Visual Processes and Object Recognition Slides

Question 1

trichromat

Answer 1

someone with normal vision

Question 2

two kinds of hereditary color deficiency

Answer 2

• red or green cone peak sensitivity shifted

- red or green cones absent

Question 3

visual acuity

Answer 3

how accurately light is focused on retina

Question 4

area v1

Answer 4

primary visual cortex

striate cortex

Question 5

v1 cells code…

Answer 5

lines, orientation, and direction

Question 6

simple cells

Answer 6

respond to elongated bars or edges
orientation selective
monocular or binocular
separate on or off
length summation

Question 7

complex cells

Answer 7

orientation selective
homogenous receptive field
almost all binocular
length summation

Question 8

blindsight

Answer 8

cortical blindness from damage to v1 results in hemianopias and scotomas

Question 9

hemianopias

Answer 9

loss of half of visual field

Question 10

scotomas

Answer 10

loss of small portion of visual field

Question 11

pathways to higher visual areas can…

Answer 11

bypass V1

Question 12

corticol blindness from damage to V1 causes…

Answer 12

hemianopias and scotomas

Question 13

extrastriate cortex is composed of

Answer 13

areas v2 and v3

Question 14

area v4

Answer 14

receives input from v2 and v3
primary source of input to ventral stream
perception of fine detail and color perception

Question 15

damage to v4 can cause

Answer 15

acromatopsia

Question 16

congential achromatopsia

Answer 16

no cone cell activity at all

black and white vision

Question 17

extrastriate

Answer 17

v5

Question 18

v5

Answer 18

MT region
speed and direction of motion
structure from motion
guidance of eye movements to moving targets

Question 19

akinetopsia

Answer 19

caused by MT damage

deficit in motion perception

Question 20

multimodal perception

Answer 20

areas that combine signals from multiple sources
Superior colliculus
superior temporal sulcus

Question 21

synesthesia

Answer 21

mixing of sensations

Question 22

two types of synesthesia

Answer 22

projectors

associators

Question 23

projectors

Answer 23

experience the color in the outside world

Question 24

associators

Answer 24

experience the change internally

Question 25

structure of synesthesia

Answer 25

increased connectivity in visual areas (more for projectors)

Question 26

in fMRI synthesthetes present with…

Answer 26

greater activity in primary cortex

Question 27

structure where a large difference is shown between synthesthete and control

Answer 27

v4

Question 28

illusions

Answer 28

v1 generally silent to visual illusions

higher visual areas respond to illusions in ventral stream

Question 29

perceptual reorganization

Answer 29

cortical plasticity

ex: blind recruit visual cortex for tactile discrimination

Question 30

region associated with ventral stream

Answer 30

occipitotemporal cortex

Question 31

region associated with dorsal stream

Answer 31

posterior parietal cortex