4. SENSATION & PERCEPTION

Question 1

Define: sensation

Answer 1

stimulation of sense organs by absorption of energy (ie. light, sound, etc.)

Question 2

Define: perception

Answer 2

selection, organization, interpretation of sensory input

Question 3

How are sensation and perception related

Answer 3

perceptions deals with how somebody interprets the sensations they have experienced

Question 4

Define: amplitude (light)

Answer 4

height of the light waves, affects perception of brightness

Question 5

Define: wavelength (light)

Answer 5

distance between peaks, affects perception of color

Question 6

Define: purity (light)

Answer 6

how varied the mix of different wavelengths of light is

Question 7

Define: saturation (vision)

Answer 7

richness of colors, refers to the relative amount of whiteness in a color

Question 8

As whiteness declines, saturation ___

Answer 8

increases

Question 9

Function: cornea

Answer 9

acts as a transparent “window” that lets light into the eye, works with the lens to form an upside down image of objects on the retina and adjust focus of the image

Question 10

Function: lens

Answer 10

a transparent film that focuses the light rays falling on the retina

Question 11

Define: accomodation

Answer 11

curvature of the lens adjusts to alter visual focus

Question 12

When you focus on a close object, the lens of your eye accommodates to become ____ to give you a clear image.

Answer 12

thicker

Question 13

When you focus on a distant object, the lens of your eye accommodates to become ____ to give you a clear image.

Answer 13

flatter

Question 14

Define: pupil

Answer 14

opening in the center of the iris that helps regulate the amount of light coming in

Question 15

List two things the pupil does in response to bad lighting.

Answer 15

Pupil dilates, image loses sharpness

Question 16

List two things the pupil does in response to bright lighting.

Answer 16

Pupil constricts, image becomes/stays sharp

Question 17

Function: retina

Answer 17

light absorption, image processing, transmits visual info to the brain

Question 18

Define: fovea

Answer 18

a tiny spot in the center of the retina that only contains cones (point where visual acuity is the greatest)

Question 19

Define: iris

Answer 19

colored ring of muscle surrounding pupil

Question 20

Define: optic nerve

Answer 20

nerve situated in the retina that transmits visual information to the brain

Question 21

What is another name for the optic disk

Answer 21

blind spot

Question 22

Define: trichromatic theory

Answer 22

the human eye has three types of receptors (R, G, B) with differing sensitives to different light wavelengths and our eyes mix the three colors together to make all those that we can see

Question 23

Define: rods

Answer 23

“black and white” visual receptors

Question 24

Define: cones

Answer 24

visual receptors that are able to detect color, high visual acuity, found mainly in the center of the retina

Question 25

Primary flow of info from retina to brain

Answer 25

optic nerve -> optic chiasm -> thalamus (lateral geniculate nucleus) -> occipital lobe (primary visual cortex) -> feature detectors process input -> dorsal stream (where the object is)/ventral stream (what an object is)

Question 26

Define: sensory adaptation

Answer 26

when individuals adapt to repetitive senses over time

Question 27

List three examples of sensory adaptations

Answer 27

1. Sound of loud music appears to have become quieter over a long period of exposure
2. Smell of a restaurant seems to fade as you are eating
3. Feeling of jewelry is no longer noticed

Question 28

Define: feature detectors

Answer 28

neurons that respond selectively to very specific features of more complex stimuli

Question 29

At what level does the visual cortex process information

Answer 29

highly specialized (ex. a single neuron may only be able to process one type of line)

Question 30

Problem with trichromatic theory of color vision

Answer 30

Does not explain complementary afterimages (after looking at a bright object for a long time and looking away, you will see an “afterimage” in complementary colors, ie. the sun)

Question 31

Define: opponent process theory

Answer 31

color perception depends on receptors that make antagonistic responses to three pairs of colors (red/green, yellow/blue, black/white)

Question 32

Evidence for trichromatic theory

Answer 32

color blindness, ability to make all colors from basic R,G,B

Question 33

Evidence against trichromatic theory

Answer 33

complementary afterimages

Question 34

Evidence for opponent process theory

Answer 34

complementary afterimages, color blindness (dichromats)