Ch 6: What is visual perception

Question 1

lower-order visual information

Answer 1

perception of color

Question 2

higher-order visual information

Answer 2

recognising objects

Question 3

Cones

Answer 3

Color perception
short wavelength –> blue
medium –> green
long –> red

Question 4

Rods

Answer 4

perception in the dark

more sensitive to light information

Question 5

Magnocellular cells (M cells)

Answer 5

pass on motion related information

Question 6

Parvocellular cells (P cells)

Answer 6

small receptive fields and mainly pass on information relating to color perception

Question 7

What- route

Answer 7

occipital-temporal (ventral)
info from parvocellular system
recognition of objects and processing of color, shape and texture

Question 8

Where-route

Answer 8

occipital-parietal (dorsal)
input from the magnocellular system
visuospatial processing, location of objects in space, guiding of visually controlled movements to these objects

Question 9

apperceptive agnosia

Answer 9

the percept cannot be formed

Question 10

associative agnosia

Answer 10

the formed percept cannot be associated with semantic knowledge

Question 11

Visual acuity

Answer 11

measure of the smallest details a person can distinguish

Question 12

Achromatopsia

Answer 12

only seeing pale or grey tones

Question 13

Prosopagnosia

Answer 13

problems with face recognition and identification

Question 14

akinetopsia

Answer 14

movement blindness

Question 15

visual form agnosia

Answer 15

patient cannot recognise, match, copy or discriminate simple visual stimuli

Question 16

ventral stimulation agnosia (integrative agnosia)

Answer 16

patient cannot merge the independent detached parts into one percept

Question 17

color agnosia

Answer 17

not being able to categorise, name or recognise colours

Question 18

brightness agnosia

Answer 18

the inability to recognise brightness

someone cannot see if light are on or off

Question 19

object agnosia

Answer 19

patients cannot name objects and are even unable to organise objects from the same category on the basis of semantic knowledge

Question 20

Blindsight

Answer 20

some people with loss of the visual field can still perceive visual stimuli in the blind field (unconscious)

demonstrated with the forced-choice paradigms

Question 21

Visual illusion

Answer 21

distortion of the actual external stimulus

Question 22

visual hallucination

Answer 22

no external stimulus present but you see something

Question 23

Charles Bonnet Syndrome (CBS)

Answer 23

caused by an impaired transmission of visual information to the visual cortex –> patient sees thing that aren’t there.

Question 24

Anton’s syndrome (anosognosia)

Answer 24

some patients that are cortically blind due to bilateral infarctions in the V1 deny their blindness and confabulate a very detailed visual world