WEEK 4 + 5 - VISUAL PERCEPTION AND DISORDERS

Question 1

order of anatomy of visual pathway

Answer 1

retina, optic nerve, optic chiasm, optic tract, lateral geniculate nucleus (LGN), optic radiation, primary visual cortex (V1)

Question 2

if ONE eye is damaged

Answer 2

unilateral field loss

Question 3

if the OUTER corners of eyes are damaged

Answer 3

bitemporal hemianopsia

Question 4

if ONE inner and ONE outer eye is damaged

Answer 4

homonymous hemianopsia

Question 5

V1 upper visual field

Answer 5

ventral V1 and LGN

Question 6

lower visual field

Answer 6

dorsal V1 and LGN

Question 7

fovea

Answer 7

posterior V1

Question 8

periphery

Answer 8

anterior V1

Question 9

left visual field

Answer 9

right LGN

Question 10

right visual field

Answer 10

left LGN

Question 11

Two visual stream hypothesis (TVSH)

Answer 11

model that proposes proposes two distinct neural pathways in the brain that process visual information

Question 12

dorsal stream

Answer 12

vision to direct ACTIONS

Question 13

ventral stream

Answer 13

vision to PERCEIVE environment

Question 14

visual agnosia

Answer 14

impairments in deriving meaning to visually presented, despite intact sensory and low-level vision, and normal language and semantic function

Question 15

apperceptive visual agnosia

Answer 15

failure to process visual elements together for perception (ie. unable to identify, copy or match drawings to what they see)

Question 16

associative visual agnosia

Answer 16

perception is stripped of meaning (CANNOT visually identify what they are seeing)

Question 17

simultanagnosia

Answer 17

Inability to appreciate the overall meaning from complex picture or scene (ie. Cookie Theft Task)

Question 18

hemi-attention

Answer 18

one modality affected, most commonly vision

Question 19

hemi-neglect

Answer 19

more than one sensory modality is affected

Question 20

prosopagnosia

Answer 20

visual impairment in recognising faces

Question 21

topographical agnosia

Answer 21

visual impairment for recognising landmarks

Question 22

visual form agnosia

Answer 22

visual impairment for recognising shape/form

Question 23

Visual Object and Space Perception Battery (VOSP)

Answer 23

an initial screening test (shape detection), to assess whether the visual and sensorial capacity of patients are sufficient to complete the other subtests

Question 24

Patient DF

Answer 24

developed visual agnosia after being poisoned - formed basis of TVSH model

Question 25

optic ataxia

Answer 25

inability to use vision for the control of actions

Question 26

Patient RV

Answer 26

had parietal lobe damage in two hemispheres as result of two strokes

Question 27

Implications for vision

Answer 27

People need to recognise objects first and then decide which is appropriate for a particular content

Question 28

Implications for vision

Answer 28

Pathways CAN function independently - but usually interact to produce goal-directed behaviour together

Question 29

double dissociation support for TVSH

Answer 29

the conclusions of doing a double dissociation shows ventral stream = visual perception; dorsal stream = visual control of actions