he person's field of view not caused by light

Front 50

macular degeneration

Back 50

a condition characterized by damage to the photoreceptors in a region at the center of the retina