CHAPTER 4

Question 1

Define sensation

Answer 1

how the senses detect visual, auditory and other sensory stimuli and encode them as neural signals

Question 2

define Perception

Answer 2

how sensory information is selected, organized and interpreted

Question 3

What are the 2 types of perception?

Answer 3

1) Bottom-up processing

2) top-down processing

Question 4

Describe Botton-up processing

Answer 4

constructing an image from its parts. Ex: perceiving an object on the basis of its edges

Question 5

describe top-down processing

Answer 5

constructing perceptions based on our experience and expectations

Question 6

What is the McGurk effect?

Answer 6

The illusion occurs when the auditory component of one sound is paired with the visual component of another sound, leading to the perception of a third sound

Question 7

define absolute threshold

Answer 7

minimum of a stimulus needed for the nervous system to detect a change 50% of the time.

Question 8

Define Eagleman’s experiment

Answer 8

Time delay when making a decision based on previous attempts. Basically, we compare out current choices with previous ones so is there really a difference? basically he explored the idea of free will

Question 9

define inattention blindness. state the example the textbook used

Answer 9

Failure to detect stimuli that are in plain sight when our attention is focused elsewhere.

Ex: individuals were asked to count how many times 2 people in the white shirts were tossing the football around. well at the end of the experiment when they were told to report the number they were also told that in the video there was a man with a gorilla suit facing around. More than 50% of people failed to see the gorilla because they were so focused on counting the number of times the football was thrown.

Question 10

define change blindness and where is it mostly found?

Answer 10

failure to detect obvious changes in one’s environment

Mostly found in pilots

Question 11

define subliminal perception

Answer 11

below absolute threshold for conscious awareness

Question 12

define accommodation

Answer 12

Changing the shape of the lens to focus on objects near or far

Question 13

define presbyopia

Answer 13

loss of lens flexibility

Question 14

define colour blindness

Answer 14

decrease in number of cones in the eye

Question 15

define visual agnosia

Answer 15

deficit in perceiving objects. A person with this condition can tell the shape and colour BUT not recognize/name the object

Question 16

Are there more rods or cones?

Answer 16

rods

Question 17

Which ones help you see during daytime and nightime

Answer 17

daytime -> cones

night time -> rods

Question 18

which area of the eye has no rods?

Answer 18

fovea

Question 19

What photopigment is located in rods?

Answer 19

rhodopsin

Question 20

Trichromatic theory

Answer 20

Idea that colour vision is based on our sensitivity to 3 primary colours. —> red, green, blue

Question 21

Opponent-process theory, name an example

Answer 21

Theory that we perceive colour in terms of 3 pairs of opponent colours: either red & green, blue & yellow, or black & white.

Example in textbook used was the Canadian flag experiment

Question 22

Nearsightness vs farsightedness

Answer 22

Nearsightness –> light focused in the front

farsightedness –> light focused in the back

Question 23

define feature detectors

Answer 23

each detector is tuned to a particular aspect of the stimulus information

Question 24

define the Gestalt principles

Answer 24

our perceptual world is organized in ways that the stimulus is not. the the organization must be contributed by the perceiver. Example: kanizsa squares

” your perception goes beyond the info given”

Question 25

explain perception and the visual cortex

Answer 25

visual inför from the retina travels to the superior colliculus as well as the lateral geniculate nucleus (LGN) and then to the secondary cortex(V2) and then along 2 visual pathways.

1) “where” pathway, going to the partial lobe, which processes visual form, position, and motion
2) “ what” pathway, to the temporal lobe which processes visual form and colour

Question 26

define interposition

Answer 26

Object partly blocks your view of another. You perceive the partially blocked object as farther away.

Question 27

define linear perspective

Answer 27

Parallel lines known to be the same distance apart

appear to grow closer together, or converge as they recede into the distance.

Question 28

define relative size

Answer 28

Larger objects are perceived as being closer to the viewer, and smaller objects as being farther away.

Question 29

define texture gradient

Answer 29

the texture of objects become less apparent as objects move further away

Question 30

Müller-Lyer Illusion

Answer 30

A line of identical length appears longer when it ends in a set of arrowheads pointing inward than in a set of arrowheads pointing outward.

A)
B) >-<

B appears longer but they’re the same size

Question 31

which people are not susceptible to the muller-layer illusion?

Answer 31

the Zulu people

Question 32

Define ponzo illusion

Answer 32

objects closer to the converging line as larger than those far away when they’re all the same size.

Example: Train tracks. the closest rail looks larger than the ones far away

Question 33

define carpentered world

Answer 33

describes how those who live in cities are exposed to a higher percentage of straight lines, right angles and square corners

Question 34

define Akinetopsia aka Motion blindness

Answer 34

difficulty of perceiving objects in motion

Question 35

Which part of the brain is affected by motion blindness?

Answer 35

occipital lobe (damage to this causes motion blindness)

Question 36

define blinding problem

Answer 36

we don’t really know how - our brains manage to combine or “bind” these pieces of information of the real world into a unified whole(colour, depth, movement, form etc)

Question 37

cornea

Answer 37

bends lights and protect ye

Question 38

iris

Answer 38

how much light enters

Question 39

lens

Answer 39

focus and accommodation

Question 40

retina

Answer 40

light sensitive surface

Question 41

pupil

Answer 41

dilation, excitement

Question 42

rods

Answer 42

respond to low light

Question 43

cones

Answer 43

respond to high light, colour

Question 44

fovea

Answer 44

highest concentration of cones

Question 45

blind spot

Answer 45

no rods or sense receptors