module 22 and 23 quiz Flashcards
what is a lights wavelength?
the distance from one peak to the next
a wavelength determines hue, what is hue?
hue is the color we experience
a light waves amplitude, or height, determines its intensity, what is intensity?
intensity is the amount of energy the wave contains, intensity influences brightness
short wavelength=
high frequency, bluish colors
long wavelength=
low frequency, reddish colors
great amplitude (taller)=
bright colors
small amplitude (shorter)=
dull colors
light enters the eye through the _____, which bends light to help provide focus
cornea
after the cornea, light then passes through the ______, a small adjustable opening
pupil
surrounding the pupil and control its size is the _____, a colored muscle that dialates or constricts in response to light
iris
after passing thru the pupil, light hits the transparent _____ in your eye, that changes shape to help focus images on the retina
lens
the light-sensitive inner surface of the eye, contains rods and cones, and layers of nerurons that begin sensory information
retina
the process by which the eyes lens changes shape to focus near or far objects on the retina
accommodation
retinal receptors that detect black, white, and gray, and are sensative to movement. necesary for peripheral and twilight vision when cones don’t respond, 120 million
rods
retinal receptors that are located near the center of the retina and function in daylight or well-lit conditions. detect fine detail and color perceptions, 6 million
cones
a chemial reaction sparks nearby bipolar cells, then bipolar cells activate ganglion cells, those axons twine together to form the ______, which is the nerve that carries nerual impulses from the eye to the brain
optic nerve
an area with no receptor cells, where the optic nerve leaves the eye
blind spot
cones cluster in and around the _____, the retinas area of central focus
fovea
technically a tomato is everything but red because it _______ the long wavelenghts of red
reflects/rejects
Three color theory:
the retina contains three different types of color receptors, one most sensitive to red, blue, or green, which when stimulated in combination can produce a perception of any color
opponent-process theory:
the theory that opposing retinal processes (red-green, blue-yellow, white-black) enable color vision. some cells are stimulated by green and inhibited by red. the reason you cant see greenish red. also the cause of afterimages
color perception occurs in two stages:
the retinas red, green, and blue cones respond to different degrees so stimuli, like 3 color theory suggests, then the cones responses are processed by opponent processing cells (opponent process theory)
feature detectors:
nerve cells in the occipital lobes visual cortex that respond to a scenes edges, lines, angles, and movement
parallel processing:
processing many aspects (motion, form, depth, color) of a problem simultaneusly; the brains natural mode of information processing for many functions, including vision. the reason we can recognize a face
gestalt:
an organized whole; our tendency to integrate peices of information into an organized whole.
figure-ground:
perceivng any object as distinict from its surroundings. the organization of the visual field into objects (the figures) that stand out from their surroundings (ground)
our mind brings order and form to other stimuli by following certain rules for _____
grouping; the perceptual tendency to organize stimuli into coherent groups
Proximity:
grouping; we group nearby figures together. we see not six separate lines, but three sets of two lines
continuity:
grouping; we percive smooth continuous patterns rather than discontinuous ones. instead of seeing a series of alternating semicircles we see it as two continuous lines, one straight one curvy
Closure:
grouping; we fill in gaps to create a complete, whole object. we can see a triangle from 3 semi circles because our brain constructs the triangle
depth perception:
allows us to judge distance; the ability to see objects in three dimensions although the images that strike the retina are two dimensional
binocular cue:
the depth cue, such as retinal disparity, that depends on the use of two eyes. people that see with two eyes percive depth thanks to binocular cues
we use bionoular cues to judge the distance of nearby objects, one such cue is _______, the inward angle of the eyes focusing on a nearby objcet
convergence
retinal disparity:
since your eyes are 2.5 inches apart, your retinas receive slightly different images of the world. by comparing these two images, your brain can judge how close an object is to you. the greater the disparity (difference) between the two objects, the closer the object
monocular cues:
depth cues avalible to each eye seperately, like interpositon or linear persepctive
Phi phenomenon
all illusion of movement created when two or more adjacent lights blind on and off in quick succession. blinking lights that create what looks like a moving arrow
relative height:
we perceive objects higher in our visual field as farther away
relative size:
if we assume two objects are similar in size, people perceive the one that casts as smaller retinal image as farther away
interpositon:
if one object paritally blocks our view of another we perceive it as closer
relative motion:
as we move, objects that are actually stable appear to be moving. objects in front of the point will appear to move backward, the farther an object is the faster it will seem to move
linear persepctive:
parallel lines appear to meet in the distance, the sharper angle of convergence, the greater the percieved distance
light and shadow:
shading produces a sense of depth consistent with our assumption. light comes from above
perceptual constancy:
being able to recognize objects without being deceived by changes in their color, brightness, shape, or size even as illumination and retinal images change, a top down process.
color constancy:
perceiving objects has having a consistant color, even if changing illumination alters the wavelenghts reflected by the object
relative luminance (brightness constancy depends on this):
the amount of light an object reflects relative to its surroundings, white paper reflects 90% of light falling on it while black paper reflects 10%
size constancy:
we perceive on object as having an unchanging size even while our distance from it varies
critical period:
an optimal period when exposure to certain stimuli or expirences is required. when critial period is passed, for example, putting an eye patch on for a long amount of time will do nothing to your sight
perceptual adaptation:
the ability to adjust to changed sensory input, including an artificailly displaced or even inverted visual feild
