chapter 6

Question 1

four major concepts in object recognition

Answer 1

1. use terms precisely
2. object perception in unified
3. perceptual capabilities are flexible and robust
4. the product of perception is interwoven with memory

Question 2

object constancy

Answer 2

our ability to recognize an object in countless situations

Question 3

what are the three factors that causes variability in how we see an object?

Answer 3

1. viewing position (what angle you see it)
2. illuminating conditions (lighting)
3. context (why you are seeing it)

Question 4

Ames Room Illusion

Answer 4

visual illusion that makes you think one person is much larger than the other when it is truly just the distance between the two
- showed how the perceptual system automatically uses many sensory cues and past knowledge to maintain object constancy

Question 5

computational problems in object recognition

Answer 5

• object recognition must accommodate sources of variability
• system must recognize that changes in perceived shape may reflect actual changes in the object
• object recognition must be general enough to support object constancy and specific enough to distinguish slight differences

Question 6

fasciculi

Answer 6

two major fiber bundles that contain output from V1, involved in object recognition

Question 7

ventral stream

Answer 7

• occipitotemporal stream
• what stream
• inferior

Question 8

dorsal stream

Answer 8

• occipitoparietal stream
• where pathway
• posterior/superior

Question 9

if you have damage to your parietal lobe, which stream is damaged and how does that affect you?

Answer 9

Dorsal stream; damaged spatial perception, or cannot tell where an object is

Question 10

Cat experiment for what and where pathways

Answer 10

• cats performed two tasks: locate a sound and distinguish between two different sounds

Question 11

what did the cat experiment show?

Answer 11

• inhibit anterior auditory (ventral stream) region caused deficits in the pattern discrimination task but not in the localization task
• inhibited posterior auditory region (dorsal stream) caused deficit in the localization task but not in the pattern discrimination task

Question 12

What are the symptoms of a patient with damage to the ventral stream

Answer 12

cannot name objects, recognize faces, or distinguish a rectangle from a square
- but can use vision to guide actions

Question 13

What are the symptoms of a patient with damage to the dorsal stream

Answer 13

-cant integrate their vision with their movements
- cannot accurately reach out to grasp an object
- while walking they can describe what they see, but they bump into objects, oblivious to their location

Question 14

agnosia

Answer 14

inability to process sensory information even though the sense organs and memory are not defective

Question 15

visual agnosia

Answer 15

-difficulty recognizing objects that are presented visually
- recognition using touch/hearing are usually fine

Question 16

3 types of visual agnosia

Answer 16

apperceptive
integrative
associative

Question 17

apperceptive agnosia

Answer 17

difficulty recognizing objects or perceive their correct form

Question 18

what tests are used for apperceptive visual agnosia?

Answer 18

unusual views object test, the shadows test

Question 19

integrative visual agnosia

Answer 19

perceive parts of an object but are unable to integrate them as a whole
- ie can see corners and curves of shapes, but cannot tell that it is two squares and a circle

Question 20

associative visual agnosia

Answer 20

inability to link a percept with its semantic info, such as its names, properties, and function
- can perceive objects, but cannot understand them
- they can copy an image down easily, but cannot say what they just drew

Question 21

tests for associative visual agnosia

Answer 21

matching by function test
- participants are shown three pictures and are asked to point to the two that are functionally similar

Question 22

prosopagnosia

Answer 22

inability to recognize faces
-damage is in ventral pathway and the FFA
- many cases lesions are bilateral

Question 23

two types of prosopagnosia

Answer 23

• acquired (abrupt loss due to an accident) and congenital CP (lifetime impairment from birth)

Question 24

monozygotic vs dizygotic twins in facial recognition

Answer 24

monozygotic twins are more similar in ability to recognize faces than dizygotic

Question 25

ASD and face recognition

Answer 25

ASD is linked to abnormal face recognition due to the hypoactivity (less) in the FFA

Question 26

how could CP arise?

Answer 26

from impaired info transmission between FFA and other face processing regions

Question 27

what supports the hypothesis that the brain has functionally different systems for face and object recognition

Answer 27

double dissociations
- prosopagnosia vs patient C.K

Question 28

holistic processing

Answer 28

How we accomplish holistic processing
- we recognize an individual but the sum of their parts
- people with prosopagnosia are unable to form a holistic representation necessary for face perception

Question 29

prosopagnosia experiment

Answer 29

• participants were asked to recognize line drawings of faces and houses
• they were better at identifying an individual facial feature of a person when that feature was showed next to other parts of tjhat persons face

Question 30

Thatcher Illusion

Answer 30

You are unable to recognize when certain features are wrong when a picture is upside down