Sensation and Perception - 1

Question 1

Weber’s law

Answer 1

the “just noticeable difference” or “difference threshold” is a constant proportion of the original stimulus size

Question 2

signal detection theory

Answer 2

detection depends on experience, expectations, alertness, etc.
(more likely to notice a door slam outside when waiting on the pizza guy)

Question 3

sensory adaptation

Answer 3

diminished sensitivity as a result of constant stimulation (“can you feel your underwear”)

Question 4

sensory habituation

Answer 4

diminished sensitivity due to regular exposure (do you notice the train?)

Question 5

perceptual set

Answer 5

tendency to see something as part of a group – speeds up signal processing

Question 6

inattentional blindness

Answer 6

failure to notice something added because you’re so focused on another task (gorilla video)

Question 7

change blindness

Answer 7

failure to notice a change in the scene (door study – people did not notice when the person they were talking to was replaced with another person)

Question 8

cocktail party effect

Answer 8

notice your name across the room when its spoken, when you weren’t previously paying attention

Question 9

cornea

Answer 9

protects the eye

Question 10

pupil/iris

Answer 10

controls the amount of light entering the eye

Question 11

lens

Answer 11

focuses light on the retina

Question 12

retina

Answer 12

contains rods and cones

Question 13

fovea

Answer 13

area of best vision (cones here)

Question 14

rods

Answer 14

black/white, dim light

Question 15

cones

Answer 15

color, bright light (red, green, blue)

Question 16

bipolar cells

Answer 16

connects rods/cones and ganglion cells

Question 17

ganglion cells

Answer 17

opponent-processing occurs here

(the human visual system interprets information about color by processing signals from photoreceptor cells in an antagonistic manner)

Question 18

blind spot

Answer 18

occurs where the optic nerve leaves the eye

Question 19

feature detectors

Answer 19

specialized cells that see motion, shapes, lines, etc.
located in occipital lobe (experiments by Hubel & Wiesel)

Question 20

trichromatic

Answer 20

three cones for receiving color (blue, red, green)
explains color blindness – they are missing a cone

Question 21

opponent process

Answer 21

complementary colors are processed in the ganglion cells – explains why we see an after image

Question 22

negative afterimage

Answer 22

when you can no longer see the stimulus, you see its complementary color (seeing green after seeing a red apple)

Question 23

positive afterimage

Answer 23

when you can no longer see the stimulus, you see the color that it really is (seeing red after seeing a red apple)

Question 24

visual capture

Answer 24

visual system overwhelms all others (nauseous in an IMAX theater – vision trumps vestibular system)

Question 25

constancies

Answer 25

recognize that objects do not physically change despite changes in sensory input (size, shape, brightness)

Question 26

Phi Phenomenon

Answer 26

adjacent lights blink on/off in succession – looks like movement (traffic signs with arrows)

Question 27

stroboscopic movement

Answer 27

motion produced by a rapid succession of lightly varying images (animations)

Question 28

monocular clues

Answer 28

how we form a 3D image from a 2D image

Question 29

interposition

Answer 29

overlapping images appear closer

(monocular clue)

Question 30

relative size

Answer 30

2 objects that are usually similar in size, the smaller one is further away

(monocular clue)

Question 31

relative clarity

Answer 31

hazy objects appear further away

(monocular clue)

Question 32

texture gradient

Answer 32

coarser objects appear further away

(monocular clue)

Question 33

relative height

Answer 33

things higher in our field of vision look further away

(monocular clue)

Question 34

linear perspective

Answer 34

parallel lines converge with distance (think railroad tracks)

(monocular clue)

Question 35

motion parallax

Answer 35

closer objects appear to move faster than objects that are farther

(monocular clue)

Question 36

binocular clues

Answer 36

how both eyes make up a 3D image

Question 37

retinal desparity

Answer 37

image is cast slightly different on each retina, location of image helps us determine depth

(binocular clue)

Question 38

convergence

Answer 38

eyes strain more (looking inward) as objects draw nearer

(binocular clue)

Question 39

top-down processing

Answer 39

using our prior experience, knowledge, and expectations to interpret sensory information

Question 40

bottom-up processing

Answer 40

sensory data is interpreted based without reliance on prior knowledge or concepts