Chapter 4 - sense of vision

Question 1

What’s the scientific word for light?

Answer 1

electromagnetic radiation!

Question 2

Do wavelength and frequency mean the same thing?

Answer 2

Yes!

light = wavelength 
sound = frequency

Question 3

What does the amplitude of light signify?

Answer 3

the brightness of a color.

Question 4

What does the wavelength of light signify?

Answer 4

the color.

Question 5

What is visual acuity?

Answer 5

detailed vision!

Question 6

define cornea:

Answer 6

provides protection from damage.

Question 7

define pupil:

Answer 7

dark opening in the eye through which light passes.

Question 8

define iris:

Answer 8

colored part which changes the size of the pupil to let in more or less light.

Question 9

define lens:

Answer 9

focuses light onto back of eye.

Question 10

define retina:

Answer 10

sheet of tissue at back of the eye containing visual processing cells that convert light to neural impulses.

Question 11

What is accommodation?

Answer 11

automatic adjustment of the lens of the eye for seeing at different distances.

Question 12

What are the two types of retinal neurons?

Answer 12

cones & rods!

Question 13

define cones and rods:

Answer 13

rods: perceives light and dark.
cones: perceives color and detail.

Question 14

What is dark adaptation?

Answer 14

exposure to darkness causes eyes to become more sensitive, allows for better vision in the dark.

Question 15

What is the trichromatic theory?

Answer 15

theory that color vision arises from the combinations of neural impulses from three different kinds of sensors (cones).

Question 16

CONES:

red (long), green (_____), blue (_____)?

Answer 16

red(long), green(medium), blue(short).

Question 17

What is color deficiency?

Answer 17

when you are born without one or more types of cones.

Question 18

What is the color opponent system?

Answer 18

if a color is present, it causes cells that register it to inhibit the perception of the complementary color.

Question 19

What is afterimages?

Answer 19

images left behind by a previous perception.

Question 20

What are the 3 opposing pairs?

Answer 20

red & green.
blue & yellow.
black & white.

Question 21

What are feature detectors?

Answer 21

cells that respond to only one specific visual stimulus

ex. angles, horizontal lines, close objects, far objects.

Question 22

What is perceptual constancy?

Answer 22

perception of characteristics that occurs when an object or quality, looks the same even though the sensory information striking the eyes changes.

ex. size, shape, or color.
info. ^^^^ not born with these 3.

Question 23

What is depth perception?

Answer 23

ability to use the two-dimensional image projected on the retina to perceive three dimensions.

Question 24

How many types of visual cues are there for depth perception?

Answer 24

three types!
A: Monocular cues
A: Binocular cues
A: Pictorial depth cues?

Question 25

monocular cues:

Answer 25

for distance can be picked up with one eye.

Question 26

binocular cues:

Answer 26

cues to distance that arise from both eyes working together. (20ft or less).

info. closer image, greater disparity (difference) between both images.

Question 27

binocular disparity:

Answer 27

has to do with each individual image.

Question 28

convergence:

Answer 28

has to do with position of eyes and angle of their focus.

Question 29

pictorial depth cues:

Answer 29

drawing depth perception into artwork.

Question 30

motion parallax:

Answer 30

having images of objects at different distances moving across the retina at different rates.

ex. in a car, close stuff fly by, far things go slowly.

Question 31

accommodation:

Answer 31

covered earlier in lecture.

Question 32

What’s the difference between change blindness and inattentional blindness?

Answer 32

change blindness: when people fail to detect changes to visual details of a scene.

inattentional blindess: failure to perceive objects that aren’t the focus of attention.